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Tumor Protein D52 (TPD52) is overexpressed and a gene amplification target in ovarian cancer
Abstract
Recurrent chromosome 8q gain in ovarian carcinoma is likely to reflect the existence of multiple target loci, as the separate gain of chromosome bands 8q21 and 8q24 has been reported in independent studies. Since tumor protein D52 (TPD52) has been identified as a chromosome 8q21 amplification target in breast and prostate carcinoma, we compared TPD52 expression in normal ovarian epithelium (n = 9), benign serous adenomas (n = 11), serous borderline tumors (n = 6) and invasive carcinomas of the major histologic subtypes (n = 57) using immunohistochemistry. These analyses revealed that all normal ovarian epithelium samples and benign serous tumors were predominantly TPD52-negative, whereas TPD52 was overexpressed in most (44/57; 77%) ovarian carcinomas regardless of histologic subtype. TPD52 subcellular localization was predominantly cytoplasmic, although nuclear localization was also frequently observed in mucinous and clear cell carcinomas. In an independent cohort of stage III serous carcinomas (n = 18), we also directly compared in situ TPD52 expression using immunohistochemistry and TPD52 copy number using interphase FISH analyses. This revealed that TPD52 dosage and TPD52 expression were significantly positively correlated. TPD52 therefore represents a novel molecular marker in ovarian cancer, which is broadly expressed across the different histologic subtypes and whose upregulation frequently reflects increased TPD52 copy number.
... Tumor protein D52 is a proto-oncogene overexpressed in PCa due to gene amplification of specific locus on chromosome 8q21 (Byrne et al. , 1995Rhodes et al. 2002). High expression of TPD52 in prostate, breast, ovarian and other cancers dysregulates apoptosis and cell migration (Byrne et al. 2005;Rubin et al. 2004;Tennstedt et al. 2014;Ummanni et al. 2008). TPD52 (isoform 3) is a member of the tumor protein D52 family found in high copy numbers in advanced PCa causing growth and proliferation via targeting NF-κB transactivation (Dasari et al. 2017). ...
... Importantly, the oncogenic role of TPD52 inactivated AMPK via inhibition of its upstream kinase LKB1 through its direct interaction. TPD52 is one of the six oncogenes associated with PCa progression (Ross-Adams et al. 2015) which promotes metastasis in various cancers and its expression positively correlates with the growth of cancer cells and determines apoptosis (Byrne et al. 2005;Chen et al, 2021;Dasari et al. 2019;Dasari et al. 2017;Wang et al. 2004). Clinical testing of tissue samples also reported consistent elevated levels of TPD52 in localized and metastatic prostate cancer (Rubin et al. 2004). ...
... Tumor protein D52 is a proto-oncogene overexpressed in PCa due to gene amplification of specific locus on chromosome 8q21 (Byrne et al. , 1995Rhodes et al. 2002). High expression of TPD52 in prostate, breast, ovarian and other cancers dysregulates apoptosis and cell migration (Byrne et al. 2005;Rubin et al. 2004;Tennstedt et al. 2014;Ummanni et al. 2008). TPD52 (isoform 3) is a member of the tumor protein D52 family found in high copy numbers in advanced PCa causing growth and proliferation via targeting NF-κB transactivation (Dasari et al. 2017). ...
... Importantly, the oncogenic role of TPD52 inactivated AMPK via inhibition of its upstream kinase LKB1 through its direct interaction. TPD52 is one of the six oncogenes associated with PCa progression (Ross-Adams et al. 2015) which promotes metastasis in various cancers and its expression positively correlates with the growth of cancer cells and determines apoptosis (Byrne et al. 2005;Chen et al, 2021;Dasari et al. 2019;Dasari et al. 2017;Wang et al. 2004). Clinical testing of tissue samples also reported consistent elevated levels of TPD52 in localized and metastatic prostate cancer (Rubin et al. 2004). ...
Tumor protein D52 (TPD52) is a proto-oncogene overexpressed in prostate cancer (PCa) due to gene amplification and it is involved in the cancer progression of many cancers including PCa. However, the molecular mechanisms underlying the role of TPD52 in cancer progression are still under investigation. In this study, we report that the activation of AMP-activated protein kinase (AMPK) by AICAR (5-Aminoimidazole-4-carboxamide ribonucleotide) inhibited the LNCaP and VCaP cells growth by silencing TPD52 expression. Activation of AMPK inhibited the proliferation and migration of LNCaP and VCaP cells. Interestingly, AICAR treatment to LNCaP and VCaP cells led to the downregulation of TPD52 via activation of GSK3β by a decrease of inactive phosphorylation at Ser9. Moreover, in AICAR treated LNCaP cells, inhibition of GSK3β by LiCl attenuated downregulation of TPD52 indicating that AICAR acts via GSK3β. Furthermore, we found that TPD52 interacts with serine/threonine kinase 11 or Liver kinase B1 (LKB1) a known tumor suppressor and an upstream kinase for AMPK. The molecular modeling and MD simulations indicates that the interaction between TPD52 and LKB1 leads to inhibition of the kinase activity of LKB1 as its auto-phosphorylation sites were masked in the complex. Consequently, TPD52-LKB1 interaction may lead to inactivation of AMPK. Moreover, overexpression of TPD52 is found to be responsible for the reduction of pLKB1 (Ser428) and pAMPK (Thr172). Therefore, TPD52 may be playing its oncogenic role via suppressing the AMPK activation. Altogether, our results revealed a new mechanism of PCa progression in which TPD52 overexpression inhibits AMPK activation by interacting with LKB1. These results support that the use of AMPK activators and/or small molecules that could disrupt the TPD52-LKB1 interaction might be useful to suppress PCa cell growth.Graphical abstract
TPD52 interacts LKB1 and interfere with activation of AMPK in PCa cells
... TPD52 was identified more than 25 years ago [7] and revealed through overexpression of its coding gene in breast and lung cancer [7,8]. Other family members, such as TPD53 (also known as TPD52L1), TPD54 (TPD52L2), and TPD55 (TPD52L3), have been reported to be highly expressed in ovary [9][10][11], testis [12,14], colon [15,16], and prostate cancer [2,15], as well as in brain tumors [16], lymphoma [17], and leukemias [17,18]. We reported that TPD54 is a negative regulator of extracellularmatrix-dependent migration and cell attachment in oral squamous carcinoma cells [19]. ...
... HIF is reportedly involved in the growing malignancy of various cancer cells through upregulation of survivability under hypoxia [33] and is thought to be a molecular target for cancer therapeutics [36]. However, several groups, including ours, have studied the role of TPD52 in the proliferation and survival of various cancer cells [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. ...
Background
Tumor protein D52 (TPD52) reportedly plays an important role in the proliferation and metastasis of various cancer cells, including oral squamous cell carcinoma (OSCC) cells, and is expressed strongly at the center of the tumor, where the microenvironment is hypoxic. Thus, the present study investigated the roles of TPD52 in the survival and death of OSCC cells under hypoxia, and the relationship with hypoxia-inducible factor (HIF). We examined the expression of TPD52 in OSCC cells under hypoxic conditions and analyzed the effects of HIF on the modulation of TPD52 expression. Finally, the combinational effects of TPD52 knockdown and HIF inhibition were investigated both in vitro and in vivo.
Results
The mRNA and protein levels of TPD52 increased in OSCC cells under hypoxia. However, the increase was independent of HIF transcription. Importantly, the observation was due to upregulation of mRNA stability by binding of mRNA to T-cell intercellular antigen (TIA) 1 and TIA-related protein (TIAR). Simultaneous knockdown of TPD52 and inhibition of HIF significantly reduced cell viability. In addition, the in vivo tumor-xenograft experiments showed that TPD52 acts as an autophagy inhibitor caused by a decrease in p62.
Conclusions
This study showed that the expression of TPD52 increases in OSCC cells under hypoxia in a HIF-independent manner and plays an important role in the proliferation and survival of the cells in concordance with HIF, suggesting that novel cancer therapeutics might be led by TPD52 suppression.
... TPD52 was identi ed more than 25 years ago [7] and revealed through overexpression of its coding gene in breast and lung cancer [7,8]. Other family members, such as TPD53 (also known as TPD52L1), TPD54 (TPD52L2), and TPD55 (TPD52L3), have been reported to be highly expressed in ovary [9][10][11], testis [12,14], colon [15,16], and prostate cancer [2,15], as well as in brain tumors [16], lymphoma [17], and leukemias [17,18]. We reported that TPD54 is a negative regulator of extracellular-matrixdependent migration and cell attachment in oral squamous carcinoma cells [19]. ...
... HIF is reportedly involved in the growing malignancy of various cancer cells through upregulation of survivability under hypoxia [32] and is thought to be a molecular target for cancer therapeutics [35]. However, several groups, including ours, have studied the role of TPD52 in the proliferation and survival of various cancer cells [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. In the present study, we focused on the roles of TPD52 in OSCC cells under hypoxia. ...
Background. Tumor protein D52 (TPD52) reportedly plays an important role in the proliferation and metastasis of various cancer cells, including oral squamous cell carcinoma (OSCC) cells, and is expressed strongly at the center of the tumor, where the microenvironment is hypoxic. Thus, the present study investigated the roles of TPD52 in the survival and death of OSCC cells under hypoxia, and the relationship with hypoxia-inducible factor (HIF). We examined the expression of TPD52 in OSCC cells under hypoxic conditions and analyzed the effects of HIF on the modulation of TPD52 expression. Finally, the combinational effects of TPD52 knockdown and HIF inhibition were investigated both in vitro and in vivo.
Results. The mRNA and protein levels of TPD52 increased in OSCC cells under hypoxia. However, the increase was independent of HIF transcription. Importantly, the observation was due to upregulation of mRNA stability by binding of mRNA to T-cell intercellular antigen (TIA) 1 and TIA-related protein (TIAR). Simultaneous knockdown of TPD52 and inhibition of HIF significantly reduced cell viability. In addition, the in vivo tumor-xenograft experiments showed that TPD52 acts as an autophagy inhibitor caused by a decrease in p62.
Conclusions. This study showed that the expression of TPD52 increases in OSCC cells under hypoxia in a HIF-independent manner and plays an important role in the proliferation and survival of the cells in concordance with HIF, suggesting that novel cancer therapeutics might be led by TPD52 suppression.
... In breast cancer, multiple genes localized in the 8q12.1 -8q24. 23 interval were found to be amplified, including RRM2B [14]. Most RRM2B amplifications are accompanied by MYC amplifications, and these two genes are located in close proximity [15]. ...
... While multiple studies have observed the amplification of the 8q region, currently the frequency and specificity of these amplifications is not known, and more specifically, the consequence of RRM2B amplification with MYC or as independent from MYC amplification is not clearly understood [14,[17][18][19][20][21][22][23][24][25][26]. ...
RRM2B plays a crucial role in DNA replication, repair and oxidative stress. While germline RRM2B mutations have been implicated in mitochondrial disorders, its relevance to cancer has not been established. Here, using TCGA data, we investigated RRM2B alterations in cancer. We found that RRM2B is highly amplified in multiple tumor types, particularly in MYC-amplified tumors, and is associated with increased RRM2B mRNA expression. We also observed that the chromosomal region 8q22.3-8q24, is amplified in multiple tumors, and includes RRM2B, MYC along with several other cancer-associated genes. An analysis of genes within this 8q-amplicon showed that cases that have both RRM2B-amplified along with MYC have a distinct pattern of amplification compared to unaltered cases or cases that have amplifications in RRM2B or MYC only. These other 8q-proteins were shown to interact functionally within the RRM2B network of DNA repair, hypoxia and apoptosis regulating proteins. Notably, RRM2B-amplified tumors are characterized by mutation signatures of defective DNA repair and oxidative stress, and in some cancers also associated with poor clinical outcome. These findings suggest that some cancers may require RRM2B for cellular survival, providing novel therapeutic opportunities in these cancers.
... Tumor protein D52-like 2, known as hD54 in previous studies (Tpd52l2), is a member of the TPD52 family which has been implicated in multiple human cancers (18)(19)(20). Further research has demonstrated that the TPD52 gene encodes regulators of cancer cell proliferation, indicating that TPD52 may be important for maintaining tumorigenesis and metastasis of cancer cells (21). ...
... Luciferase activity assay, qRT-PCR and western blot assay further confirmed that Tpd52l2 is a target gene of miR-217. Tpd52l2 is a member of the TPD52 family which has been implicated in multiple human cancers (18)(19)(20). Studies have demonstrated that TPD52 may be important for maintaining tumorigenesis and metastasis of cancer cells (21). ...
MicroRNAs (miRNAs) play important roles in the regulation of various tumor biological processes including proliferation and apoptosis. miR-217 has been implicated in many types of cancer, whereas its expression and potential biological function in human pancreatic adenocarcinoma (HPAC) remain unclear. We aimed to investigate the clinical significance of miR-217 in patients with pancreatic carcinoma and its role and underlying molecular mechanism in HPAC. We collected 15 pairs of pancreatic cancer and normal pancreas tissues to evaluate the expression of miR-217 and tumor protein D52-like 2 (Tpd52l2). Then, we transfected AsPC-1 cells with miR-217 mimics or Tpd52l2 siRNA to detect the effect on cell proliferation, apoptosis, invasion, migration and the cell cycle. In addition, miR-217 mimics and Tpd52l2 expression plasmids were co-transfected into AsPC-1 cells to further investigate the mechanism of miR-217 and Tpd52l2 in HPAC tumorigenesis. Finally, exploration of related signaling pathways was carried out. Herein, we found that the expression of miR-217 was significantly downregulated in HPAC tissues as compared with that observed in adjacent normal tissues. Further functional assays showed that restoration of the expression of miR-217 inhibited cell proliferation, invasion and migration, induced apoptosis, and caused cell cycle arrest of HPAC cells. Notably, Tpd52l2 was identified as a functional target of miR-217 in HPAC. Furthermore, an inverse correlation between miR-217 and Tpd52l2 expression was observed in the HPAC tissues. Downregulation of Tpd52l2 had an effect similar to that following overexpression of miR-217, and upregulation of Tpd52l2 reversed the effects of the overexpression of miR-217. Finally, we found that overexpression of miR-217 or knockdown of Tpd52l2 suppressed the PIK3CA/AKT signaling pathways. In addition, this may explain the effect of miR-217/Tpd52l2 on HPAC development. Taken together, these results suggest a critical role of miR-217 in suppressing proliferation, migration and invasion of HPAC cells by targeting Tpd52l2. Targeting the miR-217/Tpd52l2 axis may be a new therapeutic application with which to treat patients with HPAC in the future.
... 6 A recent study on PCa patients using integrative analysis of copy number alterations (CNA) and array transcriptomics confirmed that TPD52 is one of the six oncogenes associated with PCa. 2 It is involved in vesicle trafficking, cell survival, proliferation, DNA repair, exocytosis, migration, and invasion. [7][8][9][10][11][12][13] It has been reported already that TPD52 is overexpressed in different cancers such as breast, 14 prostate, 15 and ovarian cancer 13 due to gene amplification. In LNCaP cells, expression of TPD52 family proteins is controlled by androgens and interleukin (IL)-6, thereby controlling cell proliferation and apoptosis. ...
... 6 A recent study on PCa patients using integrative analysis of copy number alterations (CNA) and array transcriptomics confirmed that TPD52 is one of the six oncogenes associated with PCa. 2 It is involved in vesicle trafficking, cell survival, proliferation, DNA repair, exocytosis, migration, and invasion. [7][8][9][10][11][12][13] It has been reported already that TPD52 is overexpressed in different cancers such as breast, 14 prostate, 15 and ovarian cancer 13 due to gene amplification. In LNCaP cells, expression of TPD52 family proteins is controlled by androgens and interleukin (IL)-6, thereby controlling cell proliferation and apoptosis. ...
Our previous study showed that TPD52 overexpression could increase migration and proliferation of LNCaP cells contributing to the development of prostate cancer. However, mechanism of TPD52 in prostate cancer initiation and progression remains elusive. In this study, we investigated the possible underlying mechanism of TPD52 in prostate cancer progression. In LNCaP cells, TPD52 expression was altered by transfecting with either EGFP-TPD52 or specific short hairpin RNA. Overexpression of TPD52 protected LNCaP cells from apoptosis through elevated anti-apoptotic proteins XIAP, Bcl-2, and Cyclin D1, whereas Bax was downregulated. Mechanistically, we found that TPD52 confers transactivation of nuclear factor-κB, thereby enhancing its target gene expression in LNCaP cells. TPD52 promotes LNCaP cell invasion probably via increased matrix metalloproteinase 9 expression and its activity while tissue inhibitor of metalloproteinase expression is significantly downregulated. Notably, TPD52 might be involved in cell adhesion, promoting tumor metastasis by inducing loss of E-cadherin, expression of vimentin and vascular cell adhesion molecule, and additionally activation of focal adhesion kinase. Furthermore, TPD52 directly interacts with nuclear factor-κB p65 (RelA) and promotes accumulation of phosphorylated nuclear factor-κB (p65)S536 that is directly linked with nuclear factor-κB transactivation. Indeed, depletion of TPD52 or inhibition of nuclear factor-κB in TPD52-positive cells inhibited secretion of tumor-related cytokines and contributes to the activation of STAT3, nuclear factor-κB, and Akt. Interestingly, in TPD52 overexpressing LNCaP cells, nuclear factor-κB inhibition prevented the autocrine/paracrine activation of STAT3. TPD52 activates STAT3 through ascertaining a cross talk between the nuclear factor-κB and the STAT3 signaling systems. Collectively, these results reveal mechanism by which TPD52 is associated with prostate cancer progression and highlight the approach for therapeutic targeting of TPD52 in prostate cancer.
... The first identified protein of this family, TPD52, was found to be overexpressed in breast and lung cancers (6,7). Other family members have also been reported to be highly expressed in colon (8,9), ovary (10)(11)(12), testis (5,13), prostate (14), and breast (15)(16)(17) cancers. Previous reports showed that overexpression of tpd52 in non-malignant 3T3 fibroblasts induces malignant transformation and increases cell proliferation and anchorageindependent growth (18,19). ...
... Tumor protein D52 (TPD52) family members are expressed in several types of cancers, including OSCC (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). Additionally, the cellular functions of this family have been widely studied. ...
The tumor protein D52 (TPD52) protein family includes TPD52, -53, -54 and -55. Several reports have shown important roles for TPD52 and TPD53, and have also suggested the potential involvement of TPD54, in D52-family physiological effects. Therefore, we performed detailed expression analysis of TPD52 family proteins in oral squamous cell carcinoma (OSCC). Towards this end, TPD54-overexpressing or knocked-down cells were constructed using OSCC-derived SAS, HSC2 and HSC3 cells. tpd52 or tpd53 was expressed or co-expressed in these cells by transfection. The cells were then analyzed using cell viability (MTT), colony formation, migration, and invasion assays. In OSCC-xenograft experiments, the cells were transplanted into nude mice together with injection of anti-tpd siRNAs. MTT assay of cell monolayers showed little differences in growth of the transfected cells. tpd54 overexpression in SAS cells significantly decreased colony formation in an anchorage-independent manner. Additionally, knock-down of tpd54 enhanced the number of colonies formed and overexpression of tpd52 in tpd54 knock-down cells increased the size of the colonies formed. The chemotaxis assay showed that tpd54 overexpression decreased cell migration. In the OSCC-xenograft in vivo study, tpd54 overexpression slightly attenuated tumor volume in vivo, despite the fact that tumor metastasis or cell survival was not involved. Our results showed that TPD54 not only downregulated anchorage-independent growth and cell migration in vitro, but also attenuated tumor growth in vivo. Based on these results, it is considered that TPD54 might act as a negative regulator of tumor progression in OSCC cells.
... 8,39 TPD52 overexpression has been demonstrated in many human malignancies including for example breast, [40][41][42] prostate, [43][44][45] and ovarian carcinomas. 46 Expression microarray and other molecular expression analyses predict TPD52 overexpression in most cancers, adding to the list multiple myeloma, 47,48 Burkitt's lymphoma, 49,50 pancreatic cancer, 51 testicular germ cell tumors, [52][53][54] and melanomas, 55,56 as well as multiple other adult and pediatric cancers. 39 TPD52 was first discovered in breast and prostate cancers owing to the large body of work in these two cancer types relative to expression and function. ...
Overexpressed tumor-associated antigens (TAAs) are a large group that includes proteins found at increased levels in tumors compared to healthy cells. Universal tumor expression can be defined as overexpression in all cancers examined as has been shown for Tumor Protein D52. TPD52 is an over expressed TAA actively involved in transformation, leading to increased proliferation and metastasis. TPD52 overexpression has been demonstrated in many human adult and pediatric malignancies. The murine orthologue of TPD52 (mD52) parallels normal tissue expression patterns and known functions of human TPD52 (hD52). Here in we present our preclinical studies over the past 15 years which have demonstrated that vaccine induced immunity against mD52 is effective against multiple cancers in murine models, without inducing autoimmunity against healthy tissues and cells.
... Importantly, it has been reported in many cancers that D52 is overexpressed and required for tumor progression. [7][8][9][10][11][12][13][14] The murine orthologue of D52 (mD52) is 86% identical to human D52 (hD52) at the amino acid level, providing a unique opportunity to study D52 cancer vaccine approaches and immune responses to D52 in murine models of cancer. Our vaccination efforts targeting D52 have been successful in murine models without inducing autoimmunity. ...
Cancer immunotherapy is a powerful tool for inducing antigen-specific antitumor cytotoxic T lymphocytes (CTLs). Next-generation strategies may include vaccination against overexpressed oncogenic tumor-self antigens. Previously, we reported vaccination against the oncogenic tumor-self antigen D52 (D52) was effective in preventing tumor growth. We recently reported that D52-vaccinated IL-10-deficient mice generated a significant memory response against tumor recurrence compared to wild-type mice and that vaccine-induced CD8+ IL-10+ T cells may possess regulatory function. Herein, we extended these studies by testing the hypothesis that D52-vaccine-elicited CD8+ IL-10+ T cells represent a distinct T cell population with a regulatory phenotype. C57Black/6J mice deficient in IL-10 or IFN-γ were vaccinated with the murine orthologue of D52; vaccination of wild-type (wt) mice served as a control for comparison. T cells were isolated from all three groups of vaccinated mice, and RNA was extracted from purified CD8+ T cells for deep sequencing and expression analysis. Chemokine receptor 8 (CCR8) and inducible co-stimulator (ICOS) were overexpressed in CD8+ T cells that produced IL-10 but not IFN-γ. These surface markers are associated with IL-10 producing CD4+ T regulatory cells thus supporting the possibility that CD8+ IL-10+ T cells elicited by D52 vaccination represent a unique regulatory T cell subset. The current phenotypic analyses of D52 vaccine elicited CD8+ T cells strengthen our premise that CD8+ IL-10+ T cells elicited by D52 tumor-self protein vaccination likely contribute to the suppression of memory CTL responses and inhibition of durable tumor immunity.
... Expression patterns of the tumor protein TP D52 family, including TPD52, TPD53, TPD54, and TPD55, have been investigated in malignant tumors. TPD52, also known as CRHSP-28m, was first identified as a chromosome 8q21 amplification target in breast cancer and was subsequently detected in lung, prostate, ovarian, endometrial, and hepatic cancers 6 . TPD53 has been identified as a novel 14-3-3-binding partner in breast cancer, with the highest level of expression observed at the G2-M transition ; dysregulated expression of TPD53 results in incomplete mitosis 7 . ...
A definitive diagnosis of salivary gland tumors is extremely difficult to make without evaluating the entire tumor and conducting immunohistochemical examinations. In this study, we aimed to examine and compare the expression patterns of the tumor protein （TP） D52 family, including TPD52, TPD53, and TPD54, in salivary gland tumor cells by using immunohistochemical staining. Among over 30 benign and malignant salivary gland tumors with extensive and diverse morphological features and overlapping histological similarities, we selected Warthin’s tumor and pleomorphic adenoma to represent benign salivary gland tumors and mucoepidermoid carcinoma to represent malignant ones. Tumor samples were fixed in 10％ buffered formalin and embedded in paraffin. Then, immunohistochemical staining was performed using antibodies against TPD52, TPD53, and TPD54. Neither the benign salivary gland tumors nor mucoepidermoid carcinoma stained for TPD52. However, the intensity of TPD53 and TPD54 staining was found to be low in the benign salivary gland tumors and high in mucoepidermoid carcinoma. TPD54 may serve as a pathological indicator of benign salivary gland tumors and mucoepidermoid carcinoma.
... Tumor protein D52-like 2 (TPD52L2), also called TPD54, belongs to the family of tumor protein D52 (TPD52) [2]. e elevated expression level of TPD52 has been associated with a variety of human carcinomas such as ovarian carcinoma [3], prostate carcinoma [4], and breast carcinoma [5]. An elevated TPD52 expression was found to be increasing colony formation, cell proliferation, and tumor migration/invasion [6,7]. ...
Tumor protein D52-like 2 or simply TPD52L2 belongs to the TPD52 family which has been implicated in a variety of human carcinomas. However, the TPD52L2 function in the gastric carcinoma oxaliplatin (OXA) resistance remains elusive. The main objective of this study is to evaluate the TPD52L2 effect in OXA-resistant gastric carcinoma cells in vitro. Oxaliplatin-resistant gastric carcinoma cells were generated in MGC-803 and SGC-7901 cells. siRNA-mediated knockdown of TPD52L2 was investigated in OXA-resistant MGC-803-OXA and SGC-7901-OXA cells. qRT-PCR was performed to assess the expression level of TPD52L2 mRNA. TPD52L2 protein expression level, apoptosis, and endoplasmic reticulum (ER) stress-associated proteins were identified via immunoblotting analysis. MTT assay was conducted for the evaluation of cell viability, while colony-forming activity was carried out via crystal violet staining. SGC-7901-OXA and MGC-803-OXA cells were found to be more resistant to OXA, as compared to the parental cell lines. The expression of TPD52L2 was found to be upregulated in OXA-resistant cells. Knockdown of TPD52L2 suppressed cell colony-forming potency, cell growth, and development in OXA-resistant cells. TPD52L2 knockdown also enhanced the PARP and caspase-3 cleavage. ER-associated proteins such as PERK, GRP78, CHOP, and IRE1α were found to be elevated in TPD52L2 knockdown cells. ER stress might be involved in TPD52L2 knockdown-induced apoptosis in OXA-resistant gastric carcinoma cells.
... It seemed that OCLN and TPD52 may be the most promising biomarker for detecting OC patients. At present, some literatures have reported that TPD52 is highly expressed in ovarian cancer tissues (Byrne et al., 2005) and acts as a downstream signal molecule in some processes (Liu and Xi, 2020), indicating that TPD52 also plays an important role in the occurrence and development of ovarian cancer, and MAL2 and TPD52 are chaperones. They are likely to play a synergistic role in the occurrence and development of ovarian cancer. ...
Recent studies have reported that T-cell differentiation protein 2 (MAL2) is an important regulator in cancers. Here, we downloaded data from multiple databases to analyze MAL2 expression and function in pan-cancers, especially in ovarian cancer (OC). Gene Expression Profiling Interactive Analysis (GEPIA) databases was used to examine MAL2 expression in 13 types of cancer. Kaplan–Meier plotter database was used to analyze the overall survival rate of MAL2 in pan-cancers. The Catalog of Somatic Mutations in Cancer (COSMIC), cBioPortal, and UCSC databases were used to examine MAL2 mutation in human cancers. Metascape, STRING, and GeneMANIA websites were used to explore MAL2 function in OC. Furthermore, ggplot2 package and ROC package were performed to analyze hub gene expression and undertake receiver operating characteristic (ROC) analysis. Drug sensitivity of MAL2 in OC was examined by the GSCALite database. In order to verify the results from databases above, real-time quantitative polymerase chain reaction (qRT-PCR) and western blotting were conducted to detect the expression of MAL2 in OC cells. CRISPR/Cas9 system was used to knockout the MAL2 gene in the OC cell lines HO8910 and OVCAR3, using specific guide RNA targeting the exons of MAL2. Then, we performed proliferation, colony formation, migration, and invasion assays to investigate the impact of MAL2 in OC cell lines in vivo and in vitro . Epithelial-mesenchymal transition (EMT)-associated biomarkers were significantly altered in vitro via western blotting and qRT-PCR. Taken together, we observed that MAL2 was remarkably dysregulated in multiple cancers and was related to patient overall survival (OS), mutation, and drug sensitivity. Furthermore, experimental results showed that MAL2 deletion negatively regulated the proliferation, migration, invasion, and EMT of OC, indicating that MAL2 is a novel oncogene that can activate EMT, significantly promote both the proliferation and migration of OC in vitro and in vivo , and provide new clues for treatment strategies.
... 24 However, whether circ-XIAP can modulate the resistance of PCa to DTX through interacting with miR-1182 is still unclear. Tumor protein D52 (TPD52), a chromosome 8q21 amplification target, acts as an oncogene in many cancers, including PCa. 25,26 Coincidently, by bioinformatics analysis, we found that both circ-XIAP and 3ʹUTR of TPD52 had the complementary binding sequence for miR-1182, which suggested the interactions among circ-XIAP, miR-1182 and TPD52 in DTX resistance of PCa. ...
Background:
Exosomal circular RNAs (circRNAs) are involved in the pathogenesis of prostate cancer (PCa) and chemotherapy resistance. This research aimed to explore the function and molecular mechanism of circRNA X-linked inhibitor of apoptosis (circ-XIAP) in docetaxel (DTX) resistance of PCa.
Methods:
The expression of circ-XIAP, microRNA-1182 (miR-1182), tumor protein D52 (TPD52) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Exosomes were detected with transmission electron microscopy (TEM). Cluster of differentiation 63 (CD63), cluster of differentiation 9 (CD9) and TPD52 protein levels were detected by Western blot (WB). FIfty percent inhibitory concentration (IC50) of DTX and cell viability were determined using Cell Counting Kit-8 (CCK-8) assay. Colony formation assay was applied to assess colony-forming ability. Cell cycle distribution and apoptosis were analyzed by flow cytometry. Transwell assay was used for measuring cell migration and invasion. Dual-reporter luciferase assay was performed to confirm the interaction between miR-1182 and circ-XIAP or TPD52. The role of circ-XIAP in vivo was confirmed via the mice xenograft model.
Results:
Circ-XIAP and TPD52 were upregulated and miR-1182 was downregulated in DTX-resistant PCa tissue specimens and cell lines. Circ-XIAP was also overexpressed in exosomes from DTX-resistant cells and could be transmitted via exosomes. Circ-XIAP knockdown enhanced DTX sensitivity by suppressing DTX-resistant cell proliferation, migration and invasion and inducing cell cycle arrest and apoptosis. Circ-XIAP directly targeted miR-1182, and the effects of circ-XIAP knockdown were reversed by downregulating miR-1182 in DTX-resistant cells. TPD52 was the target of miR-1182, and its upregulation weakened the promotive effect of miR-1182 on DTX sensitivity. Importantly, circ-XIAP depletion inhibited tumor growth and increased DTX sensitivity in vivo.
Conclusion:
Exosomal circ-XIAP promoted DTX resistance of PCa by regulating miR-1182/TPD52 axis, providing a promising therapeutic target for PCa chemotherapy.
... However, RRM2B amplifications also occur independent of MYC amplifications, albeit at a lower frequency (Kalkat et al., 2017). While multiple studies have observed the amplification of the 8q region, currently the frequency and specificity of these amplifications is not known, and more specifically, the consequence of RRM2B amplification with MYC or as independent from MYC amplification is not clearly understood (Bruch et al., 1998;Sato et al., 1999;Saha et al., 2001;Byrne et al., 2005;Ehlers et al., 2005;Ho et al., 2006;Schleicher et al., 2007;Bilal et al., 2012;Parris et al., 2014;Yong et al., 2014;Kwon et al., 2017). ...
RRM2B plays a crucial role in DNA replication, repair and oxidative stress. While germline RRM2B mutations have been implicated in mitochondrial disorders, its relevance to cancer has not been established. Here, using TCGA studies, we investigated RRM2B alterations in cancer. We found that RRM2B is highly amplified in multiple tumor types, particularly in MYC-amplified tumors, and is associated with increased RRM2B mRNA expression. We also observed that the chromosomal region 8q22.3–8q24, is amplified in multiple tumors, and includes RRM2B, MYC along with several other cancer-associated genes. An analysis of genes within this 8q-amplicon showed that cancers that have both RRM2B-amplified along with MYC have a distinct pattern of amplification compared to cancers that are unaltered or those that have amplifications in RRM2B or MYC only. Investigation of curated biological interactions revealed that gene products of the amplified 8q22.3–8q24 region have important roles in DNA repair, DNA damage response, oxygen sensing, and apoptosis pathways and interact functionally. Notably, RRM2B-amplified cancers are characterized by mutation signatures of defective DNA repair and oxidative stress, and at least RRM2B-amplified breast cancers are associated with poor clinical outcome. These data suggest alterations in RR2MB and possibly the interacting 8q-proteins could have a profound effect on regulatory pathways such as DNA repair and cellular survival, highlighting therapeutic opportunities in these cancers.
... While the role of the MYC gene as the driver of the 8q24 amplicon is well established, the genetic factor(s) contributing to the oncogenic potential of the 8q21 amplicon remains to be elucidated. It is reported that amplification of the gene encoding for WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) in this region is an oncogenic factor for breast cancer (6) and prostate cancer (7), while amplification of the gene encoding for tumor protein D52 (TPD52), whose function has rarely been studied, in 8q21 is implicated in the development of ovarian cancer (8) and lung cancer (9). Clearly, the molecular basis underlying the 8q21 amplicon in the development and progression of breast carcinogenesis needs further elucidation. ...
Copy number gain in chromosome 8q21 is frequently detected in breast cancer, yet the oncogenic potential underlying this amplicon in breast carcinogenesis remains to be delineated. We report here that ZNF704, a gene mapped to 8q21, is recurrently amplified in various malignancies including breast cancer. ZNF704 acted as a transcriptional repressor and interacted with the transcriptional corepressor SIN3A complex. Genome-wide interrogation of transcriptional targets revealed that the ZNF704/SIN3A complex represses a panel of genes including PER2 that are critically involved in the function of the circadian clock. Overexpression of ZNF704 prolonged the period and dampened the amplitude of the circadian clock. ZNF704 promoted the proliferation and invasion of breast cancer cells in vitro and accelerated the growth and metastasis of breast cancer in vivo. Consistently, the level of ZNF704 expression inversely correlated with that of PER2 in breast carcinomas, and high level of ZNF704 correlated with advanced histologic grades, lymph node positivity, and poor prognosis of patients with breast cancer, especially those with HER2+ and basal-like subtypes. These results indicate that ZNF704 is an important regulator of the circadian clock and a potential driver for breast carcinogenesis.
Significance
This study indicates that ZNF704 could be a potential oncogenic factor, disrupting circadian rhythm of breast cancer cells and contributing to breast carcinogenesis.
... TPD52 is a tumor-promoting gene and is frequently overexpressed in multiple cancers, such as ovarian cancer, 37 prostate cancer, 38 colorectal cancer. 39 Due to the oncogenic role of TPD52 in many cancers, TPD52 should be further studied. ...
Background
Long non-coding RNAs (lncRNAs) have been reported to play essential roles in regulating the radiosensitivity of cancers. Prostate cancer-associated transcript 6 (PCAT6) exerts oncogenic roles in several tumors. However, the roles of PCAT6 and its underlying mechanism in regulating the radiosensitivity of triple-negative breast cancer (TNBC) have not been investigated.
Methods
The expression levels of PCAT6, microRNA-185-5p (miR-185-5p) and tumor protein D52 (TPD52) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability, apoptosis and colony formation were assessed by Cell Counting Kit-8 (CCK-8) assay, flow cytometry and colony formation assay, respectively. The interaction between miR-185-5p and PCAT6 or TPD52 was predicted by bioinformatics analysis and verified by dual-luciferase reporter assay. Western blot was carried out to detect the protein level of TPD52.
Results
PCAT6 and TPD52 were highly expressed and miR-185-5p was lowly expressed in TNBC tissues and cells, which was associated with an aggressive tumor phenotype in patients, affecting lymph node metastasis and clinical stage. PCAT6 or TPD52 knockdown or miR-185-5p overexpression enhanced the radiosensitivity of TNBC cells via inhibiting proliferation and inducing apoptosis. PCAT6 directly interacted with miR-185-5p and negatively regulated miR-185-5p expression. Moreover, TPD52 was confirmed as a target of miR-185-5p. Besides, PCAT6 regulated the radiosensitivity of TNBC cells through acting as a molecular sponge of miR-185-5p to modulate TPD52 expression.
Conclusion
Knockdown of PCAT6 promoted the radiosensitivity of TNBC cells through regulating miR-185-5p/TPD52 axis, providing a vital theoretical basis to improve the radiotherapy efficiency of TNBC.
... TPD52 is a recently identified proto-oncogene, which was reported to be upregulated in several types of cancers. 24,25 Wu et al reported that inhibition of TPD52 could suppress cervical cancer cell proliferation and induce cell apoptosis. 26 Consistent with this, our results showed that TPD52 silencing inhibited, whereas TPD52 overexpression promoted cervical cell proliferation, migration, and invasion. ...
Objective
Long non-coding RNAs (lncRNAs) have been identified as important players in tumorigenesis. LncRNA highly upregulated in liver cancer (HULC) has been identified as a key regulator in the progression of various cancers. However, the functional role and the mechanisms of HULC in regulating cervical cancer cell behavior remain unclear.
Methods
HULC expression, miR-218 expression and TPD52 mRNA level in cervical cancer cells were examined by qRT-PCR. Cell proliferation was evaluated by MTT assay. Cell migration and invasion were examined by Transwell assay. TPD52 protein level was measured by Western blot. Dual-luciferase reporter assay was measured to verify the combination of HULC and miR-218 as well as miR-218 and TPD52.
Results
HULC expression was upregulated in cervical cancer cell lines, and HULC promoted cervical cancer cell proliferation, migration and invasion. Mechanistically, HULC acted as a sponge of miR-218 to elevate expression of TPD52, a target of miR-218, and thereby promoted cervical cancer cell proliferation, migration, and invasion.
Conclusion
HULC promotes cervical cancer cell proliferation, migration and invasion via miR-218/TPD52 axis.
... TPD52is a protein that is overexpressed in ovarian cancer. 81 The expression is ranging from absent in benign tumour to overexpression in all invasive samples. TPD52 was also found overexpressed in prostate cancer. ...
Cervical cancer is the third most common cancer affecting women worldwide. This occurs despite having precancerous screening and HPV vaccination implemented vigorously as a definitive intervention. Natural plant like Streblus asper has been discovered to offer great hope in treating and preventing cancers. In this study, we explored the potential of S.asper to inhibit the growth of cervical cancer cell line by using liquid chromatography mass spectrometry (LCMS). Upon analysis, seventy-six proteins that are common to both untreated and treated groups were identified. Of this, 14 proteins are found differentially expressed more than 2-fold changes. Based on past literature, we selected 7 proteins that are closely associated with treatment effects. These include Dermcidin, Keratin, type I cytoskeletal 9, Tropomyosin alpha-4 chain, Myristoylated alanine-rich C-kinase (MARCKS), Tumour protein D52, Folate receptor alpha, and Parathymosin. Pathway enrichment analysis by Reactome revealed 9 related pathways which include metabolism of protein, post-translational protein modification, signalling by Rho GTPases, signalling by NOTCH, cell cycle, cellular senescence, signalling by WNT, transcriptional regulation by TP53, and cellular responses to stress. These findings may improve our understanding on the related significant mechanism involving anti-cancer effects of S.asper on the cervical cancer cell line.
... Initially, it was found to be overexpressed due to gene amplification in breast cancer [7]. Subsequently, its overexpression was reported in the colon [8], prostate [9][10][11], lung [12,13], and ovarian [14] cancers. The overexpression of TPD52 murine orthologue (mD52) in 3T3 cells promoted the transformation of these murine fibroblast cells and induced the metastasis thereby cancer progression [15,16]. ...
Tumor protein D52 (TPD52) is overexpressed in multiple cancers including prostate cancer due to gene amplification and investigations to understand its role in the pathophysiology of different cancers are continuing. GST pull-down assays and Tandem affinity purification of TPD52 as bait identified novel prey Peroxiredoxin 1 (PRDX1) in prostate cancer (PCa) cells. PRDX1 interaction with TPD52 was confirmed in immunoprecipitation and affinity interaction assays. Mapping of interaction domain indicated that PRDX1 interacts with C-terminal region of TPD52 containing PEST domain between 152 and 179 amino acids, a new binding region of TPD52. Here we show that TPD52 interaction with PRDX1 increased its peroxidase activity and ectopic expression of TPD52 induced dimerization of PRDX1 in PCa cells. Moreover, H 2 O 2 exposure evoked the interaction between TPD52 and PRDX1 while depletion of both proteins led to the accumulation of H 2 O 2 suggesting peroxidase activity is important to maintain oxidative capacity in PCa cells. We also observed that overexpression or downregulation of TPD52 and PRDX1 individually or together affecting PCa cells growth, survival, and migration. Altogether, our results show a novel interaction partner of TPD52 providing new insights of its functions and ascertain the role of TPD52-PRDX1 interaction in PCa progression.
... TPD54 is a tumor protein which shares functional characteristics with tumor protein D52 (TPD52) [1,2,3]. TPD52 has been reported to be amplified in breast, ovarian, and prostate cancers and has also been associated with poor prognosis [4][5][6][7]. Its known functions involve the regulation of cell proliferation and migration [8][9][10]. ...
Background
The role of tumor protein D54 in breast cancer has not been studied and its function in breast cancer remains unclear. In our previous pharmacogenomic studies using lymphoblastoid cell line (LCL), this protein has been identified to affect metformin response. Although metformin has been widely studied as a prophylactic and chemotherapeutic drug, there is still a lack of biomarkers predicting the response to metformin in breast cancer. In this study, we revealed the novel function of TPD54 in breast cancer through understanding how TPD54 altered the cancer cell sensitivity to metformin.
Methods
The role of TPD54 in altering cellular sensitivity to metformin treatment was carried out by either knockdown or overexpression of TPD54, followed by measuring cell viability and reactive oxygen species (ROS) production in MCF7 breast cancer cell line and breast cancer patient-derived xenografts. Functional analysis of TPD54 in breast cancer cells was demonstrated by studying TPD54 protein localization and identification of potential binding partners of TPD54 through immunoprecipitation followed by mass spectrometry. The effect of TPD54 on pyruvate dehydrogenase (PDH) protein regulation was demonstrated by western blot, immunoprecipitation, and site-directed mutagenesis.
Results
TPD54 inhibited colony formation and enhanced cellular sensitivity to metformin treatment in MCF7 cells and breast cancer patient-derived xenografts. Mechanistic study indicated that TPD54 had mitochondrial localization, bound to and stabilized pyruvate dehydrogenase E1α by blocking pyruvate dehydrogenase kinase 1 (PDK1)-mediated serine 232 phosphorylation. TPD54 knockdown increased PDH E1α protein degradation and led to decreased PDH enzyme activity, which reduced mitochondrial oxygen consumption and reactive oxygen species (ROS) production, thus contributing to the resistance of breast cancer cells to metformin treatment.
Conclusion
We have discovered a novel mechanism by which TPD54 regulates pyruvate dehydrogenase and affects the sensitivity of breast cancer to metformin treatment. Our findings highlight the important post-translational regulation of PDK1 on PDH E1α and the potential application of TPD54 as a biomarker for selecting tumors that may be sensitive to metformin therapy. These provide new insights into understanding the regulation of PDH complexes and the resistance mechanisms of cancer cells to metformin treatment.
Electronic supplementary material
The online version of this article (10.1186/s40170-018-0193-4) contains supplementary material, which is available to authorized users.
... Of these, TPD52 was the first to be identified nearly 20 years ago as an overexpressed gene in breast cancers [8]; the gene is located on chromosome 8q21, a region frequently gained in various human cancers [9][10][11]. Thereafter, other members have also been reported to be highly expressed in various cancers, including prostate [12,13], testis [7,14], colon [15,16], ovary [17][18][19], breast [20][21][22], and oral [23,24] cancer cells. As such, it appears that TPD52 family proteins might play important roles in the invasion, growth, and metastasis of cancer cells. ...
The tumor protein D (TPD) family consists of four members, TPD52, TPD53, TPD54, and TPD55. The physiological roles of these genes in normal tissues, including epidermal and mesenchymal tissues, have rarely been reported. Herein, we examined the expression of TPD52 and TPD54 genes in cartilage in vivo and in vitro and investigated their involvement in the proliferation and differentiation of chondrocytes in vitro. TPD52 and TPD54 were uniformly expressed in articular cartilage and trabecular bone and were scarcely expressed in the epiphyseal growth plate. In MC3T3E-1 cells, the expressions of TPD52 and TPD54 were increased in a differentiation-dependent manner. In contrast, their expressions were decreased in ATDC5 cells. In ATDC5 cells, overexpression of TPD52 decreased alkaline phosphatase (ALPase) activity, while knock-down of TPD52 showed little effect. In contrast, overexpression of TPD54 enhanced ALPase activity, Ca ²⁺ deposition, and the expressions of type X collagen and ALPase genes, while knock-down of TPD54 reduced them. The results revealed that TPD52 inhibits and that TPD54 promotes the terminal differentiation of a chondrocyte cell line. As such, we report for the first time the important roles of TPD52 and TPD54, which work oppositely, in the terminal differentiation of chondrocytes during endochondral ossification.
... However, TPD52 gene showed overexpression and copy number increases in multiple human cancers [25] and its exogenous expression was associated with the increased anchorage-independent growth and cell proliferation [11,26,27], and metastasis in vivo in immunocompetent hosts [26]. It was indicated that TPD52 expression in ovarian cancer tissue was higher compared with normal ovarian epithelium [28], and TPD52 was found to be overexpressed in prostate cancer [29,30] and breast cancer [31,32]. Additionally, TPD52 overexpression in colorectal tissue samples was identified by MS analysis compared to normal tissue [33]. ...
The four-transmembrane protein MAL2 and tumor protein D52 (TPD52) have been shown to be involved in tumorigenesis of various cancers. However, their roles in colorectal cancer (CRC) remain unclear. In this study, we explored the expressions of MAL2 and TPD52 in tumor specimens resected from 123 CRC patients and the prognostic values of the two proteins in CRC. Immunohistochemical analyses showed that MAL2 (P<0.001) and TPD52 (P<0.001) were significantly highly expressed in primary carcinoma tissues compared with adjacent non-cancerous mucosa tissues. And TPD52 exhibited frequent overexpression in liver metastasis tissues relative to primary carcinoma tissues (P = 0.042), while MAL2 in lymphnode and liver metastasis tissues showed no significant elevation. Real-time quantitative PCR (RT-qPCR) showed the identical results. Correlation analyses by Pearson’s chi-square test demonstrated that MAL2 in tumors was positively correlated with tumor status (pathological assessment of regional lymph nodes (pN, P = 0.024)), and clinic stage (P = 0.017). Additionally, the expression of TPD52 was detected under the same condition and was shown to be positively correlated withtumor status (pathological assessment of the primary tumor (pT, P = 0.035), distant metastasis (pM, P = 0.001)) and CRC clinicopathology(P = 0.024). Kaplan-Meier survival curves indicated that positive MAL2 (P<0.001) and TPD52 (P<0.001) expressions were associated with poor overall survival (OS) in CRC patients. Multivariate analysis showed that MAL2 and TPD52 expression was an independent prognostic factor for reduced OS of CRC patients. Moreover, overexpression of TPD52 in CRC SW480 cells showed an increased cell migration (P = 0.023) and invasion (P = 0.012) through inducing occurrence of epithelial-mesenchymal transition (EMT) and activating focal adhesion kinase (FAK)-mediated integrin signalling and PI3K⁄Akt signalling.Whereas TPD52-depleted cells showed the reverse effect. These data suggested that MAL2 and TPD52 might be potential biomarkers for clinical prognosis and might be a promising therapeutic target for CRC.
... Emerin, as a member of the nuclear lamina-related family, may play a certain role in papillary thyroid carcinoma (42). The tumor protein D54 gene was first identified in human breast cancer (43), and then it was established that it is overexpressed in prostate and ovarian carcinomas (44)(45)(46)(47). Several studies have reported that HSP70 is frequently overexpressed in tumor cells, where it has anti-apoptotic functions and acts as a survival protein (48). ...
Ovarian cancer commonly presents without prominent symptoms and is consequently diagnosed at advanced stages with unfavorable prognosis. Novel serological biomarkers for the early detection and clinical management of ovarian cancer are imminently needed. Proteomic-based methods for biomarker discovery are promising strategies implemented in cancer research. The aim of the present study was to identify new tumor antigens from the ovarian cancer cell line SKOV3 and their associated autoantibodies in sera of patients with ovarian cancer employing proteomic-based approaches. Proteins from the ovarian cancer cell line SKOV3 were extracted by two‑dimensional polyacrylamide gel electrophoresis (2-DE) followed by western blotting and antibody reaction with sera from patients with ovarian cancer and normal controls. Positive spots were excised from Coomassie blue‑stained gels and identified by liquid chromatography‑tandem mass spectrometry (LC-MS/MS). The 2-DE analysis results revealed a total of 14 protein spots on the gel, and 7 proteins were finally identified by LC-MS/MS. In the subsequent experiment, using immunoassay on ovarian cancer sera and tissue-array slides, the well-known protein HSP70 was selected in order to validate this proteomic-based approach. In conclusion, the proteomic method used in the present study is a powerful instrument for identifying novel serum markers that may exhibit clinical usefulness in cancer.
... Human TPD52 was reported to be overexpressed in several human cancers, including breast cancer, 12 prostate cancer, 13 ovarian cancer, 14 pancreatic adenocarcinoma, 15 and other cancers. Several studies revealed that TPD52 acts as a tumor promoter by influencing cell survival, proliferation, migration, and invasion. ...
Background
Uterine leiomyoma is one of the most common benign tumors in women. It dramatically decreases the quality of life in the affected women. However, there is a lack of effective treatment paradigms. Micro-RNAs are small noncoding RNA molecules that are extensively expressed in organisms, and they are interrelated with the occurrence and development of the tumor. miR-139-5p was found to be downregulated in various cancers, but its function and mechanism in uterine leiomyoma remain unknown. The aim of this study was to investigate the role of miR-139-5p and its target gene in uterine leiomyoma.
Methods
By using a bioinformatic assay, it was found that TPD52 was a potential target gene of miR-139-5p. Then, expressions of miR-139-5p and TPD52 in uterine leiomyoma and adjacent myometrium tissues were evaluated by quantitative real-time polymerase chain reaction and Western blot. Proliferation, apoptosis, and cell cycle of uterine leiomyoma cells transfected by miR-139-5p mimics or TPD52 siRNA were determined.
Results
It was observed that the expression of miR-139-5p in uterine leiomyoma tissues was significantly lower (P<0.001) than that in the adjacent myometrium tissues. Overexpression of miR-139-5p inhibited the growth of uterine leiomyoma cells and induced apoptosis and G1 phase arrest. Dual-luciferase reporter assay and Western blot validated that TPD52 is the target gene of miR-139-5p. Furthermore, downregulation of TPD52 by siRNA in uterine leiomyoma cells inhibited cell proliferation and induced cell apoptosis and G1 phase arrest.
Conclusion
Data suggested that miR-139-5p inhibited the proliferation of uterine leiomyoma cells and induced cell apoptosis and G1 phase arrest by targeting TPD52.
... Interestingly, this gene is located on the human chromosome 8q21.13, a frequently observed region of chromosomal amplification in several types of cancers (31)(32)(33). In lung adenocarcinoma, chromosome 8q21.13, ...
The development of targeted molecular therapies has greatly benefited patients with lung adenocarcinomas. In contrast, these treatments have had little benefit in the management of lung squamous cell carcinoma (lung SCC). Therefore, new treatment options based on current genomic approaches are needed for lung SCC. Aberrant microRNA (miRNA) expression has been shown to promote lung cancer development and aggressiveness. Downregulation of microRNA-218 (miR-218) was frequently observed in our miRNA expression signatures of cancers, and previous studies have shown an antitumor function of miR-218 in several types of cancers. However, the impact of miR-218 on lung SCC is still ambiguous. The present study investigated the antitumor roles of miR-218 in lung SCC to identify the target genes regulated by this miRNA. Ectopic expression of miR-218 greatly inhibited cancer cell migration and invasion in the lung SCC cell lines EBC-1 and SK-MES-1. Through a combination of in silico analysis and gene expression data searching, tumor protein D52 (TPD52) was selected as a putative target of miR-218 regulation. Moreover, direct binding of miR-218 to the 3'-UTR of TPD52 was observed by dual luciferase reporter assay. Overexpression of TPD52 was observed in lung SCC clinical specimens, and knockdown of TPD52 significantly suppressed cancer cell migration and invasion in lung SCC cell lines. Furthermore, the downstream pathways mediated by TPD52 involved critical regulators of genomic stability and mitotic checkpoint genes. Taken together, our data showed that downregulation of miR-218 enhances overexpression of TPD52 in lung SCC cells, promoting cancer cell aggressiveness. Identification of tumor-suppressive miRNA-mediated RNA networks of lung SCC will provide new insights into the potential mechanisms of the molecular pathogenesis of the disease.
... However, its roles in cancer are controversial. TPD52 is overexpressed in several cancers, such as ovarian, breast, prostate, and pancreatic cancer, and multiple myeloma, Burkitt's lymphoma, and melanoma [23][24][25][26][27][28][29]. TPD52 is also down-regulated in certain tumors, such as papillary renal cell cancer, leiomyosarcoma, clear cell renal cell cancer, liposarcoma, and lung cancer [30]. ...
Tumor protein D52 (TPD52) has been indicated to be involved in tumorigenesis of various malignancies. But its role in hepatocellular carcinoma (HCC) is unknown. This study aimed to explore the expression of TPD52 in HCC samples and cell lines using real-time quantitative PCR, western blotting, and immunohistochemistry. The prognostic value of TPD52 in HCC was also analysed. Meanwhile, the mechanism of TPD52 in hepatocarcinogenesis was further investigated by western blotting, immunohistochemistry, over-express and knockdown studies. We found that TPD52 expression was significantly decreased in the HCC tissues and HCC cell lines. TPD52 expression was significantly correlated with tumor-nodes-metastasis (TNM) stage. Kaplan-Meier survival curves showed that high TPD52 expression was associated with improved overall survival (OS) and disease-free survival (DFS) in HCC patients. Multivariate analysis indicated that TPD52 expression was an independent prognostic marker for the OS and DFS of patients. In addition, TPD52 expression was positively correlated with p21 and p53 expression, and was negatively correlated with MDM2, BCL2 and P-GSK-3β expression in HCC. In conclusions, our findings suggested that TPD52 is a potential tumor suppressor in HCC. It may be a novel prognostic biomarker and molecular therapy target for HCC.
... Additionally, AnxA6 may promote the tumorigenesis of B-cell malignancies in association with TPD52. It has been previously observed that the overexpression of TPD52 contributes to the progression of BC, PCa and ovarian cancer (OC) (46)(47)(48), and acts as a marker to differentiate B cells from plasma cells (21). This hypothesis is supported by the fact that AnxA6 was coimmunoprecipitated with TPD52 in the Thiel human myeloma cell line in a Ca 2+ -dependent manner (21). ...
Annexin A6 (AnxA6) is a member of a conserved superfamily of Ca2+-dependent membrane-binding annexin proteins. It participates in membrane and cytoskeleton organization, cholesterol homeostasis, membrane trafficking, cell adhesion and signal transduction. The expression levels of AnxA6 are closely associated with melanoma, cervical cancer, epithelial carcinoma, breast cancer, gastric cancer, prostate cancer, acute lymphoblastic leukemia, chronic myeloid leukemia, large-cell lymphoma and myeloma. AnxA6 exhibits dual functions in cancer, acting either as a tumor suppressor or promoter, depending on the type of cancer and the degree of malignancy. In several types of cancer, AnxA6 acts via Ras, Ras/MAPK and/or FAK/PI3K signaling pathways by mainly mediating PKCα, p120GAP, Bcr-Abl and YY1. In the present review, the roles of AnxA6 in different types of cancer are summarized.
... The first TPD52 gene was identified as being over-expressed in human breast carcinomas [7]. Afterwards, the expression level of TPD52 was reported to be elevated in multiple human cancers, including lung [8, 9], prostate [10][11][12], colon [13], and ovary [14] . Further studies demonstrated that TPD52 gene encodes regulators of cancer cell proliferation, indicating that TPD52 may be important for maintaining tumorigenesis and metastasis of cancer cells [15]. ...
Tumor protein D52-like 2, known as hD54 in previous studies (TPD52L2), is a member of TPD52 family which has been implicated in multiple human cancers. In recent reports, TPD52 proteins were indicated to be associated with several malignancies, but very little is known about the function of TPD52L2 in liver cancers. In our present study, in order to explore the role of TPD52L2 in liver cancer, TPD52L2 was knocked down in SMMC-7721 liver cancer cell line by lentivirus mediated RNA interference. The results demonstrated that depletion of TPD52L2 could remarkably inhibit proliferation and colony forming ability of cancer cell SMMC-7721. Furthermore, cell cycle in TPD52L2 depleted cells was verified to be arrested in G0/G1 phase as determined by FACS assay, in consistence with the observation of cell proliferation inhibition. These results unraveled that TPD52L2 played an important role in tumorigenesis pathways of liver cancer and might serve as a promising target in human liver cancer diagnosis and therapy.
... TPD52 overexpression has been demonstrated in several human malignancies including breast, [76][77][78] prostate, [79][80][81] and ovarian carcinomas. 82 Expression microarray and other analyses predict TPD52 overexpression in many other cancers including multiple myeloma, 83,84 Burkitt's lymphoma, 85,86 pancreatic cancer, 87 testicular germ cell tumors, [88][89][90] and melanomas, 91,92 as well as multiple other adult and pediatric cancers. 93 Murine ortholog of TPD52 The murine ortholog of TPD52 (mD52) parallels normal tissue expression patterns and known functions of human TPD52 (hD52), with 86% amino acid identity. ...
Overexpressed tumor-self antigens represent the largest group of candidate vaccine targets. Those exhibiting a role in oncogenesis may be some of the least studied but perhaps most promising. This review considers this subset of self antigens by highlighting vaccine efforts for some of the better known members and focusing on TPD52, a new promising vaccine target. We shed light on the importance of both preclinical and clinical vaccine studies demonstrating that tolerance and autoimmunity (presumed to preclude this class of antigens from vaccine development) can be overcome and do not present the obstacle that might have been expected. The potential of this class of antigens for broad application is considered, possibly in the context of low tumor burden or adjuvant therapy, as is the need to understand mechanisms of tolerance that are relatively understudied.
... However, its roles in cancer are controversial. TPD52 is overexpressed in several cancers, such as ovarian, breast, prostate, and pancreatic cancer, and multiple myeloma, Burkitt's lymphoma, and melanoma [23][24][25][26][27][28][29]. TPD52 is also down-regulated in certain tumors, such as papillary renal cell cancer, leiomyosarcoma, clear cell renal cell cancer, liposarcoma, and lung cancer [30]. ...
Tripartite motif-containing 3 (TRIM3) is a member of the tripartite motif (TRIM) protein family and is reported to be involved in the pathogenesis of various cancers. The role of TRIM3 in hepatocellular carcinoma (HCC) is unknown; thus, the goal of this study was to explore the expression level and prognostic value of TRIM3 in HCC. The expression level of TRIM3 in HCC surgically resected tumors and corresponding nontumorous samples was detected by real-time quantitative RT-PCR, Western blotting, and immunohistochemistry. The correlation between TRIM3 expression level and the clinicopathological features and prognosis of HCC patients was also analyzed. We observed that TRIM3 expression was remarkably decreased in tumor tissue samples from HCC patients, relative to matched nontumorous tissue samples, at the mRNA (p = 0.018) and protein level (p = 0.02). Similarly, immunohistochemical analysis showed that 53.4 % of samples had low TRIM3 protein expression. Clinicopathological analysis revealed that low TRIM3 expression was significantly correlated with tumor size (p = 0.034), histological grade (p < 0.001), serum AFP (p = 0.025), and TNM stage (p = 0.021). Furthermore, Kaplan-Meier survival analysis revealed that low TRIM3 expression was associated with poor survival in HCC patients. Finally, our multivariate Cox regression analysis showed that TRIM3 expression was an independent prognostic factor for overall survival of HCC patients. In conclusion, this study suggests that TRIM3 may play a significant role in HCC progression and acts as a valuable prognostic marker and potential therapeutic target for HCC.
... Tumor protein D52 is a naturally expressed intracellular protein present at low but detectable levels in healthy cells and tissues where its normal function has yet to be defined. Increased expression of D52 has been demonstrated in association with prostate cancer as well as numerous other human malignancies678910111213141516171819202122. The murine orthologue of D52 (mD52) is ~ 86% identical to human D52 (hD52) at the amino acid level [23]. ...
Tumor protein D52 (D52) is expressed at low levels in normal cells, but over-expressed in prostate carcinomas and numerous other malignancies. Murine D52 (mD52) parallels the expression pattern of the human orthologue (hD52) and shares ~ 86% amino acid identity. Over-expression of mD52 in non-transformed murine fibroblasts induces anchorage independent growth and spontaneous metastasis. The TRAMP model was employed to study DNA-based D52 vaccines against prostate cancer. Immunizations consisted of mD52-DNA, hD52-DNA or a combination of both, followed by challenge with mD52 positive, TRAMP-C1 tumor cells. Greater protection (70%) was observed 10 months post challenge in mice immunized with hD52 DNA. Survivors of the initial tumor challenge rejected a second tumor challenge with mD52 positive, autochthonous TRAMP-C2 tumor cells given in the opposite flank more than four months after the first challenge. Analysis of the T cell function from survivors indicated that a Th1-type cellular immune response was involved in tumor rejection. A potentially unique subset of CD8+ IL-10+ T cells was also elicited and may play a role in inhibiting vaccine induced tumor immunity, suggesting that a deeper mechanistic understanding of these T cells in D52 vaccine-induced immunity may be important for developing a more potent cancer vaccine.
... Tumor protein D52 is a naturally expressed intracellular protein present at low but detectable levels in healthy cells and tissues where its normal function has yet to be defined. Increased expression of D52 has been demonstrated in association with prostate cancer as well as numerous other human malignancies678910111213141516171819202122. The murine orthologue of D52 (mD52) is ~ 86% identical to human D52 (hD52) at the amino acid level [23]. ...
Tumor protein D52 (D52) is expressed at low levels in normal cells, but
over-expressed in prostate carcinomas and numerous other malignancies.
Murine D52 (mD52) parallels the expression pattern of the human orthologue
(hD52) and shares ~ 86% amino acid identity. Over-expression of mD52 in nontransformed
murine fibroblasts induces anchorage independent growth and
spontaneous metastasis. The TRAMP model was employed to study DNA-based
D52 vaccines against prostate cancer. Immunizations consisted of mD52-DNA,
hD52-DNA or a combination of both, followed by challenge with mD52 positive,
TRAMP-C1 tumor cells. Greater protection (70%) was observed 10 months
post challenge in mice immunized with hD52 DNA. Survivors of the initial tumor
challenge rejected a second tumor challenge with mD52 positive, autochthonous
TRAMP-C2 tumor cells given in the opposite flank more than four months
after the first challenge. Analysis of the T cell function from survivors indicated
that a Th1-type cellular immune response was involved in tumor rejection. A
potentially unique subset of CD8+ IL-10+ T cells was also elicited and may play
a role in inhibiting vaccine induced tumor immunity, suggesting that a deeper
mechanistic understanding of these T cells in D52 vaccine-induced immunity
may be important for developing a more potent cancer vaccine.
Plants have a history of being employed in managing breast cancer. However, no scientific evidence supports the idea
that these plants can effectively reduce the level of HER2 expression. In this study, extracts from 10 medicinal plants were evaluated
for their anticancer properties against HER2-positive breast cancer cells through various methods, including the SRB assay, comet
assay, annexin V-FITC dual staining, and immunoblotting. All extracts exerted antiproliferative activity against HER2-positive breast
cancer cells. Furthermore, Terminalia chebula (T. chebula), Berberis aristata (B. aristata), and Mucuna pruriens (M. pruriens) reduced
HER2 expression in tested cell lines. In addition, an increased Bax/Bcl-2 ratio was observed after the treatment. A comparative
proteomics study showed modulation in the proteome profile of breast cancer cells after treatment with T. chebula, B. aristata, Punica
granatum, M. pruriens, and Acorus calamus. Metabolic profiling of lead plants revealed the existence of multiple anticancer
compounds. Our study demonstrates the considerable potential of the mentioned plants as innovative therapies for HER2-positive
breast cancer.
Toll-like receptor 4 (TLR4), a pattern recognition receptor, is activated by lipopolysaccharides (LPS) and induces the MyD88 pathway, which subsequently produces pro-inflammatory cytokines through activation of transcriptional nuclear factor (NF)-κB. Statins have been widely prescribed to reduce cholesterol synthesis for patients with cardiovascular disease. Statins may have pleiotropic effects, which include anti- and pro-inflammatory effects on cells. The molecular mechanism of the sequential influence of LPS and statin on the innate immune system remains unknown. We employed affinity purification-spacer-arm controlled cross-linking (AP-SPACC) MS-based proteomics analysis to identify the LPS- and statin-LPS-responsive proteins and their networks. LPS-stimulated RAW 264.7 macrophage cells singly and combined with the drug statin used in this study. Two chemical cross-linkers with different spacer chain lengths were utilized to stabilize the weak and transient interactors. Proteomic analysis identified 1631 differentially expressed proteins. We identified 151 immune-response proteins through functional enrichment analysis and visualized their interaction networks. Selected candidate protein-coding genes were validated, specifically squamous cell carcinoma antigens recognized by T cells 3, sphingosine-1-phosphate lyase 1, Ras-related protein Rab-35, and tumor protein D52 protein-coding genes through transcript-level expression analysis. The expressions of those genes were significantly increased upon statin treatment and decreased in LPS-stimulated macrophage cells. Therefore, we presumed that the expression changes of genes occurred due to immune response during activation of inflammation. These results highlight the immune-responsive proteins network, providing a new platform for novel investigations and discovering future therapeutic targets for inflammatory diseases.
Development of cancer vaccines targeting tumor self-antigens is complex and challenging due to the difficulty of overcoming immune tolerance to self-proteins. Vaccination against tumor self-protein D52 (D52) has been successful, although complete protection appears impaired by immune regulation. Our previous studies suggest that vaccine elicited CD8 + T cells producing interleukin 10 (IL-10) may have a negative impact on tumor protection. Understanding the role CD8+ IL-10 + T cells play in the immune response following vaccination with D52 could result in a more potent vaccine. To address this, we vaccinated IL-10 deficient mice with the murine orthologue of D52; vaccination of wild type (wt) C57BL/6J served as a control for comparison. In separate experiments, D52 vaccinated wt mice were administered IL-10R-specific mAb to neutralize IL-10 function. Interestingly, we observed similar protection against primary tumor challenge in the experimental groups compared to the controls. However, individual IL-10 deficient mice that rejected the primary tumor challenge were re-challenged 140 days post-primary challenge to access vaccine durability and immunologic memory against tumor recurrence. Mice deficient in IL-10 demonstrated a memory response in which 100% of the mice were protected from secondary tumor challenge, while wt mice had diminished recall response (25%) against tumor recurrence. These results with analysis of vaccine-elicited CD8 + T cells for tumor-specific killing and regulatory cell marker expression, add further support to our premise that CD8+ IL-10 + T cells elicited by D52 tumor-self protein vaccine contribute to the suppression of a memory CTL responses and durable tumor immunity.
Purpose:
An early and accurate diagnosis of ovarian carcinoma (OC) is likely to reduce morbidity and mortality of the patients. To improve the clinical outcome in OC patients, present study is aimed to identify robust biomarkers for early OC diagnosis and prognosis.
Experimental design:
In order to look for early-stage protein markers, a systematic protein profiling approach involving 2-dimensional gel electrophoresis coupled with MALDI-TOF MS analyses of human malignant and non-malignant ovarian biopsy samples and analysis of the data by using relevant software was performed in this study.
Results:
Six 2D-gel spots, corresponding to five proteins, displayed statistically significant differential expression in the tumor tissues in comparison with the non-malignant tissues [FDR ≤0.05; PMF score ≥79]. In silico pathway studies by IPA predicted two proteins i.e., Ca2+ dependent membrane-binding protein annexin A6 (AnxA6) and the metabolic enzyme L-lactate dehydrogenase A chain, as potential predictive biomarkers. Increased expression of AnxA6 was further ascertained by Western blot and ELISA analysis in the resected tissues and the plasma of the subjects. The expression was found markedly increased particularly in the advanced stage tumors.
Conclusions and clinical relevance:
The significant up-regulation of AnxA6 in OC, reported for the first time, is likely to provide insight into the mechanism of OC progression, which may lead to the design of potential diagnostic and therapeutic strategies. This article is protected by copyright. All rights reserved.
Background: Androgen steroid hormones are key drivers of prostate cancer. Previous work has shown that androgens can drive the expression of alternative mRNA isoforms as well as transcriptional changes in prostate cancer cells. Yet to what extent androgens control alternative mRNA isoforms and how these are expressed and differentially regulated in prostate tumours is unknown.
Methods: Here we have used RNA-Seq data to globally identify alternative mRNA isoform expression under androgen control in prostate cancer cells, and profiled the expression of these mRNA isoforms in clinical tissue.
Results: Our data indicate androgens primarily switch mRNA isoforms through alternative promoter selection. We detected 73 androgen regulated alternative transcription events, including utilisation of 56 androgen-dependent alternative promoters, 13 androgen-regulated alternative splicing events, and selection of 4 androgen-regulated alternative 3′ mRNA ends. 64 of these events are novel to this study, and 26 involve previously unannotated isoforms. We validated androgen dependent regulation of 17 alternative isoforms by quantitative PCR in an independent sample set. Some of the identified mRNA isoforms are in genes already implicated in prostate cancer (including LIG4 , FDFT1 and RELAXIN ), or in genes important in other cancers (e.g. NUP93 and MAT2A ). Importantly, analysis of transcriptome data from 497 tumour samples in the TGCA prostate adenocarcinoma (PRAD) cohort identified 13 mRNA isoforms (including TPD52 , TACC2 and NDUFV3 ) that are differentially regulated in localised prostate cancer relative to normal tissue, and 3 ( OSBPL1A , CLK3 and TSC22D3 ) which change significantly with Gleason grade and tumour stage.
Conclusions: Our findings dramatically increase the number of known androgen regulated isoforms in prostate cancer, and indicate a highly complex response to androgens in prostate cancer cells that could be clinically important.
Background:
Radioresistance is a challenge in the treatment of cervical cancer. Recent studies have reported that microRNAs (miRNAs) mediate radiotherapy resistance and play a vital role in the occurrence and development of cancer. The aim of this study was to investigate whether the expression of miR-15a-3p was correlated with radiosensitivity in cervical cancer.
Methods:
Quantitative real-time PCR experiment was performed to detect the expression of miR-15a-3p in cervical cancer tissues and cells lines. Then, the effect of miR-15a-3p on proliferation in cervical cancer cells radiation-induced were determined by using CCK-8, clonogenic formation and EdU assays. In addition, the TUNEL, flow cytometry analysis and western blotting assays were conducted to evaluate radiation-induced cells apoptosis. A dual-luciferase reporter assay was used to test the target. In addition, tumor xenograft experiment was conducted to test tumor growth in vivo.
Results:
In this study, miR-15a-3p was downregulated in cervical cancer tissues and cells lines, however, the expression of miR-15a-3p significantly increased exposed to radiation. Moreover, over-expression of miR-15a-3p inhibited cells proliferation and enhanced cells apoptosis radiation-induced. Further, TPD52 was identified as a direct target of miR-15a-3p. Inhibition of TPD52 could suppress cells proliferation and induce cells apoptosis. Tumor xenograft experiments indicated that over-expression of miR-15a-3p could increase sensitivity to radiation therapy by targeting TPD52.
Conclusion:
In conclusion, our findings suggested that miR-15a-3p enhanced radiosensitivity in cervical cancer by targeting tumor protein D52, suggesting that miR-15a-3p may be a potential therapeutic target for cervical cancer patients.
Polycyclic aromatic hydrocarbons (PAHs) comprise an important class of environmental pollutants that are known to cause lung cancer in animals and are suspected lung carcinogens in humans. Moreover, evidence from cell-based studies points to PAHs as modulators of the epigenome. The objective of this work was to assess patterns of genome-wide DNA methylation in lung tissues of adult offspring initiated in utero with the transplacental PAH carcinogens dibenzo [def,p]chrysene (DBC) or benzo [a]pyrene (BaP). Genome-wide methylation patterns for normal (not exposed), normal adjacent and lung tumor tissues obtained from adult offspring were determined using methylated DNA immunoprecipitation (MeDIP) with the NimbleGen mouse DNA methylation CpG island array. Lung tumor incidence in 45-week old mice initiated with BaP was 32%, much lower than that of the DBC-exposed offspring at 96%. Also, male offspring appeared more susceptible to BaP as compared to females. Distinct patterns of DNA methylation were associated with non-exposed, normal adjacent and adenocarcinoma lung tissues, as determined by principal components, hierarchical clustering and gene ontology analyses. From these methylation profiles, a set of genes of interest was identified that includes potential important targets for epigenetic modification during the process of lung tumorigenesis in animals exposed to environmental PAHs.
Tumor protein D52 (TPD52), a proto-oncogene is overexpressed in a variety of epithelial carcinomas and plays an important role in cell proliferation, migration and cell death. In the present study we found that the treatment of IMR-32 neuroblastoma (NB) cells with retinoic acid (RA) stimulates an increase in expression of TPD52. TPD52 expression is detectable after 72 h, can be maintained till differentiation of NB cells suggesting that TPD52 is involved in differentiation. Here, we demonstrate that TPD52 is essential for RA to promote differentiation of NB cells. Our results show that exogenous expression of EGFP-TPD52 in IMR-32 cells resulted cell differentiation even without RA. RA by itself and with overexpression of TPD52 can increase the ability of NB cells differentiation. Interestingly, transfection of IMR-32 cells with a specific small hairpin RNA for efficient knockdown of TPD52 attenuated RA induced NB cells differentiation. Transcriptional and translational level expression of neurotropic (BDNF, NGF, Nestin) and differentiation (β III tubulin, NSE, TH) factors in NB cells with altered TPD52 expression and/or RA treatment confirmed essential function of TPD52 in cellular differentiation. Furthermore, we show that TPD52 protects cells from apoptosis and arrest cell proliferation by varying expression of p27Kip1, activation of Akt and ERK1/2 thus promoting cell differentiation. Additionally, inhibition of STAT3 activation by its specific inhibitor arrested NB cells differentiation by EGFP-TPD52 overexpression with or without RA. Taken together, our data reveal that TPD52 act through activation of JAK/STAT signaling pathway to undertake NB cells differentiation induced by RA. This article is protected by copyright. All rights reserved.
Although tumor protein D52 (TPD) family proteins were first identified nearly 20 years ago, their molecular regulatory mechanisms remain unclear. Therefore, we investigated the post-transcriptional regulation of TPD52 family genes. An RNA immunoprecipitation assay showed the potential binding ability of TPD52 family mRNAs to several RNA-binding proteins, and an RNA degradation assay revealed that TPD52 is subject to more prominent post-transcriptional regulation than TPD53 and 54. We subsequently focused on the 3'-untranslated region (3'-UTR) of TPD52 as a cis -acting element in post-transcriptional gene regulation. Several deletion mutants of the 3'-UTR of TPD52 mRNA were constructed and ligated to the 3' end of a reporter green fluorescence protein gene. RNA degradation assay revealed that a minimal cis -acting region, located in the 78-280 region of the 5'-proximal region of the 3'-UTR, stabilized the reporter mRNA. Biotin pull-down and RNA immunoprecipitation assays revealed specific binding of the region to T-cell intracellular antigen 1 (TIA-1) and TIA-1-related protein (TIAR). Knockdown of TIA-1/TIAR decreased not only the expression, but also the stability of TPD52 mRNA; it also decreased the expression and stability of the reporter gene ligated to the 3' end of the 78-280 fragment. Stimulation of TGF-b and EGF decreased the binding ability of these factors, resulted in decreased mRNA stability. These results indicate that the 78-280 fragment and TIA-1/TIAR concordantly contribute to mRNA stability as a cis -acting element and trans -acting factor(s), respectively. Thus, we herein report the specific interactions between these elements in the post-transcriptional regulation of the TPD52 gene.
Tumor protein D52 (TPD52) is a member of the TPD52-like protein family and plays different roles in various types of malignancies. However, its role in renal cell carcinoma (RCC) is still unclear. In this study, we investigated role of TPD52 in RCC. The mechanism of TPD52 in RCC was also investigated. Our data demonstrated that the expression levels of TPD52 at both mRNA and protein were significantly decreased in RCC cells. Overexpression of TPD52 inhibited the proliferation, migration/invasion with decreased the epithelial-mesenchymal transition (EMT) phenotype in RCC cells, as well as attenuated the tumor growth in renal cancer xenografts. Mechanistically, overexpression of TPD52 inhibited significantly down-regulated the phosphorylation levels of PI3K and Akt in RCC cells. In conclusion, the present study demonstrated that TPD52 inhibited growth and metastasis of RCC, at least in part, through suppressing the PI3K/Akt signaling pathway. Therefore, these findings suggest that TPD52 may be a promising therapeutic target for the treatment of human RCC.
Our study aimed to investigate whether MicroRNA-449 (miR-449) plays a key role in regulating the migration and invasionof breast cancer cells via targeting Tumor Protein D52 (TPD52). The results of qRT-PCR and western blotting showed that, in comparison with normal breast tissues and cells, miR-449 was significantly downregulated in breast cancer tissues and cells, while TPD52 was markedly upregulated. After transfection with an miR-449 inhibitor, suppression of miR-449 significantly promoted cell migration and invasion. Also, when miR-449 was overexpressed by transfection with miR-449 mimics, E-cadherin expression significantly increased and the expression of N-cadherin and vimentin were markedly decreased, whereas the opposite effects were obtained when miR-449 was suppressed by transfection with an miR-449 inhibitor. TPD52 was also confirmed as the direct target of miR-449 via luciferase reporter analysis. Knockdown of TPD52 significantly alleviated the effects of miR-449 overexpression on cell migration and invasion, as well as the expression of E-cadherin, N-cadherin, and vimentin. Our results indicate that downregulation of miR-449 may promote the migration and invasion of breast cancer cells by targeting TPD52. miR-449 may serve as a potential target in the therapy of breast cancer.
Developmental exposure to endocrine-disrupting chemicals (EDCs), 17β-estradiol-3-benzoate (EB) and bisphenol A (BPA), increases susceptibility to prostate cancer (PCa) in rodent models. Here, we used the methylated-CpG island recovery assay (MIRA)-assisted genomic tiling and CpG island arrays to identify treatment-associated methylome changes in the postnatal day (PND)90 dorsal prostate tissues of Sprague-Dawley rats neonatally (PND1, 3, and 5) treated with 25 µg/pup or 2,500 µg EB/kg body weight (BW) or 0.1 µg/pup or 10 µg BPA/kg BW. We identified 111 EB-associated and 86 BPA-associated genes, with 20 in common, that have significant differentially methylated regions (DMRs). Pathway analysis revealed cancer as the top common disease pathway. Bisulfite sequencing validated the differential methylation patterns observed by array analysis in 15 identified candidate genes. The methylation status of seven (Pitx3, Wnt10b, Paqr4, Sox2, Chst14, Tpd52, Creb3l4) of these 15 genes exhibited an inverse correlation with gene expression in tissue samples. Cell-based assays, using 5-aza-cytidine-treated normal (NbE-1) and cancerous (AIT) rat prostate cells, added evidence of DNA methylation-mediated gene expression of six genes (exception: Paqr4). Functional connectivity of these genes was linked to embryonic stem cell pluripotency. Furthermore, clustering analyses using the dataset from The Cancer Genome Atlas (TCGA) revealed that expression of this set of seven genes was associated with recurrence-free survival of PCa patients. In conclusion, our study reveals that gene-specific promoter methylation changes, resulting from early-life EDC exposure in the rat, may serve as predictive epigenetic biomarkers of PCa recurrence, and raises the possibility that such exposure may impact the human disease.
In this work, we combined a newly developed matrix coating technique -- matrix coating assisted by an electric field (MCAEF) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to enhance the imaging of peptides and proteins in tissue specimens of human prostate cancer. MCAEF increased the signal-to-noise ratios of the detected proteins by a factor of 2 to 5 and 232 signals were detected within the m/z 3500-37500 mass range on a time-of-flight mass spectrometer and with the sinapinic acid MALDI matrix. Among these species, 3 proteins (S100-A9, S100-A10 and S100-A12) were only observed in the cancerous cell region and 14 proteins, including a fragment of mitogenactivated protein kinase/extracellular signal-regulated kinase kinase kinase 2, a fragment of cAMPregulated phosphoprotein 19, 3 apolipoproteins (C-I, A-I, and A-II), 2 S100 proteins (A6 and A8), β-microseminoprotein, tumor protein D52, α-1-acid glycoprotein 1, heat shock protein β-1, prostate-specific antigen, and 2 unidentified large peptides at m/z 5002.2 and 6704.2, showed significantly differential distributions at the p<0.05 (t-test) level between the cancerous and the non-cancerous regions of the tissue. Among these 17 species, the distributions of apolipoprotein C-I, S100-A6, and S100-A8 were verified by immunohistological staining. In summary, this study resulted in the imaging of the largest group of proteins in prostate cancer tissues by MALDI-MS reported thus far, and is the first to show a correlation between S100 proteins and prostate cancer in a MS imaging study. The successful imaging of the three proteins only found in the cancerous tissues, as well as those showing differential expressions demonstrated the potential of MCAEF-MALDI/MS for the in situ detection of potential cancer biomarkers.
Prostate cancer (PCa) is the most common epithelial cancer and second leading cause of cancer death among men in the US. Prostate cancer tumorigenesis is associated with numerous molecular events including transcriptomic, epigenetic, and copy number alterations. In this thesis, we characterized two major types of genome-wide events to understand their global implications and contributions in PCa.
First, we assessed genome-wide copy number variations (CNVs) using array comparative genomic hybridization of laser-capture microdissected prostate cancer samples representing multiple stages of PCa progression. Minimal common regions (MCR) of CNVs, including novel regions, were defined for each sample type. Integrative analysis of MCRs with matched gene expression profiles revealed genes with coordinated CNV and altered transcript expression during PCa progression. We also identified MCRs that distinguished PCa samples harboring or lacking an ETS gene fusion.
Secondly, we characterized genome-wide DNA methylation patterns, an epigenetic mark known to repress gene transcription. We employed a novel technology termed Methylplex-Next Generation Sequencing (M-NGS) which uses methylation sensitive restriction enzymes to enrich methylated genomic regions. The performance of M-NGS to characterize global methylation was tested in LNCaP prostate cancer and PrEC benign prostate epithelial cells. Multiple techniques, including bisulfite sequencing, validated the results. Detailed analyses revealed diverse promoter methylation patterns which correlated with transcriptional repression. Interestingly, integration of DNA methylation and H3K4me3 ChIP-Seq data in LNCaP identified differential epigenetic regulation of specific transcript isoforms.
We next employed M-NGS to characterize PCa tissue samples. We identified 2,481 cancer-specific methylated regions, including WFDC2 promoter methylation, which served as a PCa biomarker and was validated on an independent tissue cohort. Finally we used a 3-way integrative analysis of these genome-wide events and identified regions with co-occurrence of copy number gain/loss and DNA methylation, associated with aberrant gene expression in PCa.
In summary, this thesis work presents a comprehensive analyses of genome-wide copy number and methylation changes and its global implications on transcriptional regulation for the first time in prostate cancer. The datasets generated here will be a valuable public resource for genome-wide analysis in the future.
TPD52L2 (tumor protein D52-like 2) is a member of TPD52 family which has been implicated in multiple human cancers. Recently, TPD52 protein was shown to be associated with several malignancies, but very little is known about the function of TPD52L2 in cancers, especially in glioma to date, and its roles in glioma occurrence and progression remain to be elucidated. In the present study, we employed lentivirus—mediated RNA interference (RNAi) to knock down TPD52L2 expression in human glioma cell line U251. We found that knockdown of TPD52L2 significantly not only inhibited cell proliferation and colony formation, but also induced G0/G1 cell cycle arrest in vitro. Taken together, these findings suggest that TPD52L2 might play an important role in glioma tumorigenesis.
We describe a differential screening method for cDNA libraries which used a combination of subtracted and PCR-amplified cDNA probes, and which can be applied to the selection of genes expressed in multiple tissues. This technique was used to identify genes commonly overexpressed in breast and basal cell carcinomas. These represent stromally dependent, invasive tumors with and without metastatic capacity. Thus, this screening sought to identify genes involved in the early stages of tumor progression. We identified a total of 16 genes, including c-erbB-2 and tissue inhibitor of metalloproteinases 3 whose products have been implicated in tumorigenesis or invasion. We also identified a novel sequence (D52) showing little homology with others described in any species, which maps to the human chromosomal band 8q21. In situ RNA hybridizations of breast carcinoma sections indicated that the D52 gene was expressed in cancer cells, whereas other genes identified in the differential screening were expressed in fibroblastic or inflammatory cells within the tumor stroma. Thus, the procedure developed in this study selected genes expressed in a diversity of cell types, indicating its potential usefulness in other systems.
We examined the idea that aspartate metabolism by Lactobacillus subsp. M3 is organized as a proton-motive metabolic cycle by using reconstitution to monitor the activity of the carrier, termed AspT, expected to carry out the electrogenic exchange of precursor (aspartate) and product (alanine). Membranes of Lactobacillus subsp. M3 were extracted with 1.25% octyl glucoside in the presence of 0. 4% Escherichia coli phospholipid and 20% glycerol. The extracts were then used to prepare proteoliposomes loaded with either aspartate or alanine. Aspartate-loaded proteoliposomes accumulated external [3H]aspartate by exchange with internal substrate; this homologous self-exchange (Kt = 0.4 mm) was insensitive to potassium or proton ionophores and was unaffected by the presence or absence of Na+, K+, or Mg2+. Alanine-loaded proteoliposomes also took up [3H]aspartate in a heterologous antiport reaction that was stimulated or inhibited by an inside-positive or inside-negative membrane potential, respectively. Several lines of evidence suggest that these homologous and heterologous exchange reactions were catalyzed by the same functional unit. Thus, [3H]aspartate taken up by AspT during self-exchange was released by a delayed addition of alanine. In addition, the spontaneous loss of AspT activity that occurs when a detergent extract is held at 37 degrees C prior to reconstitution was prevented by the presence of either aspartate (KD(aspartate) = 0.3 mm) or alanine (KD(alanine) > or = 10 mm), indicating that both substrates interact directly with AspT. These findings are consistent with operation of a proton-motive metabolic cycle during aspartate metabolism by Lactobacillus subsp. M3.
We reported previously that post-mitotic chicken embryonic neuroretina (NR) cells are induced to proliferate following in vitro infection with RAV-1, a retrovirus that does not carry an oncogene. NR cell multiplication results from the frequent activation and subsequent retroviral transduction of two related serine/threonine protein kinases, the c-mil/c-raf or c-Rmil/B-raf genes. We also showed that a very early event in the activation of these proto-oncogenes is the synthesis of chimeric mRNAs containing viral and cellular sequences joined by a splicing mechanism. In the current study, we have examined the ability of RAV-1 to induce proliferation of quail NR cells. By using the reverse transcription-polymerase chain reaction technique, we identified, in several proliferating quail NR cultures infected with RAV-1, a chimeric mRNA containing cellular sequences joined to the RAV-1 splice donor site. These cellular sequences are derived from a gene designated R10, which is expressed through a 1.9-kilobase (kb) mRNA detected in several embryonic tissues. A second transcript of 2.3 kb is specifically expressed in the NR, where both transcripts are developmentally regulated. The R10 cDNA encodes a 251-amino acid polypeptide that contains a leucine zipper motif. It exhibits significant similarity with the putative D52/N8L protein, encoded by an mRNA reported previously to be overexpressed in human breast and lung carcinomas. By using polyclonal antibodies specific for its amino-terminal and leucine zipper-containing regions, we identified the R10 gene product as a cytoplasmic protein of 23 kDa in cultured avian fibroblasts. A second protein of 30 kDa is detected in post-mitotic NR cells that express the 2.3-kb transcript. We also show, by in vitro transcription/translation and immunoprecipitation, that the R10 protein can readily form homodimers, presumably through its leucine zipper motif.
Comparative genomic hybridization was applied to detect and map changes in DNA copy number in 24 well or moderately differentiated epithelial ovarian carcinomas (eight serous, eight mucinous and eight endometrioid carcinomas). Twenty-three of the 24 tumours showed changes in DNA copy number in one or several regions (median 4, range 1-17). Gains were more frequent than losses (ratio 1.6:1.0). The most frequent gains occurred in chromosomes 1q (38%), 2p (29%), 7q (25%), 8q(38%) and 17q (38%), and the most common losses were located in chromosomes 8p (21%), 9p (25%) and 13q (21%). High-level amplifications were detected in seven tumours at 1q22-32, 2p15-22, 3qcen-23, 6p21-22 and 8q. In the three histological subtypes the copy number karyotypes showed substantial differences. Gains at 1q were observed in endometrioid (five cases) and serous tumours (four cases). Increased copy number at 10q was seen in endometrioid tumours only (four cases), whereas gains at 11q occurred mostly in serous tumours (four cases). In mucinous tumours, the most common copy number change was a gain at 17q (six cases). The results show that, in epithelial ovarian carcinoma, changes in DNA copy number are a rule rather than an exception, chromosomes 1, 2, 7, 8, 9, 13 and 17 being the most frequently affected. The diverging pattern of genetic changes seen in epithelial ovarian carcinomas with different histological phenotypes suggests that various pathways may lead to tumorigenesis and/or progression in these subgroups.
In the United States, ovarian cancer is the fourth most common cause of cancer-related deaths among women. The most important prognostic factor for this cancer is tumor stage, or extent of disease at diagnosis. Although women with low-stage tumors have a relatively good prognosis, most women diagnosed with late-stage disease eventually succumb to their cancer. In an attempt to understand early events in ovarian carcinogenesis, and to explore steps in its progression, we have applied multiple molecular genetic techniques to the analysis of 21 early-stage (stage I/II) and 17 advanced-stage (stage III/IV) ovarian tumors. These techniques included expression profiling with cDNA microarrays containing approximately 18,000 expressed sequences, and comparative genomic hybridization to address the chromosomal locations of copy number gains as well as losses. Results from the analysis indicate that early-stage ovarian cancers exhibit profound alterations in gene expression, many of which are similar to those identified in late-stage tumors. However, differences observed at the genomic level suggest differences between the early- and late-stage tumors and provide support for a progression model for ovarian cancer development.
Cell lines derived from human tumors have historically served as the primary experimental model system for exploration of tumor cell biology and pharmacology. Cell line studies, however, must be interpreted in the context of artifacts introduced by selection and establishment of cell lines in vitro. This complication has led to difficulty in the extrapolation of biology observed in cell lines to tumor biology in vivo. Modern genomic analysis tool like DNA microarrays and gene expression profiling now provide a platform for the systematic characterization and classification of both cell lines and tumor samples. Studies using clinical samples have begun to identify classes of tumors that appear both biologically and clinically unique as inferred from their distinctive patterns of expressed genes. In this review, we explore the relationships between patterns of gene expression in breast tumor derived cell lines to those from clinical tumor specimens. This analysis demonstrates that cell lines and tumor samples have distinctive gene expression patterns in common and underscores the need for careful assessment of the appropriateness of any given cell line as a model for a given tumor subtype.
Tissue microarray technology is a new method used to analyze several hundred tumor samples on a single slide allowing high throughput analysis of genes and proteins on a large cohort. The original methodology involves coring tissues from paraffin-embedded tissue donor blocks and placing them into a single paraffin block. One difficulty with paraffin-embedded tissue relates to antigenic changes in proteins and mRNA degradation induced by the fixation and embedding process. We have modified this technology by using frozen tissues embedded in OCT compound as donor samples and arraying the specimens into a recipient OCT block. Tumor tissue is not fixed before embedding, and sections from the array are evaluated without fixation or postfixed according to the appropriate methodology used to analyze a specific gene at the DNA, RNA, and/or protein levels. While paraffin tissue arrays can be problematic for immunohistochemistry and for RNA in situ hybridization analyses, this method allows optimal evaluation by each technique and uniform fixation across the array panel. We show OCT arrays work well for DNA, RNA, and protein analyses, and may have significant advantages over the original technology for the assessment of some genes and proteins by improving both qualitative and quantitative results.
Analysis of ovarian carcinomas has shown that karyotypes are often highly abnormal and cannot be identified with certainty by conventional cytogenetic methods. In this study, 17 tumors derived from 13 patients were analyzed by a combination of spectral karyotyping (SKY), comparative genomic hybridization (CGH), and expression microarrays. Within the study group, a total of 396 chromosomal rearrangements could be identified by SKY and CGH analysis. When the distribution of aberrations was normalized with respect to relative genomic length, chromosomes 3, 8, 11, 17, and 21 had the highest frequencies. Parallel microarray expression studies of 1718 human cDNAs were used to analyze expression profiles and to determine whether correlating gene expression with chromosomal rearrangement would identify smaller subsets of differentially expressed genes. Within the entire set of samples, microarray expression analysis grouped together poorly differentiated tumors irrespective of histological subtype. For three patients, a comparison between genomic alterations and gene expression pattern was performed on samples of primary and metastatic tumors. Their common origin was demonstrated by the close relationship of both the SKY and CGH karyotypes and the observed profiles of gene expression. In agreement with the pattern of genomic imbalance observed for chromosome 3 in ovarian cancer, the relative expression profile with respect to a normal ovary exhibited a contiguous pattern of reduced expression of genes mapping to the 3p25.5-3p21.31 and increased expression of genes from 3q13.33-3q28. This study demonstrates that SKY, CGH, and microarray analysis can in combination identify significantly smaller subsets of differentially expressed genes for future studies.
The increasing availability and maturity of DNA microarray technology has led to an explosion of cancer profiling studies. To extract maximum value from the accumulating mass of publicly available cancer gene expression data, methods are needed to evaluate, integrate, and intervalidate multiple datasets. Here we demonstrate a statistical model for performing meta-analysis of independent microarray datasets. Implementation of this model revealed that four prostate cancer gene expression datasets shared significantly similar results, independent of the method and technology used (i.e., spotted cDNA versus oligonucleotide). This interstudy cross-validation approach generated a cohort of genes that were consistently and significantly dysregulated in prostate cancer. Bioinformatic investigation of these genes revealed a synchronous network of transcriptional regulation in the polyamine and purine biosynthesis pathways. Beyond the specific implications for prostate cancer, this work establishes a much-needed model for the evaluation, cross-validation, and comparison of multiple cancer profiling studies.
The human prostate gland is an important target organ of androgenic hormones. Testosterone and dihydrotestosterone interact with the androgen receptor to regulate vital aspects of prostate growth and function including cellular proliferation, differentiation, apoptosis, metabolism, and secretory activity. Our objective in this study was to characterize the temporal program of transcription that reflects the cellular response to androgens and to identify specific androgen-regulated genes (ARGs) or gene networks that participate in these responses. We used cDNA microarrays representing about 20,000 distinct human genes to profile androgen-responsive transcripts in the LNCaP adenocarcinoma cell line and identified 146 genes with transcript alterations more than 3-fold. Of these, 103 encode proteins with described functional roles, and 43 represent transcripts that have yet to be characterized. Temporal gene expression profiles grouped the ARGs into four distinct cohorts. Five uncharacterized ARGs demonstrated exclusive or high expression levels in the prostate relative to other tissues studied. A search of available DNA sequence upstream of 28 ARGs identified 25 with homology to the androgen response-element consensus-binding motif. These results identify previously uncharacterized and unsuspected genes whose expression levels are directly or indirectly regulated by androgens; further, they provide a comprehensive temporal view of the transcriptional program of human androgen-responsive cells.
Androgens are required for both normal prostate development and prostate carcinogenesis. We used DNA microarrays, representing approximately 18,000 genes, to examine the temporal program of gene expression following treatment of the human prostate cancer cell line LNCaP with a synthetic androgen.
We observed statistically significant changes in levels of transcripts of more than 500 genes. Many of these genes were previously reported androgen targets, but most were not previously known to be regulated by androgens. The androgen-induced expression programs in three additional androgen-responsive human prostate cancer cell lines, and in four androgen-independent subclones derived from LNCaP, shared many features with those observed in LNCaP, but some differences were observed. A remarkable fraction of the genes induced by androgen appeared to be related to production of seminal fluid and these genes included many with roles in protein folding, trafficking, and secretion.
Prostate cancer cell lines retain features of androgen responsiveness that reflect normal prostatic physiology. These results provide a broad view of the effect of androgen signaling on the transcriptional program in these cancer cells, and a foundation for further studies of androgen action.
Genomic DNA copy number alterations are key genetic events in the development and progression of human cancers. Here we report a genome-wide microarray comparative genomic hybridization (array CGH) analysis of DNA copy number variation in a series of primary human breast tumors. We have profiled DNA copy number alteration across 6,691 mapped human genes, in 44 predominantly advanced, primary breast tumors and 10 breast cancer cell lines. While the overall patterns of DNA amplification and deletion corroborate previous cytogenetic studies, the high-resolution (gene-by-gene) mapping of amplicon boundaries and the quantitative analysis of amplicon shape provide significant improvement in the localization of candidate oncogenes. Parallel microarray measurements of mRNA levels reveal the remarkable degree to which variation in gene copy number contributes to variation in gene expression in tumor cells. Specifically, we find that 62% of highly amplified genes show moderately or highly elevated expression, that DNA copy number influences gene expression across a wide range of DNA copy number alterations (deletion, low-, mid- and high-level amplification), that on average, a 2-fold change in DNA copy number is associated with a corresponding 1.5-fold change in mRNA levels, and that overall, at least 12% of all the variation in gene expression among the breast tumors is directly attributable to underlying variation in gene copy number. These findings provide evidence that widespread DNA copy number alteration can lead directly to global deregulation of gene expression, which may contribute to the development or progression of cancer.
We used a classical rodent model of transformation to understand the transcriptional processes, and hence the molecular and cellular events a given cell undergoes when progressing from a normal to a transformed phenotype. Src activation is evident in 80% of human colon cancer, yet the myriad of cellular processes effected at the level of gene expression has yet to be fully documented. We identified a Src 'transformation fingerprint' within the gene expression profiles of Src-transformed rat 3Y1 fibroblasts demonstrating a progression in transformation characteristics. To evaluate the role of this gene set in human cancer development and progression, we extracted the orthologous genes present on the Affymetrix Hu95A GeneChip (12k named genes) and compared expression profiles between the Src-induced rodent cell line model of transformation and staged colon tumors where Src is known to be activated. A similar gene expression pattern between the cell line model and staged colon tumors for components of the cell cycle, cytoskeletal associated proteins, transcription factors and lysosomal proteins suggests the need for co-regulation of several cellular processes in the progression of cancer. Genes not previously implicated in tumorigenesis were detected, as well as a set of 14 novel, highly conserved genes with here-to-fore unknown function. These studies define a set of transformation associated genes whose up-regulation has implications for understanding Src mediated transformation and strengthens the role of Src in the development and progression of human colon cancer. Supportive Supplemental Data can be viewed at http://pga.tigr.org/PGApubs.shtml.
The ability of the immune system to recognize structurally altered, amplified or aberrantly expressed proteins can be used to identify molecules of etiologic relevance to cancer and to define targets for cancer immunotherapy. In the current study, ninety-four distinct antigens reactive with serum IgG from breast cancer patients were identified by immunoscreening breast cancer-derived cDNA expression libraries (SEREX). A serological profile was generated for each antigen on the basis of reactivity with allogeneic sera from normal individuals and cancer patients, and mRNA expression profiles for coding sequences were assembled based upon the tissue distribution of expressed sequence tags, Northern blots and real-time RT-PCR. Forty antigens reacted exclusively with sera from cancer patients. These included well-characterized tumor antigens, e.g. MAGE-3, MAGE-6, NY-ESO-1, Her2neu and p53, as well as newly-defined breast cancer antigens, e.g. kinesin 2, TATA element modulatory factor 1, tumor protein D52 and MAGE D, and novel gene products, e.g. NY-BR-62, NY-BR-75, NY-BR-85, and NY-BR-96. With regard to expression profiles, two of the novel gene products, NY-BR-62 and NY-BR-85, were characterized by a high level of testicular mRNA expression, and were overexpressed in 60% and 90% of breast cancers, respectively. In addition, mRNA encoding tumor protein D52 was overexpressed in 60% of breast cancer specimens, while transcripts encoding SNT-1 signal adaptor protein were downregulated in 70% of these cases. This study adds to the growing list of breast cancer antigens defined by SEREX and to the ultimate objective of identifying the complete repertoire of immunogenic gene products in human cancer (the cancer immunome).
Drosophila melanogaster is a proven model system for many aspects of human biology. Here we present a two-hybrid–based protein-interaction map of
the fly proteome. A total of 10,623 predicted transcripts were isolated and screened against standard and normalized complementary
DNA libraries to produce a draft map of 7048 proteins and 20,405 interactions. A computational method of rating two-hybrid
interaction confidence was developed to refine this draft map to a higher confidence map of 4679 proteins and 4780 interactions.
Statistical modeling of the network showed two levels of organization: a short-range organization, presumably corresponding
to multiprotein complexes, and a more global organization, presumably corresponding to intercomplex connections. The network
recapitulated known pathways, extended pathways, and uncovered previously unknown pathway components. This map serves as a
starting point for a systems biology modeling of multicellular organisms, including humans.
A variety of proteins involved in gene expression have been localized within mammalian cell nuclei in a speckled distribution that predominantly corresponds to interchromatin granule clusters (IGCs). We have applied a mass spectrometry strategy to identify the protein composition of this nuclear organelle purified from mouse liver nuclei. Using this approach, we have identified 146 proteins, many of which had already been shown to be localized to IGCs, or their functions are common to other already identified IGC proteins. In addition, we identified 32 proteins for which only sequence information is available and thus these represent novel IGC protein candidates. We find that 54% of the identified IGC proteins have known functions in pre-mRNA splicing. In combination with proteins involved in other steps of pre-mRNA processing, 81% of the identified IGC proteins are associated with RNA metabolism. In addition, proteins involved in transcription, as well as several other cellular functions, have been identified in the IGC fraction. However, the predominance of pre-mRNA processing factors supports the proposed role of IGCs as assembly, modification, and/or storage sites for proteins involved in pre-mRNA processing.
Ovarian carcinoma has the highest mortality of all of the gynecologic cancers. The chromosomal changes in this tumor type are highly complex, and the karyotypes typically show severe aneuploidy. Despite the abundance of cytogenetic information, with approximately 400 published karyotypes, very little is known about the mode of karyotypic evolution and the possible presence of cytogenetic pathways related to tumor development. In the present investigation we used 387 ovarian carcinoma karyotypes to identify the most frequent genomic imbalances. Tumor cases were then classified with respect to the presence or absence of these imbalances and statistically analyzed to assess the order of appearance of chromosomal imbalances, as well as possible karyotypic pathways and cytogenetic subtypes. We establish the temporal order by which the different imbalances occur and show that at least two cytogenetic pathways exist, one characterized by +7, +8q, and +12, and one by 6q- and 1q-. We show that ovarian carcinomas develop through at least three phases of karyotypic evolution. At the early stages, Phase I, the karyotypic evolution seems to proceed though step-wise acquisition of changes. The transition to Phase II showed signs of an increased chromosomal instability, most probably caused by extensive telomere crisis and the onset of breakage-fusion-bridge cycles. This process was linked to the presence of imbalances characteristic for the 6q-/1q- pathway. The transition to Phase III involved triploidization and was also linked to the presence of the 6q-/1q- pathway.
We report a previously unrecognized prostate-specific protein, PrLZ (prostate leucine zipper), a new member of the Tumor Protein D52 (TPD52) family. The gene for PrLZ was localized at chromosome 8q21.1, a locus most frequently amplified in human prostate cancer. Multiple tissue analyses demonstrated PrLZ predominantly in the prostate gland. Although its expression was enhanced by androgens in androgen receptor-expressing cells, PrLZ was detected in all of the human prostate cancer cell lines, regardless of androgen receptor status. Monoclonal anti-PrLZ antibodies were produced and intense immunohistochemical staining of PrLZ was observed in prostate epithelial cells in intraepithelial neoplasia and prostate cancer, whereas lower-level staining was detected in normal and benign epithelial components of the prostate gland. As the only prostate-specific gene identified in the most frequently amplified genomic region in prostate cancer, PrLZ may be the link between chromosome 8q amplification and malignant transformation of the prostate epithelia.
It is unclear whether ovarian borderline tumors (tumors of low malignant potential) are independent entities or whether they are part of a continuum of tumor progression that culminates in ovarian carcinoma. Little is known about genetic abnormalities in borderline tumors because of the difficulty of growing them in culture for chromosome studies, and because the low ratio of tumor to nontumor cells can interfere with molecular genetic examination. To circumvent these problems, we performed comparative genomic hybridization (CGH) on 10 serous borderline tumors from nine patients, using microdissection to enrich the samples for tumor DNA and reduce contamination from stromal and inflammatory cells. CGH analysis revealed that three of the tumors had detectable chromosomal imbalances, whereas seven were in a balanced state. In those tumors with imbalances, the number of abnormalities ranged from 3–6 per tumor. Additional studies by fluorescence in situ hybridization (FISH) on disaggregated nuclei confirmed the imbalances detected by CGH, revealed one tumor to be hypertriploid, and indicated that the remaining tumors were diploid and in a balanced state. All abnormalities observed in the aneuploid cases are consistent with chromosomal aberrations previously reported for ovarian carinomas, providing further evidence that some borderline tumors are part of a continuum of tumor progression. These results also suggest that there may be different mechanisms leading to borderline tumor formation, including one associated with multiple chromosomal imbalances, and others that do not involve imbalances detectable by CGH. Genes Chromosomes Cancer 25:307–315, 1999. © 1999 Wiley‐Liss, Inc.
It is unclear whether ovarian borderline tumors (tumors of low malignant potential) are independent entities or whether they are part of a continuum of tumor progression that culminates in ovarian carcinoma. Little is known about genetic abnormalities in borderline tumors because of the difficulty of growing them in culture for chromosome studies, and because the low ratio of tumor to nontumor cells can interfere with molecular genetic examination. To circumvent these problems, we performed comparative genomic hybridization (CGH) on 10 serous borderline tumors from nine patients, using microdissection to enrich the samples for tumor DNA and reduce contamination from stromal and inflammatory cells. CGH analysis revealed that three of the tumors had detectable chromosomal imbalances, whereas seven were in a balanced state. In those tumors with imbalances, the number of abnormalities ranged from 3–6 per tumor. Additional studies by fluorescence in situ hybridization (FISH) on disaggregated nuclei confirmed the imbalances detected by CGH, revealed one tumor to be hypertriploid, and indicated that the remaining tumors were diploid and in a balanced state. All abnormalities observed in the aneuploid cases are consistent with chromosomal aberrations previously reported for ovarian carinomas, providing further evidence that some borderline tumors are part of a continuum of tumor progression. These results also suggest that there may be different mechanisms leading to borderline tumor formation, including one associated with multiple chromosomal imbalances, and others that do not involve imbalances detectable by CGH. Genes Chromosomes Cancer 25:307–315, 1999. © 1999 Wiley-Liss, Inc.
Chromosome band 8q21 is frequently overrepresented in human cancer, but to date no 8q21 target gene has been proposed. The hD52 (TPD52) gene is of potential significance in breast and other cancers due to its location and expression pattern. Fine mapping of hD52 placed this locus within the peak of the 8q21 amplicon delineated in the SK-BR-3 breast carcinoma cell line, and a positive association between hD52 gene dosage and transcript levels was subsequently demonstrated in four breast carcinoma cell lines, including SK-BR-3. Increased copy number (ICN) was measured using Southern blot analyses in 3/32 human breast carcinomas at hD52, and the related hD54 gene in 20q13.2–q13.3. Subsequent immunohistochemical analysis of hD52 expression in 19 breast carcinomas with varying hD52 gene dosages demonstrated a significant positive association between hD52 dosage and hD52 expression using a Spearman rank correlation coefficient (rs = 0.573, α = 0.01) and a Wilcoxon rank-sum test (α = 0.05). On the basis of its map location and expression pattern in breast carcinoma, we therefore propose hD52 as a candidate target gene at chromosome band 8q21. Genes, Chromosomes and Cancer 29:48–57, 2000. © 2000 Wiley-Liss, Inc.
Genomic DNA copy number alterations are key genetic events in the development and progression of human cancers. Here we report a genome-wide microarray comparative genomic hybridization (array CGH) analysis of DNA copy number variation in a series of primary human breast tumors. We have profiled DNA copy number alteration across 6,691 mapped human genes, in 44 predominantly advanced, primary breast tumors and 10 breast cancer cell lines. While the overall patterns of DNA amplification and deletion corroborate previous cytogenetic studies, the high-resolution (gene-by-gene) mapping of amplicon boundaries and the quantitative analysis of amplicon shape provide significant improvement in the localization of candidate oncogenes. Parallel microarray measurements of mRNA levels reveal the remarkable degree to which variation in gene copy number contributes to variation in gene expression in tumor cells. Specifically, we find that 62% of highly amplified genes show moderately or highly elevated expression, that DNA copy number influences gene expression across a wide range of DNA copy number alterations (deletion, low-, mid- and high-level amplification), that on average, a 2-fold change in DNA copy number is associated with a corresponding 1.5-fold change in mRNA levels, and that overall, at least 12% of all the variation in gene expression among the breast tumors is directly attributable to underlying variation in gene copy number. These findings provide evidence that widespread DNA copy number alteration can lead directly to global deregulation of gene expression, which may contribute to the development or progression of cancer.
Ninety percent of ovarian cancers in the Western world are epithelial cancers derived from the surface epithelium of the ovary and its inclusion cysts. The so-called surface epithelium is mesothelium that comes to resemble epithelium as it is reflected over the surfaces of the ovaries. At various ages, but particularly in women in the reproductive, menopausal, and postmenopausal age groups, this epithelium migrates into the ovarian stroma to form inclusion cysts. These cysts probably results from a dynamic interplay of surface epithelium and underlying ovarian stroma, but can also develop as a result of periovarian adhesions. There is abundant evidence that their formation is not related to repair of ovulation. It is generally accepted that benign and malignant ovarian epithelial tumors arise from surface epithelium and its cystic derivatives because they both, but particularly the latter, have a potential to differentiate into epithelia similar to those of normal müllerian derivation (tubal, endometrial, and endocervical epithelia) and their tumors resemble those of the fallopian tube, endometrium, and endocervix. Also, both intraepithelial carcinomas and precarcinomatous lesions can be observed in the surface epithelium and its cystic derivatives. These carcinomas may arise de novo or as a transformation of pre-existing benign tumors and non-neoplastic lesions of similar derivation. Surface epithelial inclusion cysts have a greater propensity to undergo neoplasia than does the surface epithelium itself. This difference has been recognized for many years most epithelial ovarian tumors are intraparenchymal, rather than being located on the ovarian surface. More recent evidence includes the immunohistochemical demonstration of various ovarian carcinoma antigens far more frequently in inclusion cyst epithelium than in surface epithelium; and the much more frequent presence of tubal metaplasia in the cyst epithelium than in the surface epithelium. Tubal metaplasia is encountered in non-neoplastic ovaries contralateral to ovarian carcinomas two to three times as frequently as in control ovaries, suggesting that the metaplastic epithelium is more prone to the development of carcinoma that non-metaplastic epithelium. Carcinoma precursors occur in the ovary, as in the cervix and endometrium, but have been reported only rarely because they are easily overlooked and have not been searched for by pathologists.
The genetic changes underlying the development of resistance to the platinum-containing drugs are poorly defined. We analyzed six resistant cell lines using comparative genomic hybridization (CGH) in order to screen and identify possible genetic changes in common. We compared parental 2008 and A2780 human ovarian cancer cells to sublines selected for resistance to cisplatin (DDP) (2008/C8, 2008/C13*5.25, 2008/A, A2780/CP); we also compared 2008 cells to sublines selected for resistance to antimonite (2008/H) and arsenite (2008/I) which demonstrated cross-resistance to DDP. DNA samples from the resistant cell lines were hybridized against DNA from the parental cells rather than from normal human cells to permit detection of only those changes associated with the development of resistance. The DNA sequence copy number changes were surprisingly numerous in the DDP, antimony, and arsenite-resistant variants of the 2008 cell line and most of the chromosomes were affected. On the other hand, in the A2780/CP subline only a few changes were found and these were limited to just four chromosomes. The most common findings among the DDP-resistant cell lines were gains of material from chromosomes or chromosome arms 2q (5 out of 6 lines), 4 (4/6), 6q (5/6), and 8q (4/6). Deletions were observed on chromosomes or chromosome arms 2p (4/6), X (4/6), 7p (5/6), 11p (4/6), and 13 (4/6). The most frequently involved chromosomal regions, affected in the majority of cell lines, were: gain of 2q14.1-q33, 4p15.2-p13, 4q22-q25, 4q31.1-q34, 6q13-q16, 8q12-q21.2, and loss of Xp22.2-q21, 7p21-p14, 11cen-p14 in sublines of 2008, and loss of 2pter-p22 and 13q21 in sublines of 2008 and A2780. The results suggest that the acquired resistance and cross-resistance to DDP in these cell lines was associated with substantial genomic instability, quite unlike the changes observed in association with the development of resistance to drugs participating in the multidrug resistance phenotype.
It is unclear whether ovarian borderline tumors (tumors of low malignant potential) are independent entities or whether they are part of a continuum of tumor progression that culminates in ovarian carcinoma. Little is known about genetic abnormalities in borderline tumors because of the difficulty of growing them in culture for chromosome studies, and because the low ratio of tumor to nontumor cells can interfere with molecular genetic examination. To circumvent these problems, we performed comparative genomic hybridization (CGH) on 10 serous borderline tumors from nine patients, using microdissection to enrich the samples for tumor DNA and reduce contamination from stromal and inflammatory cells. CGH analysis revealed that three of the tumors had detectable chromosomal imbalances, whereas seven were in a balanced state. In those tumors with imbalances, the number of abnormalities ranged from 3-6 per tumor. Additional studies by fluorescence in situ hybridization (FISH) on disaggregated nuclei confirmed the imbalances detected by CGH, revealed one tumor to be hypertriploid, and indicated that the remaining tumors were diploid and in a balanced state. All abnormalities observed in the aneuploid cases are consistent with chromosomal aberrations previously reported for ovarian carinomas, providing further evidence that some borderline tumors are part of a continuum of tumor progression. These results also suggest that there may be different mechanisms leading to borderline tumor formation, including one associated with multiple chromosomal imbalances, and others that do not involve imbalances detectable by CGH. Genes Chromosomes Cancer 25:307-315, 1999.
The histopathologic grade of ovarian epithelial carcinoma has generally been found to be of prognostic significance, but the grading system used has varied among published reports, and often has not been specified at all. The major proposed grading systems are reviewed, and a new system is proposed, which is modeled on the Nottingham system of breast cancer grading and is designed to be applied to all invasive epithelial carcinomas of the ovary. Results obtained in studies using this system are presented. When grading is compared with histopathologic typing of ovarian carcinoma, the latter is less valuable in predicting survival but better at predicting tumor responsiveness to chemotherapy, and can also suggest the chemotherapeutic agents to be used. Thus, both grade and type should be specified in the surgical pathology report for any ovarian carcinoma.
Genetic abnormalities were detected by comparative genomic hybridization (CGH) in 12 ovarian clear cell adenocarcinomas. DNA sequence copy number abnormalities (CNAs) occurring in more than 20% of the cancers included increased copy numbers of 8q11-q13, 8q21-q22, 8q23, 8q24-qter, 17q25-qter, 20q13-qter and 21q22-qter and reduced copy numbers of 19p. Increases in copy numbers of 8q11-q13, 8q21-q22, 8q23 and 8q24-qter occurred more frequently in disease-free patients than in recurrent/non-surviving patients (p < 0.05). However, increases in copy numbers of 17q25-qter and 20q13-qter occurred more frequently in recurrent/non-surviving patients than in disease-free patients (p < 0.05). Furthermore, increases in copy numbers of 17q25-qter and 20q13-qter occurred together (p < 0.05). Additionally, there were negative correlations between increases in copy numbers of 8q21-q22 and 17q25-qter, and between 8q21-q22 and 20q13-qter (p < 0.05). It appears that ovarian clear cell adenocarcinomas can be classified into two subtypes, one being cancer with an increase in copy numbers of 8q and the other being cancer with increases in copy numbers of 17q25-qter and 20q13-qter.
Chromosome band 8q21 is frequently overrepresented in human cancer, but to date no 8q21 target gene has been proposed. The hD52 (TPD52) gene is of potential significance in breast and other cancers due to its location and expression pattern. Fine mapping of hD52 placed this locus within the peak of the 8q21 amplicon delineated in the SK-BR-3 breast carcinoma cell line, and a positive association between hD52 gene dosage and transcript levels was subsequently demonstrated in four breast carcinoma cell lines, including SK-BR-3. Increased copy number (ICN) was measured using Southern blot analyses in 3/32 human breast carcinomas at hD52, and the related hD54 gene in 20q13.2-q13.3. Subsequent immunohistochemical analysis of hD52 expression in 19 breast carcinomas with varying hD52 gene dosages demonstrated a significant positive association between hD52 dosage and hD52 expression using a Spearman rank correlation coefficient (r(s) = 0.573, alpha = 0.01) and a Wilcoxon rank-sum test (alpha = 0.05). On the basis of its map location and expression pattern in breast carcinoma, we therefore propose hD52 as a candidate target gene at chromosome band 8q21.
In the current study the authors attempted to evaluate genetic alterations in a large set of primary ovarian carcinomas and to compare the genetic findings with clinical parameters such as grade of tumor differentiation. This strategy was applied to identify chromosomal regions containing genes associated with tumor progression.
Genetic imbalances were assessed in 106 primary ovarian carcinomas using comparative genomic hybridization (CGH). CGH was applied because it is a powerful tool with which to screen the entire genome of a tumor for genetic changes by highlighting regions of altered DNA sequence copy numbers (deletions and amplifications). Multivariate statistical standard procedures were used to determine an association between tumor grading and genetic alterations.
One hundred three carcinomas showed aberrant CGH profiles. The most frequent alterations were amplifications of 8q, 1q, 20q, 3q, and 19p, which occurred in 69-53% of tumors, and underrepresentations of 13q, 4q, and 18q, which occurred in 54-50% of tumors. Undifferentiated ovarian carcinomas (World Health Organization Grade 3) were found to be correlated significantly with underrepresentation of 11p and 13q as well as with overrepresentation of 8q and 7p (P = 0.001, 0.001, 0.01, and 0.027, respectively). However, 12p underrepresentation and 18p overrepresentation were significantly more frequent in well and moderately differentiated tumors (P = 0.01 and 0.004, respectively). To facilitate the interpretation and clinical application of the results of the current study, the significant aberrations were translated into a score system. This score system can be used easily for the prediction of an undifferentiated phenotype with a specificity and sensitivity of 79% and 86%, respectively.
The current study data show that primary ovarian carcinomas are based on consistent genetic alterations that most likely are important for the development of this tumor entity. The correlation between certain aberrations and undifferentiated carcinomas may help to discriminate between primary and secondary genetic events and may indicate the location of those genes involved in cellular functions associated with tumor progression and the development of anaplastic and aggressive phenotypes.
Recent studies have subdivided serous borderline tumors into 2 categories: atypical proliferative serous tumors (APSTs), which have a relatively benign course, and micropapillary serous carcinomas (MPSCs), which behave like low-grade carcinoma. This study was undertaken to determine, using comparative genomic hybridization (CGH), whether cytogenetic changes support this hypothesis. Nine cases of APST, 10 of MPSC, and 11 of invasive serous carcinoma (SC) were analyzed by CGH. Tumor DNA was extracted from frozen or paraffin-embedded tissue from the primary ovarian tumor, using either sections with at least 70% tumor cells or tissue after relative enrichment by microdissection. Chromosomal imbalances were identified in 3 of 9 APST, 6 of 10 MPSC, and 11 of 11 SC. Three or more chromosomal imbalances were found in 0 of 9 APST, 4 of 10 MPSC, and 9 of 11 SC. Recurrent copy number alterations were grouped into 4 classes correlating with the different tumor types. Class I changes were present in APST and in MPSC or SC and included +8q (7 of 11 SC, 2 of 10 MPSC, 2 of 9 APST), -9p (5 of 11 SC, 0 of 10 MPSC, 1 of 9 APST), and +12 (+12p in 3/11 SC, +12 in 2 of 10 MPSC, +12 in 1 of 9 APST). Class II changes were found only in MPSC and SC, but not in APST. The most frequent examples were +3q (10 of 11 SC, 1 of 10 MPSC), -4q (5 of 11 SC, 1 of 10 MPSC), and -17p (5 of 11 SC, 1 of 10 MPSC). Class III changes were limited to SC, like -16q (7 of 11 SC) and -18q (6 of 11 SC). Class VI changes were unique to MPSC. Gain of 16p (3 of 10 MPSC) was the only aberration in this group. This aberration was not only unique to MPSC but was also the most frequent finding in MPSC. These data support the hypothesis that noninvasive serous tumors of the ovary can be subdivided into 2 categories: APST and MPSC. The number of imbalances in MPSC is substantially higher than in APST and lower than in SC. Some changes in MPSC are shared with SC and APST and others with SC only, suggesting that a subset of MPSC may represent a stage in progression from APST to SC. Other cases of MPSC with independent genetic alterations may represent another subset of tumors that are a distinct entity from APST and SC.
The genetic changes involved in the pathogenesis of ovarian carcinoma are not completely understood. To investigate this matter, we studied paraffin-embedded, microdissected tissue of 47 ovarian epithelial tumors (9 adenomas, 11 tumors of low malignant potential [LMP], 14 serous carcinomas, and 13 nonserous carcinomas) using comparative genomic hybridization (CGH). (The primary data used in this study are available at our CGH online tumor database at http://amba.charite.de/cgh.) Chromosomal imbalances were found in 1 serous adenoma and in 7 LMP tumors. In the latter the alterations appeared randomly and showed no overlap with alterations found in invasive carcinomas. Although the mean aberration number of low-grade serous carcinomas was comparable to LMP tumors, the imbalances of the former occurred with high incidence (>50%) and were found at different localizations. High-grade serous carcinomas had more than twice as much chromosomal imbalances as low-grade serous carcinomas and also had pronounced alterations. In serous carcinomas, gains were found on 3q, 6p, 7, 8q, and 20, and losses were found on 4q, 6q, 12q, 13q, and 16q. Comparing serous and nonserous carcinomas, the mean aberration number was comparable, but the number of high incidence changes was lower, and the most frequent imbalances were losses on 13q and gains on 20p. Overlapping alterations occurring in serous and nonserous carcinomas were gains on 3q and 6p, as well as losses on 4q. Chromosomal imbalances associated with poor prognosis of ovarian carcinomas were gains on 6p, 7q, and 13q and losses on 15q, 17p, 18q, and 21q. Our data indicate that serous LMP tumors and invasive carcinomas have different genetic aberrations, indicating that invasive carcinomas do not arise from preexisting serous LMP tumors. On the other hand, there are common genetic abnormalities in serous and nonserous carcinomas, suggesting that they have very early lesions in common but take different paths of further development.
We analyzed 25 ovarian borderline tumors (13 serous and 12 mucinous tumors) by comparative genomic hybridization (CGH). Genomic imbalance was detected in 85% of serous tumors and 75% of mucinous tumors. Different patterns of genomic alterations were identified in serous and mucinous tumors. Gain of the X chromosome was common in both serous (30%) and mucinous (42%) tumors. However, gain of chromosome 8 was detected exclusively in 38% of serous and mixed sero-mucinous tumors, but not in any pure mucinous tumors. According to the present and previous studies, gain of chromosome 8 is the most common abnormality in borderline serous tumors. Gain of the same chromosome is also common in high grade and advanced stage serous carcinomas, but uncommon in early stage serous carcinomas. In addition gain of chromosome X is common in borderline serous and mucinous tumors, while loss of chromosome X is predominant in invasive carcinomas. These findings do not support the multi-step progression theory from borderline tumor to high-grade, advanced stage carcinoma, but indicate that the borderline ovarian tumor is a distinct entity. Genes in chromosome 8 may be critical for the development and the differentiation of borderline serous tumors.
The purpose of this study is to comparatively characterize genomic imbalances in primary and recurrent ovarian serous carcinomas and to identify genomic alterations that may be used as a marker for prognosis.
Twenty ovarian serous carcinomas were studied by comparative genomic hybridization (CGH).
Genomic alterations were found in all of the tumors. The most common regions involving gain of DNA copy numbers are 1q41q44, 8q22q24, 19p12q13.1, 20q12q13, 3q26q29, 12p12p13, 2p22p25, 7p14p21, 5p15.2p15.3, and 17q22q25. The most common regions with loss of DNA copy numbers are Xp11.2q13, 4q31q35, Xp21p22.3, 18q22q23, 13q22q31, 9p22p24, and 16q22q24. High-level gains were detected at chromosomal regions of 1q41q44, 2p22p25, 3q26q29, and 19p12q13.1. Comparative analysis of primary and recurrent tumors showed that gains of 2p22p25, 19p12q13.1, and 20q12q13 and loss of 5q14q22 were more common in the recurrent high-grade tumors. About 85% of the tumors showed increases in DNA copy numbers in the regions (2p and 8q) harboring the myc family gene. Patients with tumor containing fewer than seven chromosomal aberrations showed longer survival time.
The myc oncogene family may play a role in the pathogenesis of ovarian serous carcinomas. Our study suggests that tumors with gains of 2p22p25, 19p12q13.1, and 20q12q13 and loss of 5q14q22 may be at high risk for recurrence. Furthermore, the patients' survival time inversely correlates with the numbers of chromosomal alterations found in their tumors. CGH analysis may have a clinical application in predicting prognosis and risk of recurrence in patients with ovarian serous carcinomas.
D52 (TPD52)-like proteins are coiled-coil motif-bearing proteins first identified through their expression in human breast carcinoma, which have been proposed to represent signalling intermediates and regulators of vesicle trafficking. D52-like gene transcripts are subject to alternative splicing, with sequences encoding a region termed insert 3 being affected in all three D52-like genes. We have now identified a 14-3-3 binding motif within one of two alternatively spliced exons encoding insert 3. As predicted from the distribution of 14-3-3 binding motifs in four hD52-like bait proteins tested, only a hD53 isoform encoding a 14-3-3 binding motif bound both 14-3-3beta and 14-3-3zeta preys in the yeast two-hybrid system. Since D53 proteins carrying 14-3-3 binding motifs are predicted to be widely expressed, polyclonal antisera were derived to specifically detect these isoforms. Using soluble protein extracts from breast carcinoma cell lines, pull-down assays replicated interactions between recombinant 14-3-3beta and 14-3-3zeta isoforms and exogenously expressed hD53, and co-immunoprecipitation analyses demonstrated interactions between endogenous 14-3-3 and both endogenously and exogenously-expressed hD53 protein. Co-expressed hD53 and 14-3-3 proteins were similarly demonstrated to co-localise within the cytoplasm of breast carcinoma cell lines. These results identify 14-3-3 proteins as partners for hD53, and alternative splicing as a mechanism for regulating 14-3-3 binding.
Gains in the long arm of chromosome 8 (8q) are believed to be associated with poor outcome and the development of hormone-refractory prostate cancer. Based on a meta-analysis of gene expression microarray data from multiple prostate cancer studies (D. R. Rhodes et al., Cancer Res 2002;62:4427-33), a candidate oncogene, Tumor Protein D52 (TPD52), was identified in the 8q21 amplicon. TPD52 is a coiled-coil motif-bearing protein, potentially involved in vesicle trafficking. Both mRNA and protein levels of TPD52 were highly elevated in prostate cancer tissues. Array comparative genomic hybridization and amplification analysis using single nucleotide polymorphism arrays demonstrated increased DNA copy number in the region encompassing TPD52. Fluorescence in situ hybridization on tissue microarrays confirmed TPD52 amplification in prostate cancer epithelia. Furthermore, our studies suggest that TPD52 protein levels may be regulated by androgens, consistent with the presence of androgen response elements in the upstream promoter of TPD52. In summary, these findings suggest that dysregulation of TPD52 by genomic amplification and androgen induction may play a role in prostate cancer progression.
Ovarian cancer is the leading cause of death among patients with gynecological cancers, but the biology of these tumors is still among the least understood of all major human malignancies. In this study, comparative genomic hybridization was used to determine chromosomal alterations in 98 stage III serous papillary adenocarcinomas. The tumors were grouped according to survival and the main prognostic factors stage and surgical outcome. There were chromosomal imbalances that were significantly more common in tumors from patients who died than in tumors from patients who survived: gains of 1q24-qter and losses of 4p, 4q31.1-qter, 5q12-q22, 8p, 16q, and X. Furthermore, we observed that gains of 8q23-8q24.2 and losses of 4p, 4q13-4q26, 4q31.1-qter, 5q12-q22, 8p, and 16q were significantly more common in tumors from patients with macroscopic residual tumor after primary surgery, compared to tumors from those who had undergone radical surgery. Gains of 3q13.3-qter, 6p, 7q21-q31, and 11q13-q23 and losses of 4q31.1-qter and 16q were more common in stage IIIc tumors than in stage IIIa+b tumors. On the basis of our results, we suggest that there are biological differences among the groups mentioned above and that absence of chromosomal aberrations in specific regions predicts a good clinical outcome for individual patients.
Breast cancers can display distinct clinical characteristics in different ethnic populations. Previous studies involving European and United States patients have shown that breast tumors can be divided by their gene expression profiles into distinct "molecular subtypes." In this report, we surveyed a series of invasive and preinvasive breast tumors from Asian-Chinese patients to investigate whether similar subtypes could also be observed in this ethnic group. Experimental Design and
An analysis of expression profiles generated from 11 nonmalignant breast tissues, 17 ductal carcinomas in situ (DCIS) and 98 invasive carcinomas identified three broad molecular subtypes of breast [estrogen receptor (ER)+, ERBB2+ and ER-] in the Asian-Chinese population. These subtypes were highly similar to the "Luminal," "ERBB2+," and "Basal" molecular subtypes defined in previous studies, and the subtype-specific expression signatures were also observed in preinvasive DCIS tumors. By comparing the expression profiles of nonmalignant DCIS and invasive breast cancers for two subtypes (ER+ and ERBB2+), we identified several genes that were regulated in both a common and subtype-specific manner during the normal/DCIS and DCIS/invasive carcinoma transitions. Several of these genes were validated by comparison with another recently published similar, but not identical, study.
Our results suggest that molecularly similar subtypes of breast cancer are indeed broadly conserved between Asian and Caucasian patients, and that these subtypes are already present at the preinvasive stage of carcinogenesis. To our knowledge, this study is among the first to directly compare the expression profiles of breast tumors across two different ethnic populations.
Our purpose was to get an overview of the genetic events leading to the development of familial and sporadic ovarian tumors and to identify chromosomal regions that may contain genes important in tumor progression.
The comparative genomic hybridization (CGH) technique was employed in a total of 46 epithelial ovarian or peritoneal tumors: 27 sporadic tumors, 11 tumors disected from BRCA1 mutation (185delAG) carriers, and eight from BRCA2 mutation (6174delT) carriers (familial tumors).
The average number of genetic alterations (deletions and amplifications) was significantly (alpha=0.0069) higher in familial tumors (9.17 +/- 4.25 alterations per tumor in the BRCA1 mutation carriers and 7.25 +/- 6.06 in the BRCA2 mutation carriers) compared to the sporadic group (4.26 +/- 3.61 alterations per tumor). The pattern of the chromosome amplifications resembled in the three groups and the most common amplifications detected were at chromosomes 8q, 3q, and 2q. The pattern of the chromosomal deletions varied between the groups. Among the BRCA1 group, the most common deletions were in chromosomes 9 and 19. The BRCA2 group showed a lower frequency of deletions. Deletion of chromosome 16 and 22 were the most frequent ones. No specific chromosomal deletion was significantly indicated in the sporadic group.
Familial ovarian tumors exhibit a significantly higher number of chromosomal aberrations and genomic imbalances and nonrandom genetic changes were characterized in the BRCA1 and BRCA2 groups.
Comparative genomic hybridization detects genetic imbalances in primary ovarian carcinomas as correlated with grade of differentiation Genetic analysis of early-versus late-stage ovarian tumors
- M Kiechle
- A Jacobsen
- Schwarz
- U Boeger
- J Hedderich
- J Pfisterer
- N Arnold
- V Shridhar
- J Lee
- A Pandita
- S Iturria
- R Avula
- J Staub
- M Morrissey
- E Calhoun
- A Sen
- K Kalli
- G Keeney
- P Roche
Kiechle M, Jacobsen A, Schwarz-Boeger U, Hedderich J, Pfisterer J, Arnold N. Comparative genomic hybridization detects genetic imbalances in primary ovarian carcinomas as correlated with grade of differentiation. Cancer 2001;91:534–40. 5. Shridhar V, Lee J, Pandita A, Iturria S, Avula R, Staub J, Morrissey M, Calhoun E, Sen A, Kalli K, Keeney G, Roche P, et al. Genetic analysis of early-versus late-stage ovarian tumors. Cancer Res 2001;61:5895–904.
Characterization of a leucine zipper-containing protein identified by retroviral insertion in avian neuroretina cells Identification of Src transformation fingerprint in human colon cancer
- V Proux
- S Provot
- Felder
- M-P Schmittbuhl
- D Laugier
- G Calothy
- Marx
- Malek Rl
- Rb Irby
- Qm Guo
- K Lee
- S Wong
- M He
- J Tsai
- B Frank
- Liu
- J Quackenbush
- R Jove
- Tj Yeatman
Proux V, Provot S, Felder-Schmittbuhl M-P, Laugier D, Calothy G, Marx M. Characterization of a leucine zipper-containing protein identified by retroviral insertion in avian neuroretina cells. J Biol Chem 1996;271:3079–7. 21. Malek RL, Irby RB, Guo QM, Lee K, Wong S, He M, Tsai J, Frank B, Liu ET, Quackenbush J, Jove R, Yeatman TJ, et al. Identification of Src transformation fingerprint in human colon cancer. Oncogene 2002;21:7256–65.
- Wasenius
- Kiechle