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Breast cancer expression of CD163, a macrophage scavenger receptor, is related to early distant recurrence and reduced patient survival
International Journal of Cancer
Abstract
Cells of the monocyte/macrophage lineage are important for tumour cell migration, invasion and metastasis. Fusion between macrophages and cancer cells in animal models in vitro and in vivo causes hybrids with increased metastatic potential. Primary breast cancer cells were characterized for macrophage antigens to test if phenotypic resemblance to macrophages is related to early distant recurrence. Immunostaining for CD163, MAC387 and CD68 was performed in a breast cancer tissue micro array from 127 patients consequently followed up for a median of 13 years. Tumour-associated macrophages expressed all 3 antigens. The breast cancers expressed CD163 to 48%, MAC387 to 14% while CD68 was not expressed. TGF-beta staining intensity was positively related to both CD163 and MAC387 expression. Expression of CD163 in the cancer cells was compared to their DNA ploidy, Nottingham Histological Grade, TNM-stage, node state, presence of estrogen receptors and occurrence of distant metastases and survival. Cancers of a more advanced histological grade expressed CD163 to a higher extent. Cells expressing MAC387 were more common in cancers with a high proportion of CD163 positive cells. Multivariate analysis showed that expression of the macrophage antigen CD163 in breast cancer cells has a prognostic impact on the occurrence of distant metastases and reduced patient survival time.
... Assuming that expression of epithelial or hematopoietic antigens in cancer cells is attributed to previous cell-fusion events as considered by several studies [19,20,44,[46][47][48], the amount of cancer hybrid cells within a primary tumor could be high. Data of Shabo and colleagues revealed that in approximately 48% of breast cancer patients the expression of the macrophage antigen CD163 was found in more than 25% of the cancer cells [48]. ...
... Assuming that expression of epithelial or hematopoietic antigens in cancer cells is attributed to previous cell-fusion events as considered by several studies [19,20,44,[46][47][48], the amount of cancer hybrid cells within a primary tumor could be high. Data of Shabo and colleagues revealed that in approximately 48% of breast cancer patients the expression of the macrophage antigen CD163 was found in more than 25% of the cancer cells [48]. Similar findings were presented for colorectal tumors, whereby CD163 expression was found in 23% of the patient cancer cells [47]. ...
... Expression of pan-hematopoietic markers, such as CD45, and/or macrophage epitopes on cancer cells has also been suggested as putative cell-fusion markers [18][19][20]44,[46][47][48]. However, hematopoietic lineage epitopes on cancer cells can be attributed to genomic instability, raising concerns about concluding that such cells were exclusively derived from cancer-cell fusions. ...
Fusion of cancer cells either with other cancer cells (homotypic fusion) in local vicinity of the tumor tissue or with other cell types (e.g., macrophages, cancer-associated fibroblasts (CAFs), mesenchymal stromal-/stem-like cells (MSC)) (heterotypic fusion) represents a rare event. Accordingly, the clinical relevance of cancer-cell fusion events appears questionable. However, enhanced tumor growth and/or development of certain metastases can originate from cancer-cell fusion. Formation of hybrid cells after cancer-cell fusion requires a post-hybrid selection process (PHSP) to cope with genomic instability of the parental nuclei and reorganize survival and metabolic functionality. The present review dissects mechanisms that contribute to a PHSP and resulting functional alterations of the cancer hybrids. Based upon new properties of cancer hybrid cells, the arising clinical consequences of the subsequent tumor heterogeneity after cancer-cell fusion represent a major therapeutic challenge. However, cellular partners during cancer-cell fusion such as MSC within the tumor microenvironment or MSC-derived exosomes may provide a suitable vehicle to specifically address and deliver anti-tumor cargo to cancer cells.
... Several in vitro and in vivo animal studies have demonstrated that cancer cells exhibit fusogenic properties and may either homo-or hetero-hybridize with the generation of new cancer hybrid cells displaying altered properties [138,164,[180][181][182][183][184][185][186][187][188][189][190][191][192][193][194][195][196][197]. ...
... A common approach to search for putative heterotypic fusion is to seek the expression of non-cancer specific epitopes in cancer hybrid cells, such as macrophage, hematopoietic, or epithelial antigens [138,[182][183][184]191,194]. However, the expression of hematopoietic and epithelial lineage markers of cancer cells can also be traced back to genomic instability, which limits this strategy. ...
... In any case, Shabo and colleagues detected the expression of macrophage antigens DAP12, MAC387, and CD163 in human breast cancer and colorectal cancer tissues [182][183][184]197]. Increased CD163 expression levels were related to early recurrence and reduced overall survival of afflicted patients [183,184], suggesting CD163 as a suitable prognostic factor. ...
The generation of cancer hybrid cells by intra-tumoral cell fusion opens new avenues for tumor plasticity to develop cancer stem cells with altered properties, to escape from immune surveillance, to change metastatic behavior, and to broaden drug responsiveness/resistance. Genomic instability and chromosomal rearrangements in bi- or multinucleated aneuploid cancer hybrid cells contribute to these new functions. However, the significance of cell fusion in tumorigenesis is controversial with respect to the low frequency of cancer cell fusion events and a clonal advantage of surviving cancer hybrid cells following a post-hybrid selection process. This review highlights alternative processes of cancer hybrid cell development such as entosis, emperipolesis, cannibalism, therapy-induced polyploidization/endoreduplication, horizontal or lateral gene transfer, and focusses on the predominant mechanisms of cell fusion. Based upon new properties of cancer hybrid cells the arising clinical consequences of the subsequent tumor heterogeneity after cancer cell fusion represent a major therapeutic challenge.
... The process of hybrid cell formation between a tumor and an immune cell has been documented in cell-culture and animal models [9,19]. While the source of these cells in circulation is believed to be the primary and/or metastatic tumor, a few studies have demonstrated their presence, mainly using immunohistochemistry, in the primary tumor using a limited number of markers and candidate approaches [23][24][25][26][27][28]. Due to a lack of markers and a consensus concerning the definition of these cells, several different proteins, including CD14, CD45, CD68, and/or CD163, to identify immune lineage and EPCAM and/or pancytokeratins, including CK8, CK9, and CK19, to identify epithelial lineage were used to identify and characterize these cells from circulation and in tumor biopsies [5][6][7][8]18,[23][24][25][26][27][28][29][30][31][32][33][34]. ...
... While the source of these cells in circulation is believed to be the primary and/or metastatic tumor, a few studies have demonstrated their presence, mainly using immunohistochemistry, in the primary tumor using a limited number of markers and candidate approaches [23][24][25][26][27][28]. Due to a lack of markers and a consensus concerning the definition of these cells, several different proteins, including CD14, CD45, CD68, and/or CD163, to identify immune lineage and EPCAM and/or pancytokeratins, including CK8, CK9, and CK19, to identify epithelial lineage were used to identify and characterize these cells from circulation and in tumor biopsies [5][6][7][8]18,[23][24][25][26][27][28][29][30][31][32][33][34]. THCs were described in the circulation of patients with several different solid cancers, including colon, breast, ovarian, pancreatic, renal, esophageal, and melanoma [1,2,[4][5][6][7][8]10,[12][13][14][15]19,20,22,30,31,33,34]. ...
Simple Summary
This study explored a potentially significant player in the spread of metastatic cancer: “hybrid cells” (HCs) combining features of both epithelial (common in tissues) and immune cells (such as macrophages). HCs were found in more than one type of tumor (THC) and showed a unique transcriptional profile including the activation of functional pathways, potentially explaining their mobility, dissemination into circulation, and metastatic progression. Normal healthy tissue also showed hybrid cells (NHC), but they were rare and could be easily distinguished from THCs based on their gene expression profile. The study also developed a way to identify HCs in large datasets generated at the single-cell level, paving the way for further research on their function and as potential therapeutic targets.
Abstract
Metastatic cancer is a leading cause of death in cancer patients worldwide. While circulating hybrid cells (CHCs) are implicated in metastatic spread, studies documenting their tissue origin remain sparse, with limited candidate approaches using one–two markers. Utilizing high-throughput single-cell and spatial transcriptomics, we identified tumor hybrid cells (THCs) co-expressing epithelial and macrophage markers and expressing a distinct transcriptome. Rarely, normal tissue showed these cells (NHCs), but their transcriptome was easily distinguishable from THCs. THCs with unique transcriptomes were observed in breast and colon cancers, suggesting this to be a generalizable phenomenon across cancer types. This study establishes a framework for HC identification in large datasets, providing compelling evidence for their tissue residence and offering comprehensive transcriptomic characterization. Furthermore, it sheds light on their differential function and identifies pathways that could explain their newly acquired invasive capabilities. THCs should be considered as potential therapeutic targets.
... Among innate immune cells, tumor-associated macrophages and neutrophils resulted significantly increased in TT. Macrophages have been mainly reported as tumor-promoting cells in many types of tumors [71][72][73][74], through their ability to produce immunosuppressive cytokines, such as interleukin (IL)-10 and IL-1Ra [75]. TAMs are also known to promote tumor angiogenesis, tissue remodeling, and inhibition of the immune response producing IL-10, TGF-β and Indoleamine 2,3-dioxygenase (IDO) instead of IL-12. ...
... These later trajectories lead to the development of regulatory T cells and effector T cells anergy [75]. The density of CD163 + macrophages is associated with poor prognosis and reduced overall survival in CRC, in addition to many other solid tumors [71][72][73][74]. However, recently identified markers have shown extreme heterogeneity among TAM population [42,[76][77][78]. ...
Simple Summary
Consensus Molecular Subtypes have recently been proposed based on molecular and immune landscape of colorectal carcinoma (CRC). Only mismatch repair deficient and hyper-mutated CRC (CRCdMMR) can obtain clinical benefits from immune checkpoint blockades; on the other hand, mismatch repair proficient CRCs (CRCpMMR) have very limited therapeutic options. This study establishes that CRCpMMR displays an immunosuppressive microenvironment containing abundant tumor-associated macrophages (TAMs) and neutrophils, with a reduction in double negative T lymphocytes and B cells and increased exhausted tumor-infiltrating lymphocytes. Poor immunogenicity in CRCpMMR is further supported by interferon gamma (IFN-γ) unresponsiveness of both tumor cells and TAMs.
Abstract
Colorectal carcinoma (CRC) represents a lethal disease with heterogeneous outcomes. Only patients with mismatch repair (MMR) deficient CRC showing microsatellite instability and hyper-mutated tumors can obtain clinical benefits from current immune checkpoint blockades; on the other hand, immune- or target-based therapeutic strategies are very limited for subjects with mismatch repair proficient CRC (CRCpMMR). Here, we report a comprehensive typing of immune infiltrating cells in CRCpMMR. We also tested the expression and interferon-γ-modulation of PD-L1/CD274. Relevant findings were subsequently validated by immunohistochemistry on fixed materials. CRCpMMR contain a significantly increased fraction of CD163⁺ macrophages (TAMs) expressing TREM2 and CD66⁺ neutrophils (TANs) together with decrease in CD4⁻CD8⁻CD3⁺ double negative T lymphocytes (DNTs); no differences were revealed by the analysis of conventional and plasmacytoid dendritic cell populations. A fraction of tumor-infiltrating T-cells displays an exhausted phenotype, co-expressing PD-1 and TIM-3. Remarkably, expression of PD-L1 on fresh tumor cells and TAMs was undetectable even after in vitro stimulation with interferon-γ. These findings confirm the immune suppressive microenvironment of CRCpMMR characterized by dense infiltration of TAMs, occurrence of TANs, lack of DNTs, T-cell exhaustion, and interferon-γ unresponsiveness by host and tumor cells. Appropriate bypass strategies should consider these combinations of immune escape mechanisms in CRCpMMR.
... consistent with a previous investigation by Ivan and colleague [23] that showed that patients with breast cancer are more susceptible to relapse and metastasis and have a poor prognosis. Additionally, high expression of Rab5 was reported to be closely related to the high metastatic characteristics of other tumors [24][25][26]. ...
... In addition, genetic exchange between tumor-associated macrophages and tumor cells could be another mechanism by which M2-like macrophages promote tumorigenesis [38,39]. Intriguingly, breast cancer patients with cancer cells expressing macrophage antigen CD163 are generally vulnerable to distant metastases and short survival [23]. We are interested in the possibility that Rab5 contributes to the occurrence and development of breast cancer by educating macrophages in an exosome-dependent manner. ...
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and current therapeutic strategies are limited in their effectiveness. The expressions of Rab5 and the M2 tumor-associated macrophage marker CD163 in tissues were detected by Western blot. The migration and invasion of cells were determined using a Transwell assay. The expressions of the exosome markers were evaluated by Western blot. The polarization of human macrophages (THP-1) was determined by incubation of THP-1 cells with conditioned medium or exosomes collected from MDA-MB-231 cells with indicated transfections or by a coculture system of THP-1 and MDA-MB-231 cells. The M1 and M2 macrophage markers were evaluated by qRT-PCR. The expression of Rab5 in TNBC was significantly higher than that in normal breast tissue. Rab5 expressions in triple-negative and luminal A breast cancer were higher than those in other molecular subtypes. Higher CD163 expression was observed in triple-negative breast cancer and in triple-negative and luminal B subtypes. Rab5 knockdown suppressed but Rab5 overexpression promoted the migration and invasion capacity of MDA-MB-231 cells. The levels of CD63 and CD9 in the medium of Rab5 knockdown cells were lower than those in control cells, whereas higher levels of CD63 and CD9 were observed in Rab5 overexpression cells. Rab5 knockdown decreased the excretion but did not alter the diameter of the exosomes. Knockdown of Rab5 facilitated the anti-tumor polarization of macrophages, which was partially reversed by Rab5 overexpression. Therefore, Rab5 is expected to be a potential therapeutic target for triple-negative breast cancer.
... In solid tumors, tissue resident and bone marrow-derived infiltrating macrophages represent a major immune component of the tumor microenvironment [5] and enhance invasive growth, matrix remodeling, angiogenesis, and immune suppression [6,7]. Consistent with their pro-tumorigenic phenotypes, the accumulation of tumor-associated macrophages (TAMs) in breast cancer patients is generally associated with poor prognosis, resistance to therapies, and disease recurrence [8][9][10]. Given the significant clinical impact of macrophage density in solid tumors, developing novel non-invasive imaging methods to quantify TAMs has a clear applicative use in breast cancer patients, particularly given the recent incorporation of immune-modulating therapies, such as checkpoint inhibitors, into standard management of these patients [11]. ...
... Imaging of inflammation with ferumoxytol-contrasted breast [Fe]MRI has the potential to yield valuable prognostic and anatomic information for human patients with breast cancer. Infiltration of TAM into the breast cancer generally indicates a poor prognosis in breast cancer patients [2][3][4][5][6][7][8][9][10]. In fact, macrophage CD68 is one of the genes in the standard Oncotype Dx score, a widely used prognostic tool used for patients with early-stage breast cancer. ...
Tumor-associated macrophages (TAMs) in breast cancer regulate inflammation, immunosuppression, angiogenesis, and metastasis. However, TAM imaging remains a clinical challenge. Ferumoxytol has long been an FDA-approved superparamagnetic iron oxide nanoparticle (SPION) preparation used as an intravenous (IV) treatment for iron-deficiency anemia. Given its high transverse relaxivity, ferumoxytol produces a negative image contrast upon cellular uptake in T2-weighted magnetic resonance imaging (MRI) studies. Here we evaluated ferumoxytol as a contrast agent to image/quantify TAMs in an aggressive mouse model of breast cancer: We developed [Fe]MRI to measure the 5-dimensional function c(x,y,z,t), where c is the concentration of nanoparticle iron and {x,y,z,t} is the 4-dimensional set of tumor space-time coordinates. Ferumoxytol SPIONs are readily phagocytosed (~104/cell) by the F4/80+CD11b+ TAMs within breast tumors. Quantitative [Fe]MRIs served to determine both the spatial and the temporal distribution of the SPION iron, and hence to measure [Fe] = c(x,y,z,t), a surrogate for TAM density. In single-dose pharmacokinetic studies, after an IV dose of 5 mg/Kg iron, [Fe]MRI measurements showed that c(x,y,z,t) within breast tumors peaked around [Fe] = 70 μM at 42 h post-administration, and decayed below the [Fe]MRI detection limit (~2 μM) by day 7. There was no SPION uptake in control organs (muscle and adipose tissue). Optical microscopy of tissue sections confirmed that F4/80+CD11b+ TAMs infiltrated the tumors and accumulated SPION iron. Our methodology and findings have translational applications for breast cancer patients.
... For example, cancer hybrid cells were identified in tumors of female patients after a bone marrow transplant with a male donor using the X chromosome contained in the tumor cells, or DNA segments of the donor could be detected in cancer cells using short tandem repeat analysis [56,63,64]. Furthermore, cancer hybrid cells could be identified based on epitopes that are normally not found in cancer cells and are specific to macrophages or epithelial cells, for example [6,58,[65][66][67][68]. ...
Cell fusion is a biological process that is crucial for the development and homeostasis of different tissues, but it is also pathophysiologically associated with tumor progression and malignancy. The investigation of cell fusion processes is difficult because there is no standardized marker. Many studies therefore use different systems to observe and quantify cell fusion in vitro and in vivo. The comparability of the results must be critically questioned, because both the experimental procedure and the assays differ between studies. The comparability of the fluorescence-based fluorescence double reporter (FDR) and dual split protein (DSP) assay was investigated as part of this study, in which general conditions were kept largely constant. In order to be able to induce both a high and a low cell fusion rate, M13SV1 breast epithelial cells were modified with regard to the expression level of the fusogenic protein Syncytin-1 and its receptor ASCT2 and were co-cultivated for 72 h with different breast cancer cell lines. A high number of fused cells was found in co-cultures with Syncytin-1-overexpressing M13SV1 cells, but differences between the assays were also observed. This shows that the quantification of cell fusion events in particular is highly dependent on the assay selected, but the influence of fusogenic proteins can be visualized very well.
... On the other hand, studies have shown increased macrophage infiltration, particularly CD163 + macrophages in the immune microenvironment of STS and in particular LMS [74,75]. Consistent with the immunosuppressive nature of CD163 + macrophages, some reports have shown an association between increased CD163 + infiltration in LMS and worse prognosis [74] which is in line with studies in other cancers [76,77]. Thus, macrophage-directed therapeutics may form a promising strategy in the treatment of LMS. ...
Opinion statement
Leiomyosarcoma (LMS) is one of the more common subtypes of soft tissue sarcomas (STS), accounting for about 20% of cases. Differences in anatomical location, risk of recurrence and histomorphological variants contribute to the substantial clinical heterogeneity in survival outcomes and therapy responses observed in patients. There is therefore a need to move away from the current one-size-fits-all treatment approach towards a personalised strategy tailored for individual patients. Over the past decade, tissue profiling studies have revealed key genomic features and an additional layer of molecular heterogeneity among patients, with potential utility for optimal risk stratification and biomarker-matched therapies. Furthermore, recent studies investigating intratumour heterogeneity and tumour evolution patterns in LMS suggest some key features that may need to be taken into consideration when designing treatment strategies and clinical trials. Moving forward, national and international collaborative efforts to aggregate expertise, data, resources and tools are needed to achieve a step change in improving patient survival outcomes in this disease of unmet need.
... CD68 is a Pan-Macrophage Marker Expressed in M1 and M2 Macrophages, while CD163 is M2-Specific Different subtypes of myeloid cells have an impact on the immunological microenvironment. While there have been findings that showed favorable prognosis in certain studies [95,96], several investigations have consistently demonstrated a significant association between a high abundance of tumor-infiltrating macrophages and unfavorable prognosis in different types of cancers [55,97,98]. Macrophages exhibit heterogeneity and can be categorized into two main subtypes: classically activated macrophages (also known as M1 macrophages or M1 as discussed earlier) that are primarily activated by Th1 cytokines, and alternatively activated macrophages (also known as M2 macrophages or M2) that are primarily activated by Th2 cytokines [99][100][101][102]. ...
... M2 macrophages also stimulate angiogenesis through the production of vascular endothelial growth factors [74]. According to these processes, M2 macrophages play a major role in tumor invasion and metastasis, which typically result in a less favorable clinical outcome for both humans and mice [75,76]. Significantly, it was recently demonstrated that tumorassociated M2 macrophages can have their polarization reversed to the M1 phenotype, thus preventing tumor metastasis by blocking IL-10 signaling [77]. ...
Due to the health emergency created by SARS -CoV-2, the virus that causes the COVID-19 disease, the rapid implementation of a new vaccine technology was necessary. mRNA vaccines, being one of the cutting-edge new technologies, attracted significant interest and offered a lot of hope. The potential of these vaccines in preventing admission to hospitals and
serious illness in people with comorbidities has recently been called into question due to the vaccines' rapidly waning immunity. Mounting evidence indicates that these vaccines, like
many others, do not generate sterilizing immunity, leaving people vulnerable to recurrent infections. Additionally, it has been discovered that the mRNA vaccines inhibit essential
immunological pathways, thus impairing early interferon signaling. Within the framework of COVID-19 vaccination, this inhibition ensures an appropriate spike protein synthesis and a
reduced immune activation. Evidence is provided that adding 100% of N1-methyl-pseudouridine (m1Ψ) to the mRNA vaccine in a melanoma model stimulated cancer growth and metastasis, while non-modified mRNA vaccines induced opposite results, thus suggesting that COVID-19 mRNA vaccines could aid cancer development. Based on this compelling evidence, we suggest that future clinical trials for cancers or infectious diseases should not use mRNA vaccines with a 100% m1Ψ modification, but rather ones with the lower percentage of m1Ψ modification to avoid immune suppression.
... We believe that single staining of CD163 + cells can potentially represent M2-like phenotypic populations. Many investigators have already used CD163 as a marker of M2-like macrophages, showing its prognostic significance in several cancers (29)(30)(31)(32). Thus, we believe that our mSIA, based on CD8 + and CD163 + immune cells, could have the same efficiency as the original SIA. ...
Tumor-infiltrating immune cells, such as lymphocytes and macrophages, have been associated with tumor aggressiveness, prognosis and treatment response in colorectal cancer (CRC). An immune scoring system, Immunoscore (IS), based on tumor-infiltrating T cells in stage I–III CRC, was used to predict prognosis. An alternative immune scoring signature of immune activation (SIA) reflects the balance between anti- and pro-tumoral immune components. The present study aimed to evaluate the prognostic value of modified IS (mIS) and modified SIA (mSIA) in locally advanced pathological T4 (pT4) CRC, including stage IV CRC. Immunohistochemical staining for immune cell markers, such as CD3 (pan-T cell marker), CD8 (anti-tumoral cytotoxic T cell marker) and CD163 (tumor-supportive macrophage marker), in specimens from patients with radically resected pT4 CRC at stages II–IV was performed. mIS levels in the T4 CRC cohort were not associated with prognosis. However, low mSIA levels were associated with low survival. Furthermore, low mSIA was an independent predictor of recurrence in patients with radically resected pT4 CRC. In patients with CRC who did not receive postoperative adjuvant chemotherapy, low mSIA was a major poor prognostic factor; however, this was not observed in patients receiving adjuvant chemotherapy. Evaluation of the tumor-infiltrating immune cell population could serve as a valuable marker of recurrence and poor prognosis in patients with locally advanced CRC. mSIA assessment after radical CRC resection may be promising for identifying high-risk patients with pT4 CRC who require aggressive adjuvant chemotherapy.
... 29 M2-associated CD163+ macrophages are a prognostic marker for BC and metastasis and an increased number of CD163+ macrophages are associated with decreased patient survival. [30][31][32] In contrast, higher levels of Significance statement • 2-methoxyestradiol (2-ME) is a synthetic oestrogen that has been shown to have antiproliferative and antiangiogenic effects in breast cancer (BC). ...
The prevalence of breast cancer (BC) continues to increase and is the leading cause of cancer deaths in many countries. Numerous in vitro and in vivo studies have demonstrated that 2-methoxyestradiol (2-ME) has antiproliferative and antiangiogenic effects in BC, thereby inhibiting tumour growth and metastasis. We compared the effect of 2-ME in early- and late-stage BC using a transgenic mouse model-FVB/N-Tg(MMTV-PyVT)-of spontaneously development of aggressive mammary carcinoma with lung metastasis. Mice received 100 mg/kg 2-ME treatment immediately when palpable mammary tumours were identified (early-stage BC; Experimental group 1) and 28 days after palpable mammary tumours were detected (late-stage BC; Experimental group 2). 2-ME was administered via oral gavage three times a week for 28 days after initiation of treatment, whereas control mice received the vehicle containing 10% dimethyl sulfoxide and 90% sunflower oil for the same duration as the treatment group. Mammary tumours were measured weekly over the 28 days and at termination, blood, mammary and lung tissue were collected for analysis. Mice with a tumour volume threshold of 4000 mm3 were killed before the treatment regime was completed. 2-ME treatment of early-stage BC led to lower levels of mammary tumour necrosis, whereas tumour mass and volume were increased. Additionally, necrotic lesions and anti-inflammatory CD163-expressing cells were more frequent in pulmonary metastatic tumours in this group. In contrast, 2-ME treatment of late-stage BC inhibited tumour growth over the 28-day period and resulted in increased CD3+ cell number and tumour necrosis. Furthermore, 2-ME treatment slowed down pulmonary metastasis but did not increase survival of late-stage BC mice. Besides late-stage tumour necrosis, none of the other results were statistically significant. This study demonstrates that 2-ME treatment has an antitumour effect on late-stage BC, however, with no increase in survival rate, whereas the treatment failed to demonstrate any benefit in early-stage BC.
... Macrophages have been investigated in various malignant cancer entities, such as ovarian tumors, pancreatic, rectal, and breast cancers [54][55][56][57]. Depending on the type of macrophages, they either provide defense against tumor cells (M1-type) or promote tumor cell proliferation (M2-type). ...
Simple Summary
This is the first study on the tumor microenvironment of uveal melanoma with special regard to the localization within the tumor and the eye. Uveal melanoma is the most common malignant tumor of the eye in adults. Regardless of the treatment of the primary tumor, half of the patients with uveal melanoma die due to metastasis in the long run. The major findings of this study are that blood vessels are mainly located in the middle of the tumor and that immune cells (especially CD68-immunopositive macrophages) are mostly found in the outer section of the tumor. Furthermore, this study found a high representation of lymphocyte activation gene-3 (LAG-3) and Galectin-3 in uveal melanoma. These findings could set a foundation for new therapeutic strategies aimed at improving the survival rate of patients with uveal melanoma.
Abstract
Uveal melanoma (UM) is a highly malignant tumor of the eye. Metastatic spread of UM occurs almost exclusively via blood vessels and is of tremendous interest, as half of the patients with uveal melanoma die of metastasis in the long run. The tumor microenvironment consists of all cellular and non-cellular compounds of a solid tumor, except for the tumor cells. This study aims to provide a more detailed understanding of the tumor microenvironment of UM to build the foundation for new therapeutic targets. Fluorescence immunohistochemistry was performed to examine the localization of various cell types in the tumor microenvironment in UM. Furthermore, the presence of LAG-3 and its ligands Galectine-3 and LSECtin was examined to evaluate the potential efficacy of immune checkpoint inhibitor-based therapies. The main findings are that blood vessels are mainly located in the middle of the tumor, and that immune cells are mostly found in the outer section of the tumor. LAG-3 and Galectine-3 were found to be highly represented, whereas LSECtin barely occurred in UM. Both the predominant location of tumor-associated macrophages in the outer section of the tumor and the high presence of LAG-3 and Galectine-3 in the UM serve as attainable therapeutic targets.
... BC cells secrete factors that differentiate macrophages toward the M2 phenotype [29]. M2-associated CD163 + macrophages are a prognostic marker for BC and metastasis and an increased number of CD163 + macrophages are associated with decreased patient survival [30][31][32]. In contrast, higher levels of CD3 + cells are associated with good prognosis biomarkers such as CD8 and CD20, and are associated with increased survival [33][34][35]. ...
BACKGROUND: The prevalence of breast cancer (BC) continues to increase and is the leading cause of cancer deaths in many countries. Numerous in vitro and in vivo studies have demonstrated that 2-methoxyestradiol (2-ME) has antiproliferative and antiangiogenic effects in BC thereby inhibiting tumour growth and metastasis. We compared the effect of 2-ME in early and late-stage BC using a transgenic mouse model – FVB/N-Tg(MMTV-PyVT) – of spontaneously development of aggressive mammary carcinoma with lung metastasis.
METHODS: Mice received 100 mg/kg 2-ME treatment immediately when palpable mammary tumours were identified (early-stage BC; experimental group 1) and 28 days after palpable mammary tumours were detected (late-stage BC; experimental group 2). 2-ME was administered via oral gavage three times a week for 28 days after initiation of treatment, while control mice received the vehicle containing 10% dimethyl sulfoxide (DMSO) and 90% sunflower oil for the same duration as the treatment group. Mammary tumours were measured weekly over the 28-day period and at termination, blood, mammary and lung tissue were collected for analysis. Mice with a tumour volume threshold of 4000mm³ were euthanized before the treatment regime was completed.
RESULTS: 2-ME treatment of early-stage BC led to lower levels of mammary tumour necrosis, while tumour mass and volume were increased. Additionally, necrotic lesions and anti-inflammatory CD163 expressing cells were more frequent in pulmonary metastatic tumours in this group. In contrast, 2-ME treatment of late-stage BC inhibited tumour growth over the 28-day period, and resulted in increased CD3+ cell number and tumour necrosis. Furthermore, 2-ME treatment slowed down pulmonary metastasis, but did not increase survival of late-stage BC mice. Besides late-stage tumour necrosis, none of the other results were statistically significant.
CONCLUSION: This study demonstrates that 2-ME treatment has an antitumour effect on late-stage BC, however with no increase in survival rate, while the treatment failed to demonstrate any benefit in early-stage BC.
... A high TAM density is associated with a poor prognosis in BC [47,48] and surface expression of CD163 correlates with tumor progression and worsened prognosis [48,49]. CD163 expression has been largely considered to be present only on the surface of the monocyte/macrophage lineage and has just recently been reported to be also expressed in some tumor cells characterized by an advanced histological grade, a higher occurrence of distant metastasis and reduced patient survival [50,51]. Our data in both BC cells/macrophage co-cultures and isolated macrophages strongly suggest PBA is a suppressor of the macrophage M2 polarization. ...
Simple Summary
Bladder cancer (BC) is the second most frequent cancer of the genitourinary system. More than 500,000 patients per year are diagnosed with BC, a disease which additionally results in more than 200,000 annual deaths. One of the major problems in BC treatment is that many patients cannot receive appropriate treatment due to comorbidities and the severe inflammatory side effects of therapy. The aim of our study was to assess the effect of butyrate derivatives, demonstrating that they could be beneficial for treating the tumor and also to modify the tumor microenvironment. Upon treatment with butyrate derivatives, we particularly saw increased PD-L1 surface expression and reduced pluripotency molecular markers in a hybrid BC–macrophage cell population. This is a cell population known to display an increased capacity to migrate and evade immunity. Treatment with butyrate derivatives may also provide a better chance of immunotherapy success for BC patients.
Abstract
Bladder cancer (BC) is the second most frequent cancer of the genitourinary system. The most successful therapy since the 1970s has consisted of intravesical instillations of Bacillus Calmette–Guérin (BCG) in which the tumor microenvironment (TME), including macrophages, plays an important role. However, some patients cannot be treated with this therapy due to comorbidities and severe inflammatory side effects. The overexpression of histone deacetylases (HDACs) in BC has been correlated with macrophage polarization together with higher tumor grades and poor prognosis. Herein we demonstrated that phenylbutyrate acid (PBA), a HDAC inhibitor, acts as an antitumoral compound and immunomodulator. In BC cell lines, PBA induced significant cell cycle arrest in G1, reduced stemness markers and increased PD-L1 expression with a corresponding reduction in histone 3 and 4 acetylation patterns. Concerning its role as an immunomodulator, we found that PBA reduced macrophage IL-6 and IL-10 production as well as CD14 downregulation and the upregulation of both PD-L1 and IL-1β. Along this line, PBA showed a reduction in IL-4-induced M2 polarization in human macrophages. In co-cultures of BC cell lines with human macrophages, a double-positive myeloid–tumoral hybrid population (CD11b⁺EPCAM⁺) was detected after 48 h, which indicates BC cell–macrophage fusions known as tumor hybrid cells (THC). These THC were characterized by high PD-L1 and stemness markers (SOX2, NANOG, miR-302) as compared with non-fused (CD11b⁻EPCAM⁺) cancer cells. Eventually, PBA reduced stemness markers along with BMP4 and IL-10. Our data indicate that PBA could have beneficial properties for BC management, affecting not only tumor cells but also the TME.
Simple Summary
This review summarizes the pivotal role of tumor-infiltrating immune cells (TIICs) within the tumor microenvironment (TME) and their impact on cancer prognosis and treatment response. By analyzing TIICs alongside tumor mutation burden (TMB) and immune checkpoint inhibitor (ICI) scores, this study reveals insights into cancer’s immune landscapes. Understanding TIICs’ influence enables tailored cancer treatments, aiding postoperative care, therapy decisions, and personalized medicine choices. We effectively examined the predictive and prognostic value of TIICs alongside TMB and ICI scores in identifying the diverse immunological environments of cancer. Several approaches discussed in this review provide more accurate predictions of patient outcomes and treatment responses. These models can help identify individuals who may derive greater benefit from adjuvant or neoadjuvant treatment. In summary, we believe that the major contribution of TIICs in cancer will have a substantial positive impact on postoperative follow-up, therapy, interventions, and the ability to make educated decisions regarding personalized cancer treatments. This comprehensive study underscores the significant role of TIICs in combating tumor-mediated immunosuppression and fostering antitumor immune responses, promising improved cancer prognosis and therapeutic outcomes.
Abstract
TIICs are critical components of the TME and are used to estimate prognostic and treatment responses in many malignancies. TIICs in the tumor microenvironment are assessed and quantified by categorizing immune cells into three subtypes: CD66b+ tumor-associated neutrophils (TANs), FoxP3+ regulatory T cells (Tregs), and CD163+ tumor-associated macrophages (TAMs). In addition, many cancers have tumor-infiltrating M1 and M2 macrophages, neutrophils (Neu), CD4+ T cells (T-helper), CD8+ T cells (T-cytotoxic), eosinophils, and mast cells. A variety of clinical treatments have linked tumor immune cell infiltration (ICI) to immunotherapy receptivity and prognosis. To improve the therapeutic effectiveness of immune-modulating drugs in a wider cancer patient population, immune cells and their interactions in the TME must be better understood. This study examines the clinicopathological effects of TIICs in overcoming tumor-mediated immunosuppression to boost antitumor immune responses and improve cancer prognosis. We successfully analyzed the predictive and prognostic usefulness of TIICs alongside TMB and ICI scores to identify cancer’s varied immune landscapes. Traditionally, immune cell infiltration was quantified using flow cytometry, immunohistochemistry, gene set enrichment analysis (GSEA), CIBERSORT, ESTIMATE, and other platforms that use integrated immune gene sets from previously published studies. We have also thoroughly examined traditional limitations and newly created unsupervised clustering and deconvolution techniques (SpatialVizScore and ProTICS). These methods predict patient outcomes and treatment responses better. These models may also identify individuals who may benefit more from adjuvant or neoadjuvant treatment. Overall, we think that the significant contribution of TIICs in cancer will greatly benefit postoperative follow-up, therapy, interventions, and informed choices on customized cancer medicines.
The natural phenomenon of cell–cell fusion does not only take place in physiological processes, such as placentation, myogenesis, or osteoclastogenesis, but also in pathophysiological processes, such as cancer. More than a century ago postulated, today the hypothesis that the fusion of cancer cells with normal cells leads to the formation of cancer hybrid cells with altered properties is in scientific consensus. Some studies that have investigated the mechanisms and conditions for the fusion of cancer cells with other cells, as well as studies that have characterized the resulting cancer hybrid cells, are presented in this review. Hypoxia and the cytokine TNFα, for example, have been found to promote cell fusion. In addition, it has been found that both the protein Syncytin-1, which normally plays a role in placentation, and phosphatidylserine signaling on the cell membrane are involved in the fusion of cancer cells with other cells. In human cancer, cancer hybrid cells were detected not only in the primary tumor, but also in the circulation of patients as so-called circulating hybrid cells, where they often correlated with a worse outcome. Although some data are available, the questions of how and especially why cancer cells fuse with other cells are still not fully answered.
IntroductionWhile most patients with triple negative breast cancer receive radiation therapy to improve outcomes, a significant subset of patients continue to experience recurrence. Macrophage infiltration into radiation-damaged sites has been shown to promote breast cancer recurrence in pre-clinical models. However, the mechanisms that drive recurrence are unknown. Here, we developed a novel spheroid model to evaluate macrophage-mediated tumor cell recruitment.Methods
We characterized infiltrating macrophage phenotypes into irradiated mouse mammary tissue via flow cytometry. We then engineered a spheroid model of radiation damage with primary fibroblasts, macrophages, and 4T1 mouse mammary carcinoma cells using in vivo macrophage infiltration results to inform our model. We analyzed 4T1 infiltration into spheroids when co-cultured with biologically relevant ratios of pro-healing M2:pro-inflammatory M1 macrophages. Finally, we quantified interleukin 6 (IL-6) secretion associated with conditions favorable to tumor cell infiltration, and we directly evaluated the impact of IL-6 on tumor cell invasiveness in vitro and in vivo.ResultsIn our in vivo model, we observed a significant increase in M2 macrophages in mouse mammary glands 10 days post-irradiation. We determined that tumor cell motility toward irradiated spheroids was enhanced in the presence of a 2:1 ratio of M2:M1 macrophages. We also measured a significant increase in IL-6 secretion after irradiation both in vivo and in our model. This secretion increased tumor cell invasiveness, and tumor cell invasion and recruitment were mitigated by neutralizing IL-6.Conclusions
Our work suggests that interactions between infiltrating macrophages and damaged stromal cells facilitate breast cancer recurrence through IL-6 signaling.
Cancer Genes is a comprehensive list of the most critical genes known to contribute to cancer imitation and progression. The book delves into their location on each chromosome, providing valuable insights into the mechanisms of cancer gene dysregulation and genetic mutations which provide cancer cells with an advantage during each stage of tumorigenesis. The reference will familiarize readers with the location of cancer genes and equip them with the necessary information to identify relevant gene expression targets for research aimed at preventing the disease.
The book is divided into two volumes focusing on cancer-causing genes found in chromosome pairs 1-12 (volume 1), and chromosomes 13-23 (volume 2). A key features of the book is a detailed reference list for advanced readers. The compilation is therefore a quick and handy reference on cancer causing genes for researchers, medical professionals, and anyone interested in understanding the genetic basis of cancer.
Every cancer genome is unique, resulting in potentially near infinite cancer cell phenotypes and an inability to predict clinical outcomes in most cases. Despite this profound genomic heterogeneity, many cancer types and subtypes display a non-random distribution of metastasis to distant organs, a phenomenon known as organotropism. Proposed factors in metastatic organotropism include hematogenous versus lymphatic dissemination, the circulation pattern of the tissue of origin, tumor-intrinsic factors, compatibility with established organ-specific niches, long-range induction of premetastatic niche formation, and so-called “prometastatic niches” that facilitate successful colonization of the secondary site following extravasation. To successfully complete the steps required for distant metastasis, cancer cells must evade immunosurveillance and survive in multiple new and hostile environments. Despite substantial advances in our understanding of the biology underlying malignancy, many of the mechanisms used by cancer cells to survive the metastatic journey remain a mystery. This review synthesizes the rapidly growing body of literature demonstrating the relevance of an unusual cell type known as “fusion hybrid” cells to many of the hallmarks of cancer, including tumor heterogeneity, metastatic conversion, survival in circulation, and metastatic organotropism. Whereas the concept of fusion between tumor cells and blood cells was initially proposed over a century ago, only recently have technological advancements allowed for detection of cells containing components of both immune and neoplastic cells within primary and metastatic lesions as well as among circulating malignant cells. Specifically, heterotypic fusion of cancer cells with monocytes and macrophages results in a highly heterogeneous population of hybrid daughter cells with enhanced malignant potential. Proposed mechanisms behind these findings include rapid, massive genome rearrangement during nuclear fusion and/or acquisition of monocyte/macrophage features such as migratory and invasive capability, immune privilege, immune cell trafficking and homing, and others. Rapid acquisition of these cellular traits may increase the likelihood of both escape from the primary tumor site and extravasation of hybrid cells at a secondary location that is amenable to colonization by that particular hybrid phenotype, providing a partial explanation for the patterns observed in some cancers with regard to sites of distant metastases.
With its lack of commonly targeted receptors, triple negative breast cancer (TNBC) is aggressive and difficult to treat. To address this problem, nanotubes self-assembled from single stranded DNA (ssDNA)-amphiphiles were used as a delivery vehicle for doxorubicin (DOX) to target TNBC cells. Since DOX and other standard of care treatments such as radiation have been documented to induce senescence, the ability of the nanotubes to deliver the senolytic ABT-263 was also investigated. The ssDNA-amphiphiles were synthesized from a 10 nucleotide sequence attached to a dialkyl, (C16)2, tail via a C12 alkyl spacer, and have been previously shown to self-assemble into hollow nanotubes and spherical micelles. Here, we demontrate that these ssDNA spherical micelles could transition into long nanotubes in the presence of excess tails. The nanotubes could then be shortened via probe sonication. The ssDNA nanotubes internalized into three different TNBC cell lines: Sum159, MDA-MB-231, and BT549, with minimal internalization in healthy Hs578Bst cells, suggesting an inherent targeting ability. Inhibition of different internalization mechanisms showed that the nanotubes internalized in the TNBC cells primarily through macropinocytosis and scavenger receptor-mediated endocytosis, both of which are upregulated pathways in TNBC. DOX was intercalated into the ssDNA nanotubes and delivered to TNBC cells. Compared to free DOX, DOX-intercalated nanotubes proved equally cytotoxic to TNBC cells. In order to demonstrate the potential for delivery of different therapeutics, ABT-263 was incorporated into the hydrophobic bilayer wall of the nanotubes and was delivered to a DOX-induced in vitro model of senescence. The ABT-263 encapsulating nanotubes demonstrated cytotoxicity to senescent TNBC cells as well as sensitization to further DOX treatment. Thus, our ssDNA nanotubes are a promising delivery vehicle that could be used for targeted delivery of therapeutics to TNBC cells.
CRCMSS/pMMR contain a significantly increased fraction of TREM2+ macrophages (TAMs) and CD66+ neutrophils (TANs) together with decrease of CD4-CD8-CD3+ double negative T lymphocytes (DNTs); no differences were revealed by the analysis of myeloid and plasmacytoid dendritic cell populations. A fraction of tumor-infiltrating T-cells display an exhausted phenotype, co-expressing PD-1 and TIM-3. Remarkably, expression of PD-L1 on fresh tumor cells and TAMs was undetectable even after in vitro stimulation with interferon-γ. These findings confirm the immune suppressive microenvironment of CRCMSS/pMMR characterized by dense infiltration of TAMs, occurrence of TANs, lack of DNTs, T-cell exhaustion and interferon-γ unresponsiveness by host and tumor cells. Appropriate bypass strategies should consider these combinations of immune escape mechanisms in CRCMSS/pMMR.
Adaptor proteins represent key signalling molecules involved in regulating immune responses. The host's innate immune system recognizes pathogens via various surface and intracellular receptors. Adaptor molecules are centrally involved in different receptor-mediated signalling pathways, acting as bridges between the receptors and other molecules. The presence of adaptors in major signalling pathways involved in the pathogenesis of various chronic inflammatory diseases has drawn attention toward the role of these proteins in such diseases. In this review, we summarize the importance and roles of different adaptor molecules in macrophage-mediated signalling in various chronic disease states. We highlight the mechanistic roles of adaptors and how they are involved in protein-protein interactions (PPI) via different domains to carry out signalling. Hence, we also provide insights into how targeting these adaptor proteins can be a good therapeutic strategy against various chronic inflammatory diseases.
Single-agent immune checkpoint blockade has shown no clinical benefits in pancreatic cancer. Recently, the programmed cell death protein 1 (PD-1) antibody pembrolizumab has been recommended as a treatment option for high tumor mutational burden (TMB) solid tumors based on the data from a basket trial. However, no pancreatic cancer patients were enrolled in that trial. Whether pancreatic cancer patients with high TMB respond to PD-1 blockade as well remains unclear. Here, we report a case with a partial response to single-agent immunotherapy with pembrolizumab in pancreatic cancer with high TMB after the failure of several lines of chemotherapy. This result indicates that single-agent immunotherapy may be effective in pancreatic cancer patients with high TMB. In addition, in order to understand the basic immune state of our patients, we also analyzed the changes in immune cells in peripheral blood with cytometry by time-of-flight mass spectrometry (CyTOF) before and after pembrolizumab treatment.
Introduction:
Tumor-associated macrophages (TAMs) in breast cancer are associated with a poor prognosis. Early studies of TAMs were largely limited to the pan-macrophage marker CD68, however, more recently, an increasing number of studies have used CD163, a marker expressed by alternatively activated M2 macrophages and TAM subsets. We hypothesized that CD163-positive (CD163+) TAMs would be a better predictor of survival outcomes in breast cancer compared to CD68+ TAMs.
Methods:
We performed a systematic literature search of trials (from 1900 to August 2020) reporting overall survival (OS) or progression-free survival (PFS), breast cancer-specific survival (BCSS), TAM phenotype, and density. Thirty-two studies with 8446 patients were included. Meta-analyses were carried out on hazard ratios (HRs) for survival outcomes of breast cancer patients with a high density of TAMs (CD68+ and/or CD163+) compared to a low density of TAMs.
Results:
A high density of TAMs (CD68+ and/or CD163+) was associated with decreased OS (HR 1.69, 95% CI 1.37-2.07) and reduced PFS (HR 1.64; 95% CI 1.35-1.99). Subgrouping by CD marker type showed a lower OS for high density of CD163+ TAMs (HR 2.24; 95% CI 1.71-2.92) compared to a high density of CD68+ TAMs (HR 1.5; 95% CI 1.12-2). A high density of TAMs (CD68+ and/or CD163+) in triple-negative breast cancer (TNBC) cases was associated with lower OS (HR 2.81, 95% CI 1.35-5.84).
Conclusion:
Compared to CD68+ TAMs, a high density of CD163+ TAMs that express a similar phenotype to M2 macrophages are a better predictor of poor survival outcomes in breast cancer.
Heterotypic interaction between tumor cells and adjacent stromal cells mediates tumor development. However, how tumor heterogeneity commits tumors to the malignant transformation and evasion of immunity against metastasis is poorly understood. Here, we have investigated the fusogenicity of human invasive glioblastoma, triple negative breast cancer and gallbladder cancer cells that are all characterized by mesenchymal cell plasticity. These cells displayed the rigorous ability to fuse with macrophages and augment epithelial-mesenchymal transition (EMT), transforming the fused cells into highly invasive hybrids. YKL-40 (Chitinase-3-like-1), known to promote inflammation and serve as an EMT marker, was essential and sufficient for both cell fusion and the invasiveness of tumor cells that express EMT and tumor-associated macrophage markers. Intriguingly, differential gene profiling of single clones from the hybrids demonstrated that YKL-40 and immune checkpoint protein B7-2 (CD86) were elevated and functioned to independently suppress anti-tumor immune factor levels of CD8 ⁺ -cytotoxic T lymphocytes (CTL); thus resulting in escape of immune surveillance. YKL-40 and B7-2 dual shRNA abrogated YKL-40-mediated cell fusion and restored CTL anti-tumor immunity, compromising tumor development in xenografts. Clinically, we found tumor hybrids were present in mesenchymal types of glioblastomas, gallbladder cancer and breast cancer. In addition, YKL-40 expression in glioblastoma was correlated with decreased disease-free survival in patients. Collectively, these data offer novel cellular and molecular mechanisms underpinning immune evasion and tumor malignancy, and suggest a new immunotherapeutic intervention strategy by targeting both YKL-40 and B7-2 in cancer.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
With over 200 types of cancer diagnosed to date, researchers the world over have been forced to rapidly update their understanding of the biology of cancer. In fact, only the study of the basic cellular processes, and how these are altered in cancer cells, can ultimately provide a background for rational therapies. Bringing together the state-of-the-art contributions of international experts, Systems Biology of Cancer proposes an ultimate research goal for the whole scientific community: exploiting systems biology to generate in-depth knowledge based on blueprints that are unique to each type of cancer. Readers are provided with a realistic view of what is known and what is yet to be uncovered on the aberrations in the fundamental biological processes, deregulation of major signaling networks, alterations in major cancers and the strategies for using the scientific knowledge for effective diagnosis, prognosis and drug discovery to improve public health.
Background:
Extramural vascular invasion (EMVI) is a known poor prognostic factor in colorectal carcinoma; however, its molecular basis has not been defined. This study aimed to assess the expression of molecular markers in EMVI positive colorectal carcinoma to understand their tumor microenvironment.
Methods:
Immunohistochemistry was performed on tissue microarrays of surgically resected colorectal cancer specimens for immunological markers, and BRAFV600E mutation (and on the tissue blocks for mismatch repair proteins). Automated quantification was used for CD8, LAG3, FOXP3, PU1, and CD163, and manual quantification was used for PDL1, HLA I markers (beta-2 microglobulin, HC10), and HLA II. The Wilcoxon rank-sum test was used to compare EMVI positive and negative tumors. A logistic regression model was fitted to assess the predictive effect of biomarkers on EMVI.
Results:
There were 340 EMVI positive and 678 EMVI negative chemo naïve tumors. PDL1 was barely expressed on tumor cells (median 0) in the entire cohort. We found a significantly lower expression of CD8, LAG3, FOXP3, PU1 cells, PDL1 positive macrophages, and beta-2 microglobulin on tumor cells in the EMVI positive subset (p ≤ 0.001). There was no association of BRAFV600E or deficient mismatch repair proteins (dMMR) with EMVI. PU1 (OR 0.8, 0.7-0.9) and low PDL1 (OR 1.6, 1.1-2.3) independently predicted EMVI on multivariate logistic regression among all biomarkers examined.
Conclusion:
There is a generalized blunting of immune response in EMVI positive colorectal carcinoma, which may contribute to a worse prognosis. Tumor-associated macrophages seem to play the most significant role in determining EMVI.
Tumor-associated macrophages (TAMs) are a promising therapeutic target for cancers, but achieving multitarget therapy of TAMs is still challenging. Here, we develop a protein-crowned micelle system for targeted and synergistic TAM reprogramming to enhance cancer treatment. The doxorubicin-loaded micelles with a hemoglobin crown (Hb-DOXM) can bind with endogenous plasma haptoglobin to realize specific M2-type TAM targeting. Under the tumor hypoxic and acidic environments, Hb-DOXM can responsively release O2 and DOX to reduce the recruitment of TAMs by hypoxia remission and release DOX to kill M2-type TAMs and cancer cells. To reprogram TAMs adequately, the TAM-modulating drug celecoxib is further encapsulated (Hb-DOXM@Cel) to repolarize M2-type TAMs. The targeted and synergistic TAM reprogramming by Hb-DOXM@Cel can remodel the tumor microenvironment (TME) to an immunostimulatory microenvironment and augment the antitumor effect of cytotoxic T lymphocyte, thus strongly enhancing the DOX-based chemotherapy. The protein-crowned micelle strategy presents a targeted and synergistic TAM therapy tool for enhanced cancer treatment.
CS/ICs have raised great expectations in cancer research and therapy, as eradication of this key cancer cell type is expected to lead to a complete cure. Unfortunately, the biology of CS/ICs is rather complex, since no common CS/IC marker has yet been identified. Certain surface markers or ALDH1 expression can be used for detection, but some studies indicated that cancer cells exhibit a certain plasticity, so CS/ICs can also arise from non-CS/ICs. Another problem is intratumoral heterogeneity, from which it can be inferred that different CS/IC subclones must be present in the tumor. Cell–cell fusion between cancer cells and normal cells, such as macrophages and stem cells, has been associated with the generation of tumor hybrids that can exhibit novel properties, such as an enhanced metastatic capacity and even CS/IC properties. Moreover, cell–cell fusion is a complex process in which parental chromosomes are mixed and randomly distributed among daughter cells, resulting in multiple, unique tumor hybrids. These, if they have CS/IC properties, may contribute to the heterogeneity of the CS/IC pool. In this review, we will discuss whether cell–cell fusion could also lead to the origin of different CS/ICs that may expand the overall CS/IC pool in a primary tumor.
Summary Interleukin-10 (IL-10) is a recently described pteiotropic cytokine secreted mainly by type 2 helper T cells. Previous studies have shown that IL-t0 suppresses cytokine expression by natu- ral killer (NK) and type 1 T cells, thus down-regulating cell-mediated immunity and stimulat- ing humoral responses. We here report that injected IL-t0 protein is an efficient inhibitor of tumor metastasis in experimental (B16-F10) and spontaneous (M27 and Lox human mela- noma) metastasis models in vivo at doses that do not have toxic effects on normal or cancer cells. Histological characterization after IL-10 treatment confirmed the absence of CD8 + and CD4 + T cells and macrophages at the sites of tumor growth, but abundant NK cells were lo- calized at these sites. This unexpected finding was confirmed by showing that IL-10 inhibits most B16-F10 and Lox metastases in mice deficient in T or B cells (SCID and nu/nu mice), but not in those deficient in NK cells (beige mice or NK cell--depleted mice). However, IL-t0 downregulation of pro-inflammatory cytokine production and/or recruitment of additional ef- f~ctor cells may also be involved in the anti-tumor effect at higher local concentrations of IL-t0, since transfected B16 tumor cells expressing high amounts of lL-10 were rejected by normal, nu/nu, or SCID mice at the primary tumor stage, and there was still a 33% inhibition of tumor metastasis in beige mice.
It has been demonstrated that γδ T cells accumulating in early tumor lesions and those purified from spleen cells of tumor-bearing mice attenuate the activity of CTLs and NK cells. We, therefore, investigated whether depletion of γδ T cells from early lesions of tumors results in restoration of CTL and NK cell activities and subsequent regression of tumors. A daunomycin-conjugated anti-γδTCR mAb UC7-13D5 (Dau-UC7) was prepared to efficiently deplete γδ T cells. An in vitro study revealed that Dau-UC7 specifically lysed γδTCR+ cells and effectively inhibited splenic γδ T cells from tumor-bearing mice to produce cytotoxic cell-suppressive factors. Furthermore, intralesional injections of Dau-UC7 at an early stage of tumor development led to augmentation of tumor-specific CTL as well as NK cell activities and to the resultant regression or growth inhibition of the tumors. On analysis of cytokine profile, γδ T cells transcribed mRNAs for IL-10 and TGF-β, but not IL-4 or IFN-γ, suggesting the T regulatory 1-like phenotype. Finally, a blocking study with mAbs showed that the inhibitory action of γδ T cells on CTLs and NK cells was at least partly mediated by IL-10 and TGF-β. These results clearly demonstrated the novel mechanism by which T regulatory 1-like γδ T cells suppress anti-tumor CTL and NK activities by their regulatory cytokines in early tumor formation.
CD163 is a glucocorticoid-inducible member of the scavenger receptor cysteine-rich family of proteins. Previous reports have indicated that CD163 is highly expressed on human macrophages, but found on less than 50% of peripheral blood monocytes. We now show that >99% of all CD14 positive monocytes express CD163 and that monocyte derived dendritic cells express low levels of CD163. We also show that IL-10, like glucocorticoids, induces high CD163 expression on cultured human monocytes. Glucocorticoid induced CD163 expression was not inhibited by anti-IL-10 and was additive with IL-10 treatment, suggesting that glucocorticoids increase CD163 expression by an IL-10 independent mechanism. Other anti-inflammatory cytokines (IL-4 and IL-13) did not increase CD163 expression. In addition, we show that p155 (a previously identified monocyte/macrophage marker of unknown function) shares identity with CD163. Western blots and flow cytometric analysis of HEK 293 cells transfected with the cDNA for CD163 were positive when probed with either mAb RM3/1 (which recognizes CD163) or Mac 2-48 (which defines p155).
The murine monoclonal antibody Mac 387 was raised against a purified protein fraction obtained from human monocytes. By immunoblotting experiments, Mac 387 was shown to react with a previously defined antigen called L1; this is a multichain myelomoncytic protein of about 36 Kd which shows sequence homology with the cystic fibrosis antigen. The L1 protein is present in the cytoplasm of virtually all resting peripheral neutrophils and monocytes; it is also variably expressed on the plasma membrane of these cells, possibly as a secretory product. Because the L1 antigen is resistant to denaturation by formalin, its tissue distribution can be studied in routinely processed biopsy material. In a wide variety of specimens Mac 387 was shown by immunohistochemical analysis, to produce a cytoplasmic staining pattern concordant with that of a well defined polyclonal antibody to the L1 antigen. Cytoplasmic reactivity was obtained with granulocytes and infiltrating macrophages but generally not with several categories of dendritic cells. In addition, squamous epithelium of mucous membranes was strongly positive, in contrast to normal epidermis.
A low metastatic, thioguanine-resistant murine T lymphoma line (EbTGR) was hybridized in vitro, with the help of polyethylene glycol, with syngeneic bone marrow-derived macrophages. Two HAT-resistant hybrid lines (Eb-F1 and Eb-F2) were obtained from independent fusion cultures. A cytogenetic analysis revealed that most of the macrophage chromosomes except No. 12 had segregated or become rearranged 60 d after fusion, a time at which the cell lines had become stabilized in culture. Syngeneic mice inoculated subcutaneously with the tumor macrophage hybrid lines developed, very quickly, visceral metastases and died after less than 2 wk, while those inoculated with the parental line lived for greater than 6 wk and developed only localized, large primary tumors. The metastatic hybridomas expressed a similar tumor antigen as a spontaneous, in vivo derived, high metastatic variant (ESb) of the same tumor. This suggests that ESb cells might have arisen from a spontaneous fusion with a host macrophage.
Several observations correlate increased expression of transforming growth factor (TGF) beta 1 with tumorigenesis, suggesting that expression of this multifunctional growth factor may provide an advantage in tumor formation. However, many tumor cells are inhibited in their proliferation by TGF-beta in vitro, thus suggesting that TGF-beta synthesis could exert an antiproliferative effect on tumor formation. To evaluate the physiological relevance of increased TGF-beta 1 synthesis in such tumor cells which are strongly inhibited in their proliferation by TGF-beta, we chose Meth A sarcoma cells as a model system. We established cell clones overexpressing TGF-beta 1 and determined its effect on tumor formation in mice that are not immunocompromised. Increased expression of biologically active TGF-beta 1 resulted in a profound growth inhibition in the transfected clones and increased adhesiveness in vitro. However, these cells were much more tumorigenic than Meth A cells that did not overexpress TGF-beta 1, as assessed by both tumor incidence and tumor growth. In addition, parental Meth A cells were inhibited in their tumor formation by neutralizing TGF-beta antibodies and stimulated by exogenous TGF-beta. Our results thus provide evidence that increased TGF-beta synthesis provides a major advantage for tumorigenesis, even if the cells are growth inhibited by their endogenous TGF-beta synthesis in culture. These results suggest that, in vivo, direct effects of TGF-beta on the tumor environment, such as increased extracellular matrix formation and cell-matrix interactions, and local suppression of the immune surveillance may provide a growth advantage which overrules any direct antiproliferative effects of TGF-beta, as suggested by the effects in culture.
Interleukin 10 (IL-10) is a potent immunoregulatory cytokine. It inhibits some cell functions, including T-helper (Th1) cell activity (i.e., interleukin 2 and interferon gamma production), and stimulates other functions such as a natural killer (NK) activity. In mice, IL-10 suppresses tumorigenicity in a xenograft system using a nonmetastasizing hamster cell line.
We evaluated the antitumor and antimetastatic properties of IL-10 in syngeneic immunocompetent and immunocompromised murine hosts.
Using the plasmids pBMGneo and pBMGneo.IL-10, we transfected the highly malignant murine mammary tumor cell lines 410.4 and 66.1 (transfectants designated as 410.4-IL10 and 66.1-IL10, respectively) to stably express IL-10 (2-100 U IL-10/2.5 x 10(5) cells per 48 hours). Tumorigenic and metastatic activities of the parent and transfected cells w ere measured in immunocompetent, syngeneic BALB/cByJ mice as well as in immunocompromised C.B-17/IcrCrl-SCID/Beige mice.
Tumor growth was completely inhibited following inoculations of 5 x 10(6)410.4-IL10 cells in immunocompetent, syngeneic BALB/cByJ mice. This inoculum contains 100 times the minimum cell number required for 100% tumor incidence. In contrast, tumor growth following the inoculation of parental 410.4 or 410.4-neo cells was progressive, resulting in death of animals from pulmonary metastases at days 40-50 and transplantation. The tumorigenicity of 66.1-IL-10, compared with that of its parent cell line, was also significantly abrogated by IL-10 expression. Furthermore, in immunocompetent mice, the metastatic potential of both 410.4-IL10 and 66.1-IL10 was also completely inhibited. In immunocompromised C.B-17/IcrCrl-SCID/BR or C.B-17/IcrCrl-SCID/Beige mice, subcutaneous implants of 410.4-IL10 grew progressively, but growth was inhibited significantly in comparison to that produced by the parental 410.4 or 410.4-neo cells. In spite of the more limited efficacy of IL-10 against tumor growth in immunocompromised mice, spontaneous metastasis of 410.4-IL10 cells in C.B-17/IcrCrl-SCID/BR mice was inhibited by 90%. When NK activity was suppressed by asialoGM1 ganglioside antibody in BALB/cByJ mice or in C.B-17/IcrCrl-SCID/Beige mice, the antimetastatic effect of IL-10 was lost.
These data show for the first time that IL-10 is a potent antimetastatic agent that is effective in immunocompromised hosts. This effect thus appears to be relatively independent of T-cell function but is dependent on NK activity. In contrast, the inhibitory effect of IL-10 on tumorigenicity relies on T-cell function.
Based on the recent observation of others that IL-10 has little toxicity when administered systemically to human volunteers and also on the findings of this study that it has antitumor and antimetastitic properties in mice, possible use of IL-10 in the treatment of human metastatic cancers deserves consideration.
Interleukin-10 (IL-10) is a recently described pleiotropic cytokine secreted mainly by type 2 helper T cells. Previous studies have shown that IL-10 suppresses cytokine expression by natural killer (NK) and type 1 T cells, thus down-regulating cell-mediated immunity and stimulating humoral responses. We here report that injected IL-10 protein is an efficient inhibitor of tumor metastasis in experimental (B16-F10) and spontaneous (M27 and Lox human melanoma) metastasis models in vivo at doses that do not have toxic effects on normal or cancer cells. Histological characterization after IL-10 treatment confirmed the absence of CD8+ and CD4+ T cells and macrophages at the sites of tumor growth, but abundant NK cells were localized at these sites. This unexpected finding was confirmed by showing that IL-10 inhibits most B16-F10 and Lox metastases in mice deficient in T or B cells (SCID and nu/nu mice), but not in those deficient in NK cells (beige mice or NK cell-depleted mice). However, IL-10 downregulation of pro-inflammatory cytokine production and/or recruitment of additional effector cells may also be involved in the anti-tumor effect at higher local concentrations of IL-10, since transfected B16 tumor cells expressing high amounts of IL-10 were rejected by normal, nu/nu, or SCID mice at the primary tumor stage, and there was still a 33% inhibition of tumor metastasis in beige mice.
CD163, also referred to as M130, a member of the scavenger receptor cysteine-rich family (SRCR) is exclusively expressed on cells of the monocyte lineage. In freshly isolated monocytes the CD14bright CD16+ monocyte subset revealed the highest expression of CD163 among all monocyte subsets. CD163 mRNA and protein expression is up-regulated during macrophage colony-stimulating factor (M-CSF)-dependent phagocytic differentiation of human blood monocytes. In contrast, monocytic cells treated with GM-CSF and interleukin-4 (IL-4) for dendritic differentiation down-regulate this antigen. CD163 expression is also suppressed by proinflammatory mediators like lipopolysaccharide (LPS), interferon-gamma (IFN-gamma), and tumor necrosis factor alpha, whereas IL-6 and the antiinflammatory cytokine interleukin-10 (IL-10) strongly up-regulate CD163 mRNA in monocytes and macrophages. The effects of the immunosuppressants dexamethasone, cyclosporin A (CA), and cortisol differ in their capacity to influence CD163 mRNA levels. Our results demonstrate that CD163 expression in monocytes/macrophages is regulated by proinflammatory and antiinflammatory mediators. This expression pattern implies a functional role of CD 163 in the antiinflammatory response of monocytes.
Intravascular haemolysis is a physiological phenomenon as well as a severe pathological complication when accelerated in various autoimmune, infectious (such as malaria) and inherited (such as sickle cell disease) disorders. Haemoglobin released into plasma is captured by the acute phase protein haptoglobin, which is depleted from plasma during elevated haemolysis. Here we report the identification of the acute phase-regulated and signal-inducing macrophage protein, CD163, as a receptor that scavenges haemoglobin by mediating endocytosis of haptoglobin-haemoglobin complexes. CD163 binds only haptoglobin and haemoglobin in complex, which indicates the exposure of a receptor-binding neoepitope. The receptor-ligand interaction is Ca2+-dependent and of high affinity. Complexes of haemoglobin and multimeric haptoglobin (the 2-2 phenotype) exhibit higher functional affinity for CD 163 than do complexes of haemoglobin and dimeric haptoglobin (the 1-1 phenotype). Specific CD163-mediated endocytosis of haptoglobin-haemoglobin complexes is measurable in cells transfected with CD163 complementary DNA and in CD163-expressing myelo-monocytic lymphoma cells.
Throughout the entire process of cancer aetiology, progression and metastasis, the microenvironment of the local host tissue can be an active participant. Invasion occurs within a tumour-host microecology, where stroma and tumour cells exchange enzymes and cytokines that modify the local extracellular matrix, stimulate migration, and promote proliferation and survival. A new class of cancer therapies that targets this pathological communication interface between tumour cells and host cells is currently under development.
Transforming growth factor-beta1 (TGF-beta1) produced by infiltrating macrophages plays a role in fibrotic disorders through the induction of myofibroblasts. To explore possible mechanisms by which TGF-beta1 may act in this context, we investigated effects of TGF-beta1 on macrophage-like (HS-P) and myofibroblastic (MT-9) cells, two novel cell lines developed by us. Immunocytochemically, the addition of TGF-beta1 (0, 0.1, 0.5, and 1.0 ng/ml) dose-dependently suppressed the expressions of antigens recognized by macrophage/histiocyte-specific antibodies (ED1 and ED2) in HS-P cells, whereas the addition concomitantly increased the number of anti-alpha-smooth muscle actin antibody-positive myofibroblastic cells, suggesting a possible phenotypical modulation of macrophages into myofibroblasts in the fibrotic lesions. By contrast, MT-9 cells did not show such immunophenotypical changes following TGF-beta1 addition. DNA synthesis, measured by tritiated thymidine-incorporation, was inhibited in a dose-dependent manner in MT-9 cells by TGF-beta1 addition (0, 0.1, 0.2, 0.5, 1.0, 5, and 10 ng/ml), but that in HS-P cells was unchanged. Northern blot analysis revealed that expressions of cell cycle-related early genes, c-jun and c-myc, were increased in HS-P cells after TGF-beta1 (1 ng/ml) addition, with c-jun showing peak expression prior to c-myc. By contrast, the peak expressions of c-jun and c-myc were delayed in TGF-beta1 (1 ng/ml)-added MT-9 cells, and their levels were less in MT-9 cells than in HS-P cells. Furthermore, TGF-beta1 (1 and 10 ng/ml) induced DNA laddering in MT-9 cells, but did not in HS-P cells. Based on these findings, it was speculated that TGF-beta1 could have induced G1 arrest in cell cycle and apoptosis in MT-9 cells. The present study showed that there were significant differences in the effects of TGF-beta1 between macrophage-like HS-P cells and myofibroblastic MT-9 cells, presumably depending on divergent susceptibilities to TGF-beta1 between both cell types. Because such cell types are key cells in the fibrogenesis, HS-P and MT-9 might be useful models for investigating the pathogenesis of fibrosis in vitro.
The c-Met tyrosine kinase receptor and its ligand, Hepatocyte Growth Factor/ Scatter Factor, have been implicated in human cancer. We have previously described that the transgenic expression of a truncated form of human c-Met (cyto-Met) in the liver confers resistance to several apoptotic stimuli. Here we show the impact of cyto-Met expression on liver proliferation and transformation. Despite a sixfold increase of hepatocyte proliferation, adult transgenic livers displayed normal size and architecture. We present evidence showing that activation of TGF-beta1 signalling controls the liver mass in cyto-Met mice. The oncogenic potential of cyto-Met was further assessed in the context of c-Myc-induced hepatocarcinogenesis, using WHV/c-Myc transgenic mice. Co-expression of cyto-Met and c-Myc further enhanced hepatocyte proliferation and caused a dramatic acceleration of the Myc-induced tumorigenesis, leading to the emergence of hepatocarcinomas in 3-4-month-old animals. Importantly, the TGF-beta receptor type II expression was strongly downregulated in most tumours, indicating that impairment of TGF-beta1-mediated growth inhibition plays a major role in accelerated neoplastic development. The strong potential of cyto-Met for oncogenic cooperation without direct transforming activity designates cyto-Met mice as an ideal tool for studying the early steps of multistage hepatocarcinogenesis and for identification of prognostic markers of transformation.
Recent studies have demonstrated that transplanted bone marrow cells can turn into unexpected lineages including myocytes, hepatocytes, neurons and many others. A potential problem, however, is that reports discussing such 'transdifferentiation' in vivo tend to conclude donor origin of transdifferentiated cells on the basis of the existence of donor-specific genes such as Y-chromosome markers. Here we demonstrate that mouse bone marrow cells can fuse spontaneously with embryonic stem cells in culture in vitro that contains interleukin-3. Moreover, spontaneously fused bone marrow cells can subsequently adopt the phenotype of the recipient cells, which, without detailed genetic analysis, might be interpreted as 'dedifferentiation' or transdifferentiation.
Regulatory T cells engage in the maintenance of immunological self-tolerance by actively suppressing self-reactive lymphocytes. Little is known, however, about the molecular mechanism of their development. Here we show that Foxp3, which encodes a transcription factor that is genetically defective in an autoimmune and inflammatory syndrome in humans and mice, is specifically expressed in naturally arising CD4+ regulatory T cells. Furthermore, retroviral gene transfer of Foxp3 converts naïve T cells toward a regulatory T cell phenotype similar to that of naturally occurring CD4+ regulatory T cells. Thus, Foxp3 is a key regulatory gene for the development of regulatory T cells.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.
The recent findings that cell fusion may be involved in stem cell differentiation (Medvinsky and Smith, 2003) raise a possibility that cell fusion has undiscovered functions, some of which can perhaps be found by revisiting the old ideas that cell fusion can promote disease, especially cancer.
Cell fusion is a process in which two or more cells become one by merging their plasma membranes. The ability of a cell to fuse to other cells is referred to as fusogenicity. The progeny of cell fusion are known as hybrids. Perhaps the best-known hybrids are hybridomas, which are made by fusing myeloma cells with lymphocytes to produce monoclonal antibodies. Although cells can be easily fused in the laboratory using readily available chemicals, cell fusion in live organisms appears to be a complex, poorly understood, multistep process that involves cell-cell recognition, cell adhesion, and membrane fusion (reviewed in Hernandez et al., 1996).
Transforming growth factor (TGF)-beta is a potent multifunctional cytokine that is an essential regulator of epithelial proliferation. Because TGF-beta is expressed almost entirely in a latent state in vivo, a major source of regulation of TGF-beta function is its activation. A subset of integrins, alphavbeta8 and alphavbeta6, which are expressed in the human airway, has recently been shown to activate latent TGF-beta in vitro, suggesting a regulatory role for integrins in TGF-beta function in vivo. Here we have developed a novel, biologically relevant experimental model of human airway epithelium using intact human bronchial tissue. We have used this model to determine the function of integrin-mediated activation of TGF-beta in the airway. In human bronchial fragments cultured in vitro, authentic epithelial-stromal interactions were maintained and integrin and TGF-beta expression profiles correlated with profiles found in normal lung. In addition, in this model, we found that either the integrin alphavbeta8 or TGF-beta could inhibit airway epithelial cell proliferation. Furthermore, we found that one mechanism of integrin-alphavbeta8-dependent inhibition of cell proliferation was through activation of TGF-beta because anti-beta8 antibody blocked the majority (76%) of active TGF-beta released from bronchial fragments. These data provide compelling evidence for a functional role for integrin-mediated activation of TGF-beta in control of human airway epithelial proliferation in vivo.
Tight regulation of the inflammatory response is essential for the maintenance of physiologic homeostasis. A potentially important mediator of this process is CD163, a macrophage-specific member of the scavenger receptor cysteine-rich family. CD163 surface expression is up-regulated by glucocorticoids and the anti-inflammatory cytokine interleukin-10, and CD163 is shed acutely from the cell surface in response to lipopolysaccharide. We now demonstrate that transforming growth factor-beta (TGF-beta) markedly reduces expression of CD163. Treatment of primary human monocytes with TGF-beta inhibited basal as well as dexamethasone-induced CD163 mRNA and protein expression. De novo protein synthesis was not required for this inhibition, suggesting that TGF-beta regulates CD163 expression transcriptionally. To delineate this transcriptional regulation, a 2.5-kb fragment of the CD163 promoter was isolated. This promoter was inhibited by TGF-beta, and suppression was dependent on Smad3 expression. These results define a novel function for TGF-beta and implicate an important role for CD163 in the host response to inflammation.
The number of available breast cancer cell (BCC) lines is small, and only a very few of them have been extensively studied. Whether they are representative of the tumours from which they originated remains a matter of debate. Whether their diversity mirrors the well-known inter-tumoural heterogeneity is another essential question. While numerous similarities have long been found between cell lines and tumours, recent technical advances, including the use of micro-arrays and comparative genetic analysis, have brought new data to the discussion. This paper presents most of the BCC lines that have been described in some detail to date. It evaluates the accuracy of the few of them widely used (MCF-7, T-47D, BT-474, SK-BR-3, MDA-MB-231, Hs578T) as tumour models. It is concluded that BCC lines are likely to reflect, to a large extent, the features of cancer cells in vivo. The importance of oestrogen receptor-alpha (gene ESR1 ) and Her-2/ neu ( ERBB2 ) as classifiers for cell lines and tumours is underlined. The recourse to a larger set of cell lines is suggested since the exact origin of some of the widely used lines remains ambiguous. Investigations on additional specific lines are expected to improve our knowledge of BCC and of the dialogue that these maintain with their surrounding normal cells in vivo.
Although interleukin-10 (IL-10) is commonly regarded as an anti-inflammatory, immunosuppressive cytokine that favors tumor escape from immune surveillance, a wealth of evidence is accumulating that IL-10 also possesses some immunostimulating properties. In fact, IL-10 has the pleiotropic ability of influencing positively and negatively the function of innate and adaptive immunity in different experimental models, which makes it questionable to merely categorize this cytokine as a target of anti-immune escape therapeutic strategies or rather, as an immunological adjuvant in the fight against cancer. Here, we review available data about the immunostimulating anticancer properties of IL-10, and in particular, we focus on the hypothesis that in contrast to what occurs in secondary lymphoid organs, IL-10 overexpression within the tumor microenvironment may catalyze cancer immune rejection.
The dual role of transforming growth factor-beta (TGF-β) in modulating macrophage function is an important concept gaining increasing recognition. In addition to its role as a `macrophage-deactivating' agent, TGF-β functions as a monocyte activator, inducing cytoke production and mediating host defence. These functions are context-dependent, modulated by the differentiation state of the cell, the local cytokine environment, and the local levels of TGF-β in itself. In general, during the initial stages of inflammation, TGF-β locally acts as a proinflammatory agent by recruiting and activating resting monocytes. As these cells differentiate specific immunosuppressive actions of TGF-β predominate, leading to resolution of the inflammatory response. Increasing our understanding of the bidirectional regulation of macrophage function will facilitate prediction of the ultimate outcome of modulating TGF-β levels in vivo.
The glucocorticoid-inducible transmembrane protein CD163 is a member of the scavenger receptor cysteine-rich (SRCR) family which is expressed exclusively on human monocytes and macrophages. The expression of the protein is significantly downregulated in response to phorbol 12-myristate 13-acetate (PMA) by a yet unknown mechanism. We now demonstrate that PMA induces shedding of a soluble form of CD163 rather than internalization, revealing a novel regulatory mechanism for a member of the SRCR family. Bisindolylmaleimide I was shown to inhibit phorbol ester-induced shedding, thus implying an involvement of protein kinase C (PKC). Furthermore, cleavage could be prevented by protease inhibitors. Therefore, we suggest that PMA-induced activation of PKC leads to protease-mediated shedding of CD163. These results indicate a specific release mechanism of soluble CD163 by human monocytes which could play an important role in modulating inflammatory processes.
Recent discoveries of endogenous negative regulators of angiogenesis, thrombospondin, angiostatin and glioma-derived angiogenesis inhibitory factor, all associated with neovascularized tumours, suggest a new paradigm of tumorigenesis. It is now helpful to think of the switch to the angiogenic phenotype as a net balance of positive and negative regulators of blood vessel growth. The extent to which the negative regulators are decreased during this switch may dictate whether a primary tumour grows rapidly or slowly and whether metastases grow at all.
The cytokine interleukin-10 (IL-10) has several important activities on cells of the immune system. IL-10 profoundly suppresses activation of macrophages, inhibiting their ability to secrete cytokines and serve as accessory cells for stimulation of T cell and natural killer (NK) cell function. IL-10 also plays a role in stimulating proliferation and differentiation of B cells, mast cells, and both mature and immature T cells. At least two herpesviruses harbor analogs of the IL-10 gene; the Epstein-Barr virus (EBV) homolog (BCRF1, viral IL-10, vIL-10) shares several of the cellular cytokine's activities, one or all of which may be important in the host-virus relationship. This article reviews recent studies on the function of IL-10 and discusses the initial characterization of its receptor.
Chromosome 1 reveals in region 1q21 a most remarkable density of genes that fulfill important functions in terminal differentiation of the human epidermis. These genes encode the cornified envelope precursors loricrin, involucrin, and small proline-rich proteins (SPRR1, SPRR2, and SPRR3), the intermediate filament-associated proteins profilaggrin and trichohyalin, and several S100A calcium-binding proteins. Extending and refining our previous physical map of 1q21 we have now mapped two additional S100A genes as well as the three SPRR subfamilies and resolved the arrangement of involucrin, SPRRs, and loricrin. All genes are linked within 1.9 Mbp of human genomic DNA in the order: S100A10, trichohyalin, profilaggrin, involucrin, SPRR3, SPRR1B, SPRR2A, loricrin, S100A9, S100A9, S100A8, S100A6. Colocalization of genes expressed late during maturation of epidermal cells together with genes encoding calcium-binding proteins is particularly intriguing since calcium levels tightly control the differentiation of epithelial cells and the expression of genes encoding epidermal structural proteins. Accounting for the close functional cooperation among these structurally and evolutionary related genes, we conclude that these loci constitute a gene complex, for which we propose the name epidermal differentiation complex.
Cytokines are hormonE-like proteins and peptides involved in the signalling between cells during immune response. They are produced mainly by lymphocytes (lymphokines) and mononuclear phagocytes (monokines). They are involved in both cell-mediated and humoral immunity. Cytokines fall into a number of categories: interferons (IFNs), interleukins (ILs) and growth factors. It has been indicated in cancer immunology the following cytokines are particularly important: IFNs, TNF-alpha, IL-1, IL-2, IL-4, IL-6, IL-7, IL-9, IL-10, IL-12. Interferons (IFN-gamma in particular) in cooperation with TNF-alpha and IL-1 inhibit proliferation of tumor cells and by their synergic activity with IL-2 induce cytotoxicity of NK-cells. They activate mononuclear phagocytes and by B lymphocyte stimulation augment lysis of cancer cells. TNF-alpha has mainly cytotoxic activity, leading to hemorrhagic necrosis of tumors. It is also an endogenic pyrogen which is together with IL-1 responsible for pyretic status in neoplastic disease. IL-1 stimulates necrotizing activity of TNF-alpha and augments cachexia by anabolism of lipid induction. IL-2, IL-6 and IL-12 induce NK and LAK-cell cytotoxicity. IL-12 inhibits metastasis formation. IL-10, by inhibiting synthesis of cytokines may lead to tumor development.
Human monocytes cultured with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-13 for 7 days differentiate into cells with the morphology and function of dendritic cells (DC). We have investigated the effect of IL-10 on this differentiation pathway. In the presence of IL-10 cells did not develop DC morphology, did not express CD1a and had lower levels of MHC class II. IL-10 promoted the differentiation of large cells with the morphology, cytochemistry and membrane phenotype of macrophages, including staining for nonspecific esterase and high levels of CD14, CD16 and CD68. The effect of IL-10 was dose dependent and was best appreciated when the cytokine was added at the initiation of the culture, as addition on day 3 was less inhibitory. When added to already differentiated DC on day 6, IL-10 caused only a modest reduction of MHC class II and CD1a expression, and no acquisition of the macrophage markers CD14, CD16 and CD68. Prolonged incubation up to 5 days with IL-10 did not induce a shift of differentiated DC to macrophages. On the other hand, the macrophages obtained by culturing for 7 days with GM-CSF+IL-13+IL-10 did not shift to DC upon removal of IL-10 for up to 3 days. Thus, the effect of IL-10 on monocyte differentiation, occurs only at the precursor level and confers an irreversible phenotype. From a functional point of view, cells cultured in the presence of IL-10 were poor stimulators of allogeneic cord blood T cells in mixed lymphocyte reaction (MLR) and presented tetanus toxin (TT) to specific T cell lines with much less efficiency than control DC. In contrast, IL-10-cultured DC showed 7 times greater endocytosis of FITC-dextran. This increased endocytosis was mostly mediated via the mannose receptor, as demonstrated by blocking with unlabeled mannose. In conclusion, IL-10 inhibits DC differentiation from monocytes and, in a substantial proportion of the cells, promotes the differentiation to mature macrophages. Intriguingly, IL-10 inhibits antigen presentation while it stimulates endocytic activity.
Interleukin 10 (IL-10) inhibits the production of a wide range of cytokines in various cell types. The purpose of this study was to determine whether the expression of the IL-10 gene can influence tumor growth and metastatic properties of human melanoma cells. The human melanoma cell line, A375P, which does not produce endogenous IL-10, was transfected with a hygromycin expression vector (control) or a vector containing full-length murine IL-10 cDNA. A375P parental cells, A375P-Hygro, and A375P-IL-10-positive cells were injected s.c. and i.v. into nude mice. A375P-IL-10 cells produced significantly slower growing s.c. tumors and fewer lung metastases than control cells. The tumorigenicity of the human melanoma A375SM and the murine melanoma B16-BL6 cells was also significantly inhibited when they were admixed with A375P-IL-10 but not with A375P-Hygro before s. c. injection into nude mice. The suppression of tumor growth and metastasis was directly correlated with a decrease in neovascularity determined by immunostaining with anti-factor VIII. Because tumor-associated macrophages are the major source of angiogenic molecules in melanoma, we used reverse transcription-PCR to demonstrate that IL-10 down-regulates the production of vascular endothelial growth factor, the most potent angiogenic factor in activated macrophages. Other factors involved in angiogenesis such as IL-1beta, tumor necrosis factor-alpha, IL-6, and the proteinase matrix metalloproteinase-9 were also inhibited in activated macrophages by supernatants from A375P-IL-10 cells. Collectively, these data suggest that the production of IL-10 by tumor cells inhibits macrophages-derived angiogenic factors, and hence, tumor growth and metastasis.
We wish to thank Terry Schoop of Biomed Arts Associates, San Francisco, for preparation of the figures, Cori Bargmann and Zena Werb for insightful comments on the manuscript, and Normita Santore for editorial assistance. In addition, we are indebted to Joe Harford and Richard Klausner, who allowed us to adapt and expand their depiction of the cell signaling network, and we appreciate suggestions on signaling pathways from Randy Watnick, Brian Elenbas, Bill Lundberg, Dave Morgan, and Henry Bourne. R. A. W. is a Ludwig Foundation and American Cancer Society Professor of Biology. His work has been supported by the Department of the Army and the National Institutes of Health. D. H. acknowledges the support and encouragement of the National Cancer Institute. Editorial policy has rendered the citations illustrative but not comprehensive.
CD163 is a recently identified member of the scavenger receptor cysteine-rich superfamily expressed on peripheral blood monocytes and most tissue macrophages. We demonstrate that in vitro culture of human blood monocytes with recombinant M-CSF induces CD163 transcription. In contrast, dendritic differentiation in the presence of GM-CSF and IL-4 suppresses CD163 mRNA and protein levels. Because an important function of CD163 in inflammation has been suggested, we investigated the influence of pro- and anti-inflammatory stimuli on CD163 expression and found a significant suppression by lipoposaccharide and IFN-gamma, whereas IL-10 or dexamethasone strongly induced the expression of CD163. The induction of CD163 mRNA by dexamethasone is suggested to be mediated by several glucocorticoid receptor binding sites located in the proximal promoter region. In addition, this sequence contains potential binding sites for the transcription factors Sp1, C/EBPalpha, Ets-2, PU.1 and AP-1, which have been shown to play an important role in myeloid-specific gene expression. We also identified an L1-transposable element 1.4 kb upstream of the transcription start site that might influence the promoter activity. The function of CD163 may also depend on the use of different isoforms. Several variants of CD163 mRNA have been described that encode proteins with altered cytoplasmic or extracellular domains and thus may differ in their functional properties. We analyzed the genomic organization of the CD163 gene and could demonstrate that these isoforms result from alternative splicing. Further characterization of the isoforms may help to understand the complete function of CD163.
The transforming growth factor beta (TGF-beta) family of hormonally active polypeptides have attracted much attention because of their ability to control cellular functions that underwrite animal embryo development and tissue homeostasis. TGF-beta family members act by modifying the expression of specific sets of target genes, and biologists pursuing the elucidation of TGF-beta signaling mechanisms have turned up a fairly simple system, linking membrane TGF-beta receptors to such genes (for recent reviews, see Heldin et al. 1997; Massague 1998; Whitman 1998; Massague and Wotton 2000). If a TGF-beta signaling system can be so simple, and yet so powerful, then an elaborate network of regulators must keep control over the inputs, activity, and outcomes of this system. A multitude of regulatory mechanisms have been recently uncovered that control the access of TGF-beta family members to their receptors, the activity of their receptors and receptor substrates, and the nuclear function of the transcriptional complexes generated by this pathway. The regulatory mechanisms operating in the prereceptor phase of a TGF-beta signaling pathway can be as intricate and physiologically important as those operating downstream of TGF-beta receptors. These control mechanisms, which are central to understanding the physiology of TGF-beta signaling, are reviewed here.
CD163 is a recently identified member of the scavenger receptor cysteine-rich superfamily, which is expressed on peripheral blood monocytes and most tissue macrophages and is thought to play an important role in the regulation of the inflammatory response of these cells. Cross-linking of CD163 on glucocorticoid-stimulated macrophages results in the secretion of several proinflammatory cytokines, but the precise mechanism of CD163 mediated signal transduction is not understood. The existence of several CD163 isoforms, which differ in the structure of their cytoplasmic domains and putative phosphorylation sites, suggests that these isoforms also differ in their signaling mechanism. Using the Yeast Two-Hybrid system and further in vitro and in vivo studies, we identified the regulatory beta-subunit of casein kinase II (CKII), which specifically binds to the cytoplasmic domain of CD163 and its isoforms. We also found, that in vitro the CD163 isoforms differ in their association with the CKII holoenzyme and in the phosphorylation by CKII. Furthermore, we demonstrated that the cytoplasmic domains of CD163 variants are phosphorylated by PKC-alpha in vitro. Inhibition studies using specific kinase inhibitors reveal that both CKII and PKC are involved in the CD163 signaling mechanism resulting in the secretion of proinflammatory cytokines.
Cells of the mononuclear phagocyte lineage include macrophages, microglia, osteoclasts, and myeloid dendritic cells. These cell types are all derived from blood monocytes, which are the product of hematopoietic stem cell differentiation. In this review we use specific examples of macrophage-expressed genes to illustrate potential regulatory strategies for directing macrophage-specific gene expression. The examples we have chosen-the human c-fes gene, the murine spi-1 (PU.1) gene, the human RANTES promoter, and the human CD68 gene-illustrate different aspects of constitutive and inducible gene expression in macrophages. One important challenge for future work in this field will be to identify the molecular events that dictate lineage decisions during the differentiation of mononuclear phagocytes from hematopoietic progenitor cells. Another important goal will be to understand how groups of macrophage genes are coordinately expressed in response to physiological, immunological, and inflammatory stimuli. A better understanding of macrophage gene expression may find application in gene therapy, genetic vaccination, and the development of new antiinflammatory drugs.
Colony stimulating factor 1 (CSF-1), a major regulator of the mononuclear phagocytic lineage, is expressed in more than 70% of human breast cancers and its expression is correlated with poor prognosis. Studies of CSF-1 null mutant mice demonstrated that CSF-1 plays an important role in normal mammary ductal development as well as in mammary tumor progression to metastasis. CSF-1 regulates these processes through the recruitment and regulation of macrophages, cells that become associated with mammary tumors and the terminal end buds at the end of the growing ducts. This phenomenon suggests that the tumors subvert normal developmental processes to allow invasion into the surrounding stroma, a process that gives the tumor access to the vasculature and consequently the promotion of metastasis. In addition, soluble CSF-1 secreted from the tumor acts to divert antitumor macrophage responses and suppresses the differentiation of mature tumor-antigen-presenting dendritic cell This review discusses these observations in detail and attempts to fit them into a larger picture of CSF-1 and macrophage action in the regulation of normal mammary gland development and tumor progression.
We have recently demonstrated that malignant cells can hybridize with tissue macrophages in vitro, giving rise to tumorigenic hybrids. We now demonstrate that this can occur spontaneously in vivo as a result of fusion between inoculated Meth A sarcoma cells and host cells, presumably macrophages. Thus, from tumor cell suspensions prepared by collagenase perfusion and density centrifugation, hybrid cells could be isolated that were neoplastic but in contrast to Meth A expressed macrophage markers and had phagocytic capacity. Their morphologic features were intermediate between Meth A and macrophages. By taking advantage of a semiallogeneic experimental system by inoculation of Meth A cells from BALB/c (H-2 K(d)) into (BALB.K x BALB/c) F(1) (H-2(k/d)), hybrid cells from these tumors could be shown to express MHC antigens of both the Meth A and the host haplotypes. Hybrid cells grew faster than Meth A cells in vivo, indicating acquisition of growth-promoting properties through heterotypic cell fusion.
Statistical measures are described that are used in diagnostic imaging for expressing observer agreement in regard to categorical data. The measures are used to characterize the reliability of imaging methods and the reproducibility of disease classifications and, occasionally with great care, as the surrogate for accuracy. The review concentrates on the chance-corrected indices, kappa and weighted kappa. Examples from the imaging literature illustrate the method of calculation and the effects of both disease prevalence and the number of rating categories. Other measures of agreement that are used less frequently, including multiple-rater kappa, are referenced and described briefly.
Problem:
Reduced placental (trophoblast) cytokine interleukin-10 (IL-10) occurs in human pre-eclampsia. Along with an increase in inflammatory cytokines this may play an important role in the development of hypertension in pregnancy. It is not clear whether the changes in placental IL-10 are due to a change in the placental cell production of IL-10 or a result of changes in cytokine receptor status in adjacent tissues. This study is aimed at qualifying the presence and distribution of IL-10 receptors in women with a pre-eclamptic outcome compared to normal pregnancy and gestational hypertension.
Method of study:
Patients at the KGV Hospital, Sydney was selected for the study. Placentas were collected fresh and paraffin serial sections made. Sections were stained with IL-10 receptor antibody (10 microgram/mL) using avidin-biotin immunohistochemistry. Tissues of patients with pre-eclampsia (n=11) were compared with normal pregnancy (n=12). Pre-eclampsia was defined as a blood pressure >140/90 mmHg on two occasions and de nova proteinuria >300 mg per day which resolved post-partum. The fetal weights, gestational ages and maternal ages at delivery were compared (ANOVA) and the differences in staining of decidual and villous tissues were graded according to density. Statistical comparisons were made using the Kruskal-Wallis test.
Results:
The groups were similar for maternal gestational age but delivered at earlier gestation and with lower fetal weight. There was significantly less villous cytotrophoblast staining for IL-10 receptor in all groups (P=0.012) compared to decidual trophoblast cells. There was equal intensity and density of extravillous straining observed in normal pregnancy (45 +/- 12%) positive cells compared to pre-eclampsia (27 +/- 12%).
Conclusion:
IL-10 receptors are present in greater concentration in the extravillous (decidual) trophoblast compared to villi. The decrease in IL-10 produced by trophoblast cells in pre-eclampsia is not explained by a difference in the IL-10 receptor distribution compared to normal pregnancy.
Cell fusion has long been known to produce viable cells and to have a major role in mammalian development and differentiation. As gene expression profiles can change after cell fusion, this event must be also considered as an alternative explanation for the many cases of 'stem cell plasticity' that have been recently described and are promoted as a promising therapeutic strategy. Cell fusion has been demonstrated to occur in some recent studies, and the available evidence is often not inconsistent with cell fusion in others. Cell fusion itself has therapeutic potential, but low rates of spontaneous fusion and safety concerns may ultimately limit its use.
Although haptoglobin polymorphism has been shown to be a genetic risk factor in coronary artery disease, its mechanisms of action are incompletely defined. Recently, a macrophage scavenger receptor for the uptake of haptoglobin-hemoglobin (Hp-Hb) complexes was cloned and designated CD163. Macrophage expression of CD163 is increased by glucocorticoids, IL-10 and IL-6. To better understand the in vivo response of CD163 to an inflammatory stimulus and glucocorticoid treatment, we studied 18 patients who underwent elective coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB). We report a rapid increase in plasma levels of soluble CD163 by 1 h post-declamping the aorta during CABG surgery with CPB. Furthermore, we demonstrate significant increases in monocyte CD163 on post-operative day 1; 14-fold for patients pre-treated with methylprednisolone and 3-fold for those who did not receive exogenous glucocorticoids. These findings show CD163 to be rapidly mobilized in response to systemic inflammatory stimuli and to be affected significantly by glucocorticoids in vivo. The proposed role of CD163 as a Hp-Hb scavenger and anti-inflammatory molecule, in conjunction with the results of this study, make CD163 an intriguing target for potential manipulation of the acute response to inflammation.
Recent evidence suggests that human cells require more genetic changes for neoplastic transformation than do their murine counterparts. However, a precise enumeration of these differences has never been undertaken. We have determined that perturbation of two signaling pathways-involving p53 and Raf-suffices for the tumorigenic conversion of normal murine fibroblasts, while perturbation of six pathways-involving p53, pRb, PP2A, telomerase, Raf, and Ral-GEFs-is needed for human fibroblasts. Cell type-specific differences also exist in the requirements for tumorigenic transformation: immortalized human fibroblasts require the activation of Raf and Ral-GEFs, human embryonic kidney cells require the activation of PI3K and Ral-GEFs, and human mammary epithelial cells require the activation of Raf, PI3K, and Ral-GEFs.
Paraffin-section immunohistochemical analysis was performed using a monoclonal antibody against CD163 to evaluate the antibody's usefulness in identifying cells of monocyte/macrophage lineage in normal and neoplastic conditions. Normal human tissue samples and samples from 211 hematopoietic disorders and 115 nonhematopoietic neoplasms were examined. The distribution of KP1 and PG-M1, monoclonal antibodies to the macrophage-associated CD68 antigen, also were evaluated for comparison. CD163 immunoreactivity was observed in resident macrophages of all normal tissue samples except splenic white pulp macrophages and germinal center tingible body macrophages. Among hematopoietic disorders and nonhematopoietic neoplasms, CD163 expression was restricted largely to cases of chronic myelomonocytic leukemia, histiocytic sarcoma, sinus histiocytosis with massive lymphadenopathy, and littoral cell angioma. Acute myeloid leukemias (AMLs) with monocytic differentiation were CD163- with the exception of 1 case of acute monoblastic leukemia. Most myeloid sarcomas also were CD163-. Compared with the CD68 antibodies, CD163 demonstrated greater specificity as a marker of disorders of monocyte/macrophage origin. However, immunohistochemical evaluation of CD163 expression does not seem to be a sensitive means of determining monocytic differentiation in AMLs in paraffin sections or establishing a diagnosis of myeloid sarcoma.
CD163, a hemoglobin scavenger receptor, is expressed in monocytes and macrophages. We tested the expression of the CD163 protein in 1,105 human malignancies and normal tissues using tissue microarrays and conventional paraffin-embedded tissue sections. Besides staining nonneoplastic monocytes and histiocytes (tissue macrophages), membranous/cytoplasmic staining for CD163 was primarily limited to neoplasms with monocytic/histiocytic differentiation. CD163 reactivity was not observed in normal tissues, lymphomas, carcinomas, and in a majority of mesenchymal neoplasms, including follicular dendritic cell tumors (0 of 4), although it stained admixed histiocytes. Staining for CD163 was seen in Rosai-Dorfman disease (5 of 6), histiocytic sarcoma (3 of 4), littoral cell angioma (6 of 6), and Langerhans cell histiocytosis (3 of 5). A subset of atypical fibrous histiocytomas (9 of 16), benign fibrous histiocytomas (6 of 9), and atypical fibroxanthomas (1 of 3) also showed CD163 staining. Our studies also confirm earlier work showing that CD163 is expressed in acute myeloid leukemia with monocytic differentiation (AML, FAB subtype M5) (2 of 6), as well as a majority of giant cell tenosynovial tumors (7 of 8). Its limited range of expression and tissue specificity indicate that CD163 may have significant diagnostic utility in separating specific tumors with monocytic and histiocytic derivation from other entities in their differential diagnosis.
Intestinal macrophage responses to luminal bacteria and their constituents are important in mucosal inflammatory responses. We investigated the responses of intestinal macrophages to free lipopolysaccharide (LPS) and Escherichia coli. Macrophages were isolated from normal terminal ileum and colon by allowing them to migrate out of the lamina propria of mucosal samples denuded of epithelial cells. Following exposure to free LPS or fluorescein-labelled E. coli, responsiveness was studied by intracellular expression of tumour necrosis factor-alpha (TNF-alpha). CD14, CD33, CD68, TLR2 and TLR4 expression was studied by fluorescence-activated cell sorter (FACS). TLR and NOD2 expression was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). CD14 was expressed by 36.5 +/- 4.0% of the macrophages obtained following migration out of the lamina propria. These cells also expressed TLR2, TLR4 and NOD2. Of cells exposed to free LPS or those that had taken up E. coli, a greater proportion of CD14(+) than CD14(-) macrophages expressed intracellular TNF-alpha. Moreover, a greater proportion of macrophages (CD14(+) and CD14(-)) demonstrated responses to E. coli than free LPS. In conclusion, a proportion of macrophages obtained following migration out of the lamina propria of normal terminal ileal and colonic mucosal samples express CD14, TLR2 and TLR4. These cells respond to free LPS and E. coli, as demonstrated by the expression of TNF-alpha.
Mature tissue macrophages form a first line of defense to recognize and eliminate potential pathogens; these specialized cells are capable of phagocytosis, degradation of self and foreign materials, establishment of cell-cell interactions, and the production of inflammatory mediators. Mature tissue macrophages express a variety of receptors, including the scavenger receptor cystein-rich (SRCR) superfamily members. CD163 is a member of the SRCR family class B and is expressed on most subpopulations of mature tissue macrophages. The best characterized function of CD163, which is essentially a homeostatic one, is related to the binding of Hemoglobin:Haptoglobin complexes. Furthermore, it has been suggested that CD163 positive macrophages or the soluble form of CD163 plays a role in the resolution of inflammation, as they are found in high numbers in inflamed tissue.
Malignant cells express molecular pathways that are also expressed by myeloid cells. Such behaviour is associated with loss of homotypic adhesion between cells, changes in the cellular matrix, induction of angiogenesis, motility, chemotaxis, and several immune-signalling pathways. The overlap between malignant cells and myeloid cells could be explained by one mechanism: fusion of myeloid cells and tumour cells, as noted in animal studies and in two patients with renal-cell carcinoma who underwent bone-marrow transplantation. An overlapping trait in these cells is their glycosylation patterns: hybrids have high expression of N-terminal glycosylation and beta1,6-branched oligosaccharides. In macrophages and cancer cells, these structures have a role in motility and systemic migration; in cancer, they are associated with metastasis and poor prognosis. In addition to myeloid traits, fusion might contribute to aneuploidy and plasticity in cancer. Understanding metastatic cells as myeloid-tumour hybrids suggests new strategies for diagnosis, treatment, and prevention of malignant disease.