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Identification of plasma Complement C3 as a potential biomarker for neuroblastoma using a quantitative proteomic approach
Abstract and Figures
Unlabelled:
The majority of patients diagnosed with neuroblastoma present with aggressive disease. Improved detection of neuroblastoma cancer cells following initial therapy may help in stratifying patient outcome and monitoring for relapse. To identify potential plasma biomarkers, we utilised a liquid chromatography-tandem mass spectrometry-based proteomics approach to detect differentially-expressed proteins in serum from TH-MYCN mice. TH-MYCN mice carry multiple copies of the human MYCN oncogene in the germline and homozygous mice for the transgene develop neuroblastoma in a manner resembling the human disease. The abundance of plasma proteins was measured over the course of disease initiation and progression. A list of 86 candidate plasma biomarkers was generated. Pathway analysis identified significant association of these proteins with genes involved in the complement system. One candidate, complement C3 protein, was significantly enriched in the plasma of TH-MYCN(+/+) mice at both 4 and 6weeks of age, and was found to be elevated in a cohort of human neuroblastoma plasma samples, compared to healthy subjects. In conclusion, we have demonstrated the suitability of the TH-MYCN(+/+) mouse model of neuroblastoma for identification of novel disease biomarkers in humans, and have identified Complement C3 as a candidate plasma biomarker for measuring disease state in neuroblastoma patients.
Biological significance:
This study has utilised a unique murine model which develops neuroblastoma tumours that are biologically indistinguishable from human neuroblastoma. This animal model has effectively allowed the identification of plasma proteins which may serve as potential biomarkers of neuroblastoma. Furthermore, the label-free ion count quantitation technique which was used displays significant benefits as it is less labour intensive, feasible and accurate. We have been able to successfully validate this approach by confirming the differential abundance of two different plasma proteins. In addition, we have been able to confirm that the candidate biomarker Complement C3, is more abundant in the plasma of human neuroblastoma patient plasma samples when compared to healthy counterparts. Overall we have demonstrated that this approach can be potentially useful in the identification of biomarker candidates, and that further validation of the candidates may lead to the discovery of novel, clinically useful diagnostic tools in the detection of sub-clinical neuroblastoma.
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... NB is a most common solid tumor in children. The current treatment approaches compromise surgical resection, radiotherapy and immunotherapy (9). With grim outcome in nearly 12% of children younger than 15 years of age, high-risk NB remains as a significant disease burden in pediatric neuro-oncology. ...
... Several studies showed that NB is a heterogeneous and complex disease and a lot of factors such as stage of disease, age and genetic alterations involved in progression of this malignancy (1)(2)(3)(4)(5)(6)(7). Beside genetic heterogeneity and aberrant epigenetic regulation, abnormal expression of small non-coding RNAs (miRNAs) has revealed indispensable role in NB establishment and resistance to current standard treatments (8)(9)(10). Different expression of miRNAs between MYC amplified and non-amplified human neuroblastoma tumors corroborated the role of miRNAs in neurblastoma pathogenesis (10)(11)(12)(13). ...
... In one study, identification of plasma Complement C3 as a potential biomarker for NB using a quantitative proteomic approach. They have demonstrated the suitability of the TH-MYCN +/+ mouse model of NB for identification of novel disease biomarkers in humans, and have identified Complement C3 as a candidate plasma biomarker for measuring disease state in NB patients (9). In other study, Sandoval et al, the utilizing of proteomics approaches for investigating other proteins profiles as new candidate serum biomarkers in an established animal model of advance stage human NB. ...
Neuroblastoma (NB) with various clinical presentation is a known childhood malignancy.
Despite significant progress in treatment of NB afflicted patients, high risk disease is usually
associated with poor outcome, resulting in long-term survival of less that 50%. Known as a
disease most commonly originated form the nerve roots, the variants involved in NB
imitation and progression remain to be elucidated. The outcome of low to intermediate risk
disease is favorable whereas the high risk NB disease with dismal prognosis, positing the
necessity of novel approaches for early detection and prognostication of advanced
disease. Tailored immunotherapy approaches have shown significant improvement in highrisk
NB patients. It has found a link between Gangliosides and progression of NB. The vast
majority of neuroblastoma tumors express elevated levels of GD2, opening new insight into
using anti-GD2 drugs as potential treatments for NBs. Implication of anti-GD2 monoclonal
antibodies for treatment of high risk NBs triggers further investigation to unearth novel
biomarkers as prognostic and response biomarker to guide additional multimodal tailored
treatment approaches. A growing body of evidence supports the usefulness of miRNAs to
evaluate high risk NBs response to anti-GD2 drugs and further prevent drug-related toxicities
in refractory or recurrent NBs. miRNAs and circulating proteins in body fluids (plasma,
and serum) present as potential biomarkers in early detection of NBs. Here, we summarize
various biomarkers involved in diagnosis, prognosis and response to treatment in patients
with NB. We further attempted to overview prognostic biomarkers in response to treatment
with anti-GD2 drugs.
... Nevertheless, the TH-MYCN murine model-as well as derived modified models (e.g., TH-MYCN/Mdm2 +/− , TH-MYCN/TH-Cre/Casp8 flox/flox , LSL-MYCN; Dbh-iCre, TH-MYCN/Trp53 KI/KI ), which can overcome some issues associated with the original TH-MYCN mice-are extensively utilized in various fields of neuroblastoma research. These include testing the potential chemotherapeutics [187,[190][191][192][193][194][195][196], the identification of biomarkers [197,198], and a study on various aspects and mechanisms of tumorigenesis, and metastasis, as well as the development and progression of neuroblastomas [43,195,[199][200][201][202][203][204][205]. ...
Simple Summary
Neuroblastoma is a pediatric tumor originating from the precursors of sympathetic nerves. The disease is known for its high heterogeneity. Hence, developing adequate preclinical models reflecting the complex biology of neuroblastoma is particularly challenging. This paper describes the current status of the available neuroblastoma models with their strengths and limitations, and demonstrates the future perspectives for preclinical neuroblastoma research.
Abstract
Preclinical in vitro and in vivo models remain indispensable tools in cancer research. These classic models, including two- and three-dimensional cell culture techniques and animal models, are crucial for basic and translational studies. However, each model has its own limitations and typically does not fully recapitulate the course of the human disease. Therefore, there is an urgent need for the development of novel, advanced systems that can allow for efficient evaluation of the mechanisms underlying cancer development and progression, more accurately reflect the disease pathophysiology and complexity, and effectively inform therapeutic decisions for patients. Preclinical models are especially important for rare cancers, such as neuroblastoma, where the availability of patient-derived specimens that could be used for potential therapy evaluation and screening is limited. Neuroblastoma modeling is further complicated by the disease heterogeneity. In this review, we present the current status of preclinical models for neuroblastoma research, discuss their development and characteristics emphasizing strengths and limitations, and describe the necessity of the development of novel, more advanced and clinically relevant approaches.
... The expression of complement C3 (C3) in the sEV fractions of bladder cancer patients was increased in this biomarker discovery study. The upregulation of C3 was also demonstrated in several types of cancer and in different liquid biopsies [50][51][52][53][54]. Increased expression of C3 could indicate the activation of the complement cascade pathway: the immunity system is activated and can destroy tumor cells. ...
Urinary extracellular vesicles (EVs) are an attractive source of bladder cancer biomarkers. Here, a protein biomarker discovery study was performed on the protein content of small urinary EVs (sEVs) to identify possible biomarkers for the primary diagnosis and recurrence of non-muscle-invasive bladder cancer (NMIBC). The sEVs were isolated by ultrafiltration (UF) in combination with size-exclusion chromatography (SEC). The first part of the study compared healthy individuals with NMIBC patients with a primary diagnosis. The second part compared tumor-free patients with patients with a recurrent NMIBC diagnosis. The separated sEVs were in the size range of 40 to 200 nm. Based on manually curated high quality mass spectrometry (MS) data, the statistical analysis revealed 69 proteins that were differentially expressed in these sEV fractions of patients with a first bladder cancer tumor vs. an age- and gender-matched healthy control group. When the discriminating power between healthy individuals and first diagnosis patients is taken into account, the biomarkers with the most potential are MASP2, C3, A2M, CHMP2A and NHE-RF1. Additionally, two proteins (HBB and HBA1) were differentially expressed between bladder cancer patients with a recurrent diagnosis vs. tumor-free samples of bladder cancer patients, but their biological relevance is very limited.
... In another study, Tropomyosin receptor kinase A (TrkA)-dependent target proteins were determined in SK-N-MC neuroblastoma cells by using a proteomic approach (19). In a study by Kim et al., component C3 was proposed as a candidate plasma biomarker in TH-MYCN+/+ mouse model by using liquid tandem mass spectrometry (20). Receptor tyrosine kinases RET, insulin growth factor 1 like-1 receptor/1K and fibroblast growth factor receptor-1 were shown to play an important role in NB upon comparison of protein profiles of different neuroblastoma cell lines by using shotgun Liquid Chromatography/Mass Spectrometry (LC/MS) (21). ...
Purpose: Determination of proteomic differences plays an important role in biomarker investigations. Due to its heterogenic molecular background, identification of certain biomarkers is still a demand both for diagnosis and for prognosis of neuroblastoma. In this study, it is aimed to identify some marker proteins/mechanisms that may play role in neuroblastoma prognosis. Methods: A proteomic approach was performed for different risk groups of the disease by using matrix-assisted laser desorption ionization–time of flight (MALDI-TOF/TOF) approach. Mononuclear cell pools from blood samples of patients for risk groups were constructed and protein expression changes for different groups were identified. Real-time PCR analysis were performed for N-MYC, 11q, 1p and 17q status of these patients and risk groups were determined from tumor samples. Results: Manganese-superoxide dismutase (SOD2) protein was significantly increased in high-risk group of neuroblastoma patients. Conclusion: SOD2 may play an important role in neuroblastoma progression and be a candidate prognostic peripheral blood marker for neuroblastoma patients.
... Activation of C3 is central to the complement pathways, which collectively results in the elimination of the antigen target [41]. A high level of C3 has been observed in many cancer patients` serum [42,43]. Recent studies have suggested that C3 aids tumor growth through an immunosuppressive mechanism [44,45]. ...
Background
Despite papillary renal cell carcinoma (pRCC) being the second most common type of kidney cancer, the underlying molecular mechanism remains unclear. Targeted therapies in the past have not been successful because of the lack of a clear understanding of the molecular mechanism. Hence, exploring the underlying mechanisms and seeking novel biomarkers for pursuing a precise prognostic biomarker and appropriate therapies are critical.
Material and methods
In our research, the differentially expressed genes (DEGs) were screened from the TCGA and GEO databases, and a total of 149 upregulated and 285 downregulated genes were sorted. This was followed by construction of functional enrichment and protein–protein interaction (PPI) network, and then the top 15 DEGs were selected for further analysis. The P4HB gene was chosen as our target gene by repetitively validating multiple datasets, and higher levels of P4HB expression predicted lower overall survival (OS) in patients with pRCC.
Results
We found that P4HB not only connects with immune cell infiltration and co-expression with PD-1, PD-L2, and CTLA-4 , but also has a strong connection with the newly discovered hot gene, TOX .
Conclusion
We speculate that P4HB is a novel gene involved in the progression of pRCC through immunomodulation.
... Complement activation has been described in cancer patients with hematological malignancies such as lymphomas (20), and in a plethora of solid tumors (21)(22)(23). Furthermore, intact complement proteins were found increased in blood of patients with lung cancer (24,25), neuroblastoma (26), and digestive tract tumors (27). However, complementmediated cytotoxicity is circumvented by different mechanisms, most of which include the upregulation of complement regulatory proteins (28)(29)(30). ...
The complement system represents a pillar of the innate immune response. This system, critical for host defense against pathogens, encompasses more than 50 soluble, and membrane-bound proteins. Emerging evidence underscores its clinical relevance in tumor progression and its role in metastasis, one of the hallmarks of cancer. The multistep process of metastasis entails the acquisition of advantageous functions required for the formation of secondary tumors. Thus, targeting components of the complement system could impact not only on tumor initiation but also on several crucial steps along tumor dissemination. This novel vulnerability could be concomitantly exploited with current strategies overcoming tumor-mediated immunosuppression to provide a substantial clinical benefit in the treatment of metastatic disease. In this review, we offer a tour d'horizon on recent advances in this area and their prospective potential for cancer treatment.
... Fbs1 GYR enrichment also identified 478 unique N-glycosites, compared to 343 following lectin enrichment, and 224 unique N-glycosites in the pre-enrichment sample (Fig. 7b). Our data demonstrate that (Fig. 7c). Figure 7d shows the N-glycosylation microheterogeneity analysis for a single potential disease biomarker, human Complement C3 43 . In this case, Fbs1 GYR enrichment clearly allows identification of more glycan types and spectra at each glycosite relative to the pre-enrichment and lectin enrichment samples. ...
A method for selective and comprehensive enrichment of N-linked glycopeptides was developed to facilitate detection of micro-heterogeneity of N-glycosylation. The method takes advantage of the inherent properties of Fbs1, which functions within the ubiquitin-mediated degradation system to recognize the common core pentasaccharide motif (Man3GlcNAc2) of N-linked glycoproteins. We show that Fbs1 is able to bind diverse types of N-linked glycomolecules; however, wild-type Fbs1 preferentially binds high-mannose-containing glycans. We identified Fbs1 variants through mutagenesis and plasmid display selection, which possess higher affinity and improved recovery of complex N-glycomolecules. In particular, we demonstrate that the Fbs1 GYR variant may be employed for substantially unbiased enrichment of N-linked glycopeptides from human serum. Most importantly, this highly efficient N-glycopeptide enrichment method enables the simultaneous determination of N-glycan composition and N-glycosites with a deeper coverage (compared to lectin enrichment) and improves large-scale N-glycoproteomics studies due to greatly reduced sample complexity.
Constituent of innate immunity, complement is present in the tumor microenvironment. The functions of complement include clearance of pathogens and maintenance of homeostasis, and as such could contribute to an anti-tumoral role in the context of certain cancers. However, multiple lines of evidence show that in many cancers, complement has pro-tumoral actions. The large number of complement molecules (over 30), the diversity of their functions (related or not to the complement cascade), and the variety of cancer types make the complement-cancer topic a very complex matter that has just started to be unraveled. With this review we highlight the context-dependent role of complement in cancer. Recent studies revealed that depending of the cancer type, complement can be pro or anti-tumoral and, even for the same type of cancer, different models presented opposite effects. We aim to clarify the current knowledge of the role of complement in human cancers and the insights from mouse models. Using our classification of human cancers based on the prognostic impact of the overexpression of complement genes, we emphasize the strong potential for therapeutic targeting the complement system in selected subgroups of cancer patients.
Advancing in genome sequencing has greatly propelled the understanding of the living world, however, it is insufficient for full description of a biological system. Focusing on, proteomics has emerged as another large-scale platform for improving the understanding of biology. Proteomic experiments can be used for different aspects of clinical and health sciences such as food technology, biomarker discovery and drug target identification. Since proteins are main constituents of foods, proteomic technology can monitor and characterize protein content of foods and their change during production process. The proteomic biomarker discovery is advanced in various diseases such as cancer, cardiovascular diseases, AIDS and renal diseases which provide non-invasive methods by the use of body fluids such as urine and serum. Proteomics is also used in drug target identification using different approaches such as chemical proteomics and protein interaction networks. The development and application of proteomics has increased tremendously over the last decade. Advances in proteomics methods offer many promising new directions of studying in clinical fields. In this regard, we want to discuss proteomics technology application in food investigations, drug and biomarker discovery will be discussed.
The mouse is the most commonly used laboratory animal, with more than 14 million mice being used for research each year in North America alone. The number and diversity of mouse models is increasing rapidly through genetic engineering strategies, but detailed characterization of these models is still challenging because most phenotypic information is derived from time-consuming histological and biochemical analyses. To expand the biochemists' toolkit, we generated a set of targeted proteomic assays for mouse plasma and heart tissue, utilizing bottom-up LC/MRM-MS with isotope-labeled peptides as internal standards. Protein quantitation was performed using reverse standard curves, with LC-MS platform and curve performance evaluated by quality control (QC) standards. The assays comprising the final panel (101 peptides for 81 proteins in plasma; 227 peptides for 159 proteins in heart tissue) have been rigorously developed under a fit-for-purpose approach and utilize stable-isotope labeled peptides for every analyte to provide high-quality precise relative quantitation. In addition, the peptides have been tested to be interference-free and the assay is highly multiplexed, with reproducibly determined protein concentrations spanning >4 orders of magnitude. The developed assays have been used in a small pilot study to demonstrate their application to molecular phenotyping or biomarker discovery/verification studies. This article is protected by copyright. All rights reserved.
Chronic kidney disease (CKD) is frequently associated with protein-energy wasting, a recognized strong predictive factor of mortality. Zinc α2-glycoprotein (ZAG) is a new adipokine involved in body weight control through its lipid-mobilizing activity. Here we tested whether the uremic environment in CKD could alter ZAG production by white adipose tissue and contribute to CKD-associated metabolic disturbances. Compared with normal plasma, uremic plasma induced a significant increase in ZAG synthesis (124%), was associated with a significant increase in basal lipolysis (31%), and significantly blunted lipogenesis (-53%) in 3T3-L1 adipocytes in vitro. In 5/6 nephrectomized rats and mice in vivo, there was a significant decrease in white adipose tissue accretion (-44% and -43%, respectively) and a significantly higher white adipose tissue content of ZAG protein than in sham-operated, pair-fed control animals (498% and 106%, respectively). Subcutaneous white adipose tissue biopsies from patients with end-stage renal disease exhibited a higher content of ZAG (573%) than age-matched controls. Thus, the ZAG content is increased in white adipose tissue from patients or animal models with CKD. Overproduction of ZAG in CKD could be a major contributor to metabolic disturbances associated with CKD.Kidney International advance online publication, 20 February 2013; doi:10.1038/ki.2013.9.
Response rates to chemotherapy remain highly variable in breast cancer patients. We set out to identify genes associated with chemotherapy resistance. We analyzed what is currently the largest single-institute set of gene expression profiles derived from breast cancers prior to a single neoadjuvant chemotherapy regimen (dose-dense doxorubicin and cyclophosphamide). We collected, gene expression-profiled, and analyzed 178 HER2-negative breast tumor biopsies ("NKI dataset"). We employed a recently developed approach for detecting imbalanced differential signal (DIDS) to identify markers of resistance to treatment. In contrast to traditional methods, DIDS is able to identify markers that show aberrant expression in only a small subgroup of the non-responder samples. We found a number of markers of resistance to anthracycline-based chemotherapy. We validated our findings in three external datasets, totaling 456 HER2-negative samples. Since these external sets included patients who received differing treatment regimens, the validated markers represent markers of general chemotherapy resistance. There was a highly significant overlap in the markers identified in the NKI dataset and the other three datasets. Five resistance markers, SERPINA6, BEX1, AGTR1, SLC26A3, and LAPTM4B, were identified in three of the four datasets (p value overlap < 1 × 10(-6)). These five genes identified resistant tumors that could not have been identified by merely taking ER status or proliferation into account. The identification of these genes might lead to a better understanding of the mechanisms involved in (clinically) observed chemotherapy resistance and could possibly assist in the recognition of breast cancers in which chemotherapy does not contribute to response or survival.
The mammalian complement system is a phylogenetically ancient cascade system that has a major role in innate and adaptive immunity. Activation of component C3 (1,641 residues) is central to the three complement pathways and results in inflammation and elimination of self and non-self targets. Here we present crystal structures of native C3 and its final major proteolytic fragment C3c. The structures reveal thirteen domains, nine of which were unpredicted, and suggest that the proteins of the 2-macroglobulin family evolved from a core of eight homologous domains. A double mechanism prevents hydrolysis of the thioester group, essential for covalent attachment of activated C3 to target surfaces. Marked conformational changes in the -chain, including movement of a critical interaction site through a ring formed by the domains of the -chain, indicate an unprecedented, conformation-dependent mechanism of activation, regulation and biological function of C3.
Legumain is a member of the asparaginyl endopeptidase family that is over-expressed in response to hypoxic stress on mammary adenocarcinoma, colorectal cancer, proliferating endothelial cells, and tumor-associated macrophages (TAMs). Here, we demonstrate that elevated expression of legumain in ovarian cancer by a proteomic approach using isobaric tags for relative and absolute quantification (iTRAQ) followed by liquid chromatography-mass spectrometry (LC-MS/MS). To investigate the relationship between legumain expression and ovarian cancer development, we tested legumain expression in malignant human ovarian tumors (n = 60), borderline ovarian tumors (n = 20), benign ovarian tumors (n = 20), and normal ovary samples (n = 20) using immunohistochemical assay (IHC). A correlation between legumain expression, and clinocopathologic and biological variables was also established. Importantly, increased legumain expression was validated by real-time PCR and Western blots, correlated positively with an increased malignancy of ovarian tumors (P < 0.01). In fact, patients with strong legumain expression had a worse prognosis (P = 0.03). In addition, results of in vitro experiments revealed that over-expression of legumain correlates with increased cell migration and invasion of ovarian cancer cells. Although legumain's functional role and clinical utility remain to be established, our results indicated that a sensitive assay for early expression of legumain may serve as both a potential biomarker and a molecular target for treatment of ovarian cancer.
Lung cancer is the leading cause of cancer-related death in the world. To explore tumor biomarkers for clinical application, two-dimensional fluorescence difference gel electrophoresis and subsequent MALDI-TOF/TOF mass spectrometry were performed to identify proteins differentially expressed in 12 pairs of lung squamous cell tumors and their corresponding normal tissues. A total of 28 nonredundant proteins were identified with significant alteration in lung tumors. The up-regulation of isocitrate dehydrogenase 1 (IDH1), superoxide dismutase 2, 14-3-3ε, and receptor of activated protein kinase C1 and the down-regulation of peroxiredoxin 2 in tumors were validated by RT-PCR and Western blot analysis in independent 15 pairs of samples. Increased IDH1 expression was further verified by the immunohistochemical study in extended 73 squamous cell carcinoma and 64 adenocarcinoma clinical samples. A correlation between IDH1 expression and poor overall survival of non-small cell lung cancer (NSCLC) patients was observed. Furthermore, ELISA analysis showed that the plasma level of IDH1 was significantly elevated in NSCLC patients compared with benign lung disease patients and healthy individuals. In addition, knockdown of IDH1 by RNA interference suppressed the proliferation of NSCLC cell line and decreased the growth of xenograft tumors in vivo. These observations suggested that IDH1, as a protein promoting tumor growth, could be used as a plasma biomarker for diagnosis and a histochemical biomarker for prognosis prediction of NSCLC.
TP53, encoding p53, is one of the most famous tumor suppressor genes. The majority of human cancers demonstrate the inactivation of the p53 pathway. Mutant p53 not only, no longer, functions as a tumor suppressor but can also exert tumor-promoting effects. The basic function of p53 is to respond to cellular stress. We herein review the recent advances in p53 research and focus on apoptosis, cell cycle arrest, and senescence in response to stress. We also review the clinical applications of p53-based therapy for human cancer.
Purpose: The goal of this study was to determine the incidence of metastatic sites in neuroblastoma and the extent to which metastatic sites correlate with age, tumor biology, and survival.
Patients and Methods: All 648 patients with stage IV and IVS neuroblastoma registered on Children's Cancer Group protocols 3881 and 3891 were analyzed. Metastatic site data were provided by treating institutions and reviewed in patients with central nervous system (CNS), intracranial, lung, or "other" metastases.
Results: The incidence of metastatic sites at diagnosis was 70.5% in bone marrow, 55.7% in bone, 30.9% in lymph nodes, 29.6% in liver, 18.2% in intracranial and orbital sites, 3.3% in lung, and 0.6% in CNS. Event-free survival (EFS) was decreased in patients with bone, bone marrow, CNS, intracranial/ orbital, lung, and pleural metastases, and improved in those with liver and skin metastases. In infants, MYCN amplification and unfavorable Shimada histopathology correlated with increased frequencies of bone and intracranial or orbital metastases. In older patients, MYCN amplification correlated with
increased frequencies of intracranial or orbital, liver, and lung metastases. Multivariate analysis revealed that metastatic site is not an independent prognostic factor.
Conclusions: Metastatic pattern in neuroblastoma differs with age and correlates with tumor biological features and EFS. These correlations could reflect changes in host or tumor biological features with age resulting in differences in metastatic capacity or tumor affinity for specific sites.
(C) 1999 Lippincott Williams & Wilkins, Inc.
To better understand the involvement of retinal Müller glial (RMG) cells in retinal diseases, we phenotyped primary porcine RMGs in dependence of cultivation time using different quantitative proteomic strategies. A well-established LC-MS/MS-based quantification method was employed: stable isotope labeling by amino acids in cell culture (SILAC) and directly compared to label-free (LF) quantifications, based on total peak intensities using two different programs (MaxQuant and Progenesis LC-MS). The overall numbers of detected proteins were largely similar (overlap of 1324 proteins), only a total of 173 proteins were significantly altered between the different culture conditions. However, among these, only 21 proteins were shared between the three analytical strategies. Hence, the majority of altered proteins only reached significance thresholds in one of the applied analyses with a larger overlap between the two LF approaches. Among the shared, differentially abundant proteins were known RMG markers as well as new proteins associated with glial cell transition. However, proteins correlated to cellular transitions and dedifferentiation were also found among the proteins only significant in one or two of the applied strategies. Consequently, the application of different quantification and analytical strategies could increase the analytical depths of proteomic phenotyping.
Neuroblastoma is the most common extracranial solid tumor of childhood. This tumor is characterized by poor survival, especially when it features amplification of the MYCN oncogene. The ability for human cancers to propagate is marked by their ability to invade and metastasize to distant sites. Focal adhesion kinase (FAK) is a key tyrosine kinase involved in the survival and metastasis of a number of human tumor types. We have shown that FAK is present in human neuroblastoma and that its expression in neuroblastoma is related to the MYCN oncogene. We have also demonstrated that inhibition of FAK in neuroblastoma leads to decreased tumor cell survival. The current review addresses the relationship between the MYCN oncogene, focal adhesion kinase and neuroblastoma.
Despite significant research on the role of inflammation and immunosurveillance in the immunologic microenvironment of tumors, little attention has been given to the oncogenic capabilities of the complement cascade. The recent finding that complement may contribute to tumor growth suggests an insidious relationship between complement and cancer, especially in light of evidence that complement facilitates cellular proliferation and regeneration. We address the hypothesis that complement proteins promote carcinogenesis and suggest mechanisms by which complement can drive the fundamental features of cancer. Evidence shows that this diverse family of innate immune proteins facilitates dysregulation of mitogenic signaling pathways, sustained cellular proliferation, angiogenesis, insensitivity to apoptosis, invasion and migration, and escape from immunosurveillance. Given that the traditionally held functions for the complement system include innate immunity and cancer defense, our review suggests a new way of thinking about the role of complement proteins in neoplasia.