Prognostic Significance of MAGE-A11 in Esophageal Squamous Cell Carcinoma and Identification of Related Genes Based on DNA Microarray

Cancer/testis antigen expression and co-expression patterns in gastroesophageal adenocarcinoma

Gastroesophageal adenocarcinoma (GEAC) poses a significant challenge due to its poor prognosis and limited treatment options. Recently, Cancer/testis antigens (CTAs) have emerged as potential therapy targets due to their high expression in tumor cells and their immunogenic nature. We aimed to explore the expression and co-expression of CTAs in GEAC. We analyzed 63 GEAC patients initially and validated our findings in 329 patients from The Cancer Genome Atlas (TCGA) database. CTA expression was measured after RNA sequencing, while clinical information, including survival outcomes and treatment details, was collected from an institutional database. Co-expression patterns among CTAs were determined using Spearman correlation analysis. The majority of the study cohort were male (87%), Caucasian (94%), and had stage IV disease (64%). CTAs were highly prevalent, ranging from 58 to 19%. The MAGE gene family showed the highest expression, consistent across both cohorts. The correlation matrix revealed a distinct cluster of significantly co-expressed genes, including MAGEA3, NY-ESO-1, and others (0.27 ≤ r ≤ 0.73). Survival analysis revealed that individual CTAs were associated with poorer survival outcomes in patients not receiving immunotherapy while showing potential for improved survival in those undergoing immunotherapy, although these findings lacked robust reliability. Our study provides a comprehensive characterization of CTA expression and co-expression in GEAC. The strong correlation among CTAs like MAGE, NY-ESO-1, and GAGE suggests a potential for therapies targeting multiple CTAs simultaneously. Further research, including prospective trials, is warranted to assess the prognostic value of CTAs and their suitability as therapeutic targets.

Cancer/testis antigen expression and co-expression patterns in Gastroesophageal Adenocarcinoma

Gastroesophageal adenocarcinoma (GEAC) poses a significant challenge due to its poor prognosis and limited treatment options. Recently, Cancer/testis antigens (CTAs) have emerged as potential therapy targets due to their high expression in tumor cells and their immunogenic nature. We aimed to explore the expression and co-expression of CTAs in GEAC. We analyzed 63 GEAC patients initially and validated our findings in 329 patients from The Cancer Genome Atlas (TCGA) database. CTA expression was measured after RNA sequencing, while clinical information, including survival outcomes and treatment details, was collected from an institutional database. Co-expression patterns among CTAs were determined using Pearson correlation analysis. The majority of the study cohort were male (87%), Caucasian (94%), and had stage IV disease (64%). CTAs were highly prevalent, ranging from 58-19%. The MAGE gene family showed the highest expression, consistent across both cohorts. The correlation matrix revealed a distinct cluster of significantly co-expressed genes, including MAGEA3, NY-ESO-1, and others (0.27 ≤ r ≤ 0.73). Survival analysis revealed that individual CTAs were associated with poorer survival outcomes in patients not receiving immunotherapy while showing potential for improved survival in those undergoing immunotherapy, although these findings lacked robust reliability. Our study provides a comprehensive characterization of CTA expression and co-expression in GEAC. The strong correlation among CTAs like MAGE, NY-ESO-1, and GAGE suggests a potential for therapies targeting multiple CTAs simultaneously. Further research, including prospective trials, is warranted to assess the prognostic value of CTAs and their suitability as therapeutic targets.

MAGE-A11 is a potential prognostic biomarker and immunotherapeutic target in gastric cancer

Gastric cancer poses a serious threat to human health and affects the digestive system. The lack of early symptoms and a dearth of effective identification methods make diagnosis difficult, with many patients only receiving a definitive diagnosis at a malignant stage, causing them to miss out on optimal therapeutic interventions. Melanoma-associated antigen-A (MAGE-A) is part of the MAGE family and falls under the cancer/testis antigen (CTA) category. The MAGE-A subfamily plays a significant role in tumorigenesis, proliferation and migration. The expression, prognosis and function of MAGE-A family members in GC, however, remain unclear. Our research and screening have shown that MAGE-A11 was highly expressed in GC tissues and was associated with poor patient prognosis. Additionally, MAGE-A11 functioned as an independent prognostic factor in GC through Cox regression analysis, and its expression showed significant correlation with both tumour immune cell infiltration and responsiveness to immunotherapy. Our data further indicated that MAGE-A11 regulated GC cell proliferation and migration. Subsequently, our findings propose that MAGE-A11 may operate as a prognostic factor, having potential as an immunotherapy target for GC.

Diagnostic performance of anti-MAGEA family protein autoantibodies in esophageal squamous cell carcinoma

MAGEA family proteins are immunogenic and can produce corresponding autoantibodies, and we aim to evaluate the diagnostic value of anti-MAGEA family protein autoantibodies in esophageal squamous cell carcinoma (ESCC). Protein chip was used to detect the expression level of anti-MAGEA autoantibodies (IgG and IgM) in 20 mixed serum samples. Enzyme linked immunosorbent assay was adopted to determine the expression level of autoantibodies in 1019 serum samples (423 ESCC, 423 healthy control (HC), 173 benign esophageal disease (BED)), and stepwise logistic regression analysis was used for developing a diagnostic model. Eight anti-MAGEA autoantibodies were screened out based on the protein chip. The levels of 7 autoantibodies (MAGEA1-IgG, MAGEA3-IgG, MAGEA3-IgM, MAGEA4-IgG, MAGEA6-IgG, MAGEA10-IgG, MAGEA12-IgG) in ESCC were significantly higher than that in HC, and the levels of anti-MAGEA1 IgG, anti-MAGEA3-IgG, anti-MAGEA4-IgG, anti-MAGEA10-IgG and anti-MAGEA12-IgG autoantibodies in ESCC group were significantly higher than those in BED group. The area under curve (AUC), sensitivity and specificity of the logistic regression model (MAGEA1-IgG, MAGEA4-IgG, MAGEA6-IgG, MAGEA12-IgG) in the training set and the validation set were 0.725 and 0.698, 55.2% and 51.8%, 80.4% and 84.5%, respectively, in distinguishing ESCC and HC. The model also could distinguish between ESCC and BED, with the AUC of 0.743, sensitivity of 55.4% and specificity of 89.0%. The positive rate of the model combined with cytokeratin 19 fragment to diagnose ESCC reached 78.0%. The study identified anti-MAGEA autoantibodies with potential diagnostic value for ESCC, which may provide new promising for the detection of the disease.

Metastasis-Related Signature for Clinically Predicting Prognosis and Tumor Immune Microenvironment of Osteosarcoma Patients

Osteosarcoma is the most prevalent clinical malignant bone tumor in adolescents. The prognosis of metastatic osteosarcoma is still very poor. The aim of our study was to investigate the clinical diagnosis and prognostic significance of metastasis related genes (MRGs) in patients with osteosarcoma. Clinical information and RNA sequencing data with osteosarcoma patients were obtained and set as the training set from UCSC databases. GSE21257 were downloaded and chosen as the verification cohort. An eight gene metastasis related risk signature including MYC, TAC4, ABCA4, GADD45GIP1, TNFRSF21, HERC5, MAGEA11, and PDE1B was built to predict the overall survival of osteosarcoma patients. Based on risk assessments, patients were classified into high- and low-risk groups. The high-risk patients had higher risk score and shorter survival time. ROC curves revealed that this risk signature can accurately predict survival times of osteosarcoma patients at the 1-, 2-, 3-, 4- and 5- year. GSEA revealed that MYC targets, E2F targets, mTORC1 signaling, Wnt /β-catenin signaling and cell cycle were upregulated, and cell adhesion molecules, and primary immunodeficiency were decreased in high-risk group. MRGs were highly linked with the tumor immune microenvironment and ICB response. These results identified that MRGs as a novel prognostic and diagnostic biomarker in osteosarcoma.

Roles of oncogenes in esophageal squamous cell carcinoma and their therapeutic potentials

Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer (EC) in Asia. It is a malignant digestive tract tumor with abundant gene mutations. Due to the lack of specific diagnostic markers and early cancer screening markers, most patients are diagnosed at an advanced stage. Genetic and epigenetic changes are closely related to the occurrence and development of ESCC. Here, We review the activation of proto-oncogenes into oncogenes through gene mutation and gene amplification in ESCC from a genetic and epigenetic genome perspective, We also discuss the specific regulatory mechanisms through which these oncogenes mainly affect the biological function and occurrence and development of ESCC through specific regulatory mechanisms. In addition, we summarize the clinical application value of these oncogenes is summarized, and it provides a feasible direction for clinical use as potential therapeutic and diagnostic markers.

circRNA: A New Biomarker and Therapeutic Target for Esophageal Cancer

Circular RNAs (circRNAs) comprise a large class of endogenous non-coding RNA with covalently closed loops and have independent functions as linear transcripts transcribed from identical genes. circRNAs are generated by a “back-splicing” process regulated by regulatory elements in cis and associating proteins in trans. Many studies have shown that circRNAs play important roles in multiple processes, including splicing, transcription, chromatin modification, miRNA sponges, and protein decoys. circRNAs are highly stable because of their closed ring structure, which prevents them from degradation by exonucleases, and are more abundant in terminally differentiated cells, such as brains. Recently, it was demonstrated that numerous circRNAs are differentially expressed in cancer cells, and their dysfunction is involved in tumorigenesis and metastasis. However, the crucial functions of these circRNAs and the dysregulation of circRNAs in cancer are still unknown. In this review, we summarize the recent reports on the biogenesis and biology of circRNAs and then catalog the advances in using circRNAs as biomarkers and therapeutic targets for cancer therapy, particularly esophageal cancer.

Pathogenicity of the MAGE family

The melanoma antigen gene (MAGE) protein family is a group of highly conserved proteins that share a common homology domain. Under normal circumstances, numerous MAGE proteins are only expressed in reproduction-related tissues; however, abnormal expression levels are observed in a variety of tumor tissues. The MAGE family consists of type I and II proteins, several of which are cancer-testis antigens that are highly expressed in cancer and serve a critical role in tumorigenesis. Therefore, this review will use the relationship between MAGEs and tumors as a starting point, focusing on the latest developments regarding the function of MAGEs as oncogenes, and preliminarily reveal their possible mechanisms.

Prognostic Value of Melanoma-Associated Antigen-A (MAGE-A) Gene Expression in Various Human Cancers: A Systematic Review and Meta-analysis of 7428 Patients and 44 Studies

Background

Members of the melanoma-associated antigen-A (MAGE-A) subfamily are overexpressed in many cancers and can drive cancer progression, metastasis, and therapeutic recurrence.

Objective

This study is the first comprehensive meta-analysis evaluating the prognostic utility of MAGE-A members in different cancers.

Methods

A systematic literature search was conducted in PubMed, Google Scholar, Science Direct, and Web of Science. The pooled hazard ratios with 95% confidence intervals were estimated to evaluate the prognostic significance of MAGE-A expression in various cancers.

Results

In total, 44 eligible studies consisting of 7428 patients from 11 countries were analysed. Univariate and multivariate analysis for overall survival, progression-free survival, and disease-free survival showed a significant association between high MAGE-A expression and various cancers (P < 0.00001). Additionally, subgroup analysis demonstrated that high MAGE-A expression was significantly associated with poor prognosis for lung, gastrointestinal, breast, and ovarian cancer in both univariate and multivariate analysis for overall survival.

Conclusion

Overexpression of MAGE-A subfamily members is linked to poor prognosis in multiple cancers. Therefore, it could serve as a potential prognostic marker of poor prognosis in cancers.

Electronic supplementary material

The online version of this article (10.1007/s40291-020-00476-5) contains supplementary material, which is available to authorized users.

Epigenetic modulation combined with PD-1/PD-L1 blockade enhances immunotherapy based on MAGE-A11 antigen-specific CD8+T cells against esophageal carcinoma

Cancer testis antigens (CTAs) are promising targets for T cell-based immunotherapy and studies have shown that certain CT genes are epigenetically depressed in cancer cells through DNA demethylation. Melanoma-associated antigen A11 (MAGE-A11) is a CTA that is frequently expressed in esophageal cancer and is correlated with a poor esophageal cancer prognosis. Consequently, MAGE-A11 is a potential immunotherapy target. In this study, we evaluated MAGE-A11 expression in esophageal cancer cells and found that it was downregulated in several tumor cell lines, which restricted the effect of immunotherapy. Additionally, the specific recognition and lytic potential of cytotoxic T lymphocytes (CTLs) derived from the MAGE-A11 was determined. Specific CTLs could kill esophageal cancer cells expressing MAGE-A11 but rarely lysed MAGE-A11-negative tumor cells. Therefore, induction of MAGE-A11 expression is critical for CTLs recognition and lysis of esophageal cancer cells. Treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine increased MAGE-A11 expression in esophageal cancer cells and subsequently enhanced the cytotoxicity of MAGE-A11-specific CD8+T cells against cancer cell lines. Furthermore, we found that PD-L1 expression in esophageal cancer cells affected the antitumor function of CTLs. programmed death-1 (PD-1)/PD-L1 blockade could increase the specific CTL-induced lysis of HLA-A2+/MAGE-A11+ tumor cell lines treated with 5-aza-2'-deoxycytidine. These findings indicate that the treatment of tumor cells with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine augments MAGE-A11 expression in esophageal cancer cells. The combination of epigenetic modulation by 5-aza-2'-deoxycytidine and PD-1/PD-L1 blockade may be useful for T cell-based immunotherapy against esophageal cancer.

Distribution and prognostic impact of M1 macrophage on esophageal squamous cell carcinoma

Macrophages are a double-edged sword with potential cancer-promoting and anticancer effects. Controversy remains regarding the effect of macrophages, especially M1 macrophages, on tumor promotion and suppression. We aimed to investigate the role of M1 macrophages in the occurrence and progression of esophageal squamous cell carcinoma (ESCC). Analyzing the data in Gene Expression Omnibus database by the CIBERSORT algorithm found that M1 macrophages were one of the important components of many immune cells in ESCCs, and the increase in their number was obviously negatively correlated with tumor T staging. This result was verified by our experimental data: the density of CD68/HLA-DR double-stained M1 macrophages in ESCC tumor nest and tumor stroma was significantly higher than that in cancer-adjacent normal (CAN) tissues. The density of M1 macrophages in ESCC tumor nest was negatively correlated with the patient's lymph node metastasis and clinical stage (P < 0.05), and the negative tendency was more obvious for M1 macrophages in ESCC tumor stroma (P < 0.001). Exposure to M1 macrophage-conditioned medium inhibited ESCC cell migration and invasion ability significantly (P < 0.05). Moreover, the increased M1 macrophage density in ESCC tumor stroma correlated positively with good prognosis of ESCC. M1 macrophages were involved in inhibiting ESCC cell migration and invasion, which could serve as a good prognostic factor in patients with ESCC.

MAGE-A11 Expression Predicts Patient Prognosis in Head and Neck Squamous Cell Carcinoma

Background

Head and neck squamous cell carcinomas (HNSCCs) are the sixth most common cancer worldwide. Growing evidence showed that Melanoma-associated antigen-A11 (MAGE-A11) was abnormally expressed in various malignancies, but MAGE-A11 expression and its biological roles in HNSCC had not been reported in detail. The aim of the study was to investigate the association between MAGE-A11 signatures and clinicopathological features of HNSCC patients and uncover its potential mechanisms in HNSCC patients.

Methods

In the present study, we analyzed the expression of MAGE-A11 gene and evaluated the impact of MAGE-A11 genes expression on clinical outcome from the Cancer Genome Atlas (TCGA) database. MAGE-A11 expression was assessed in a well-characterized series of HNSCC (N = 75) with long-term follow-up and 10 cases of adjacent non-cancerous tissues, which were diagnosed between 2013 and 2014, by using immunohistochemistry. The correlation between MAGE-A11 expression and clinicopathological factors was analyzed. Kaplan-Meier and Cox regression analyses were used to assess the prognostic significance of MAGE-A11 expression among HNSCC patients.

Results

The results showed that MAGE-A11 mRNA expression was increased in HNSCC tissues compared to "normal" tissues (P < 10^-12). MAGE-A11 protein expression was not correlated with lymph node status, relapse, age, gender, histological grade, differentiation, clinical stage, tumor size, radiotherapy or chemotherapy. The patients with high MAGE-A11 expression had lower 5-year overall survival (OS) rates than those with low MAGE-A11 expression as determined using the Kaplan-Meier method. The univariate and multivariate analyses confirmed that elevated MAGE-A11 was an independent prognostic factor for the OS of HNSCC patients.

Conclusion

These findings indicate that MAGE-A11 may be a valuable diagnostic or prognostic marker as well as a potential molecular therapy target for HNSCC patients.

The immune landscape of esophageal cancer

Esophageal cancer (EC) seriously threatens human health, and a promising new avenue for EC treatment involves cancer immunotherapy. To improve the efficacy of EC immunotherapy and to develop novel strategies for EC prognosis prediction or clinical treatment, understanding the immune landscapes in EC is required. EC cells harbor abundant tumor antigens, including tumor-associated antigens and neoantigens, which have the ability to initiate dendritic cell-mediated tumor-killing cytotoxic T lymphocytes in the early stage of cancer development. As EC cells battle the immune system, they obtain an ability to suppress antitumor immunity through immune checkpoints, secreted factors, and negative regulatory immune cells. Cancer-associated fibroblasts also contribute to the immune evasion of EC cells. Some factors of the immune landscape in EC tumor microenvironment are associated with cancer development, patient survival, or treatment response. Based on the immune landscape, peptide vaccines, adoptive T cell therapy, and immune checkpoint blockade can be used for EC immunotherapy. Combined strategies are required for better clinical outcome in EC. This review provides directions to design novel and effective strategies for prognosis prediction and immunotherapy in EC.

miR-92b-3p Functions As A Key Gene In Esophageal Squamous Cell Cancer As Determined By Co-Expression Analysis

Background

Esophageal squamous cell carcinoma (ESCC) is a highly aggressive malignancy. The aims of the present study were to screen the critical miRNA and corresponding target genes that related to development of ESCC by weighted gene correlation network analysis (WGCNA) and investigate the functions by experimental validation.

Methods

Datasets of mRNA and miRNA expression data were downloaded from GEO. The R software was used for data preprocessing and differential expression gene analysis. The differentially expressed protein-coding genes (DEGs) and miRNAs (DEMs) were selected (FDR <0.05 or |Fold Change (FC)| >1.5). Meanwhile, 81 expression data of ESCC patients in TCGA combined with clinic information were applied by WGCNA to create networks. The correlational analyses between each module and clinical parameters were conducted, and enrichment analyses of GO and KEGG were subsequently performed. Then, a series of experiments were conducted in ESCC cells by use of miRNA mimics.

Results

In total, 4,023 DEGs and 328 DEMs were screened. After checking good genes and samples, 3,841 genes (3,696 DEGs and 145 DEMs) were used for WGCNA. As a consequence, altogether 11 gene modules were found. Among them, the brown modules were found to be strongly inversely associated with pathological grade. Meanwhile, has-mir-92b, the only miRNA in brown module, had a positive correlation with grade and negatively correlated with potential target gene (KFL4 and DCS2) in the same module. Furthermore, an increased expression of miR-92b-3p and down-regulated KLF4 and DSC2 protein was detected in the ESCC clinical samples. Up-regulated miR-92b-3p shortened G0/G1 phase and promote ESCC cells invasion and migration. Furthermore, we verified that DSC2 and KFL4 was target genes of miR-92b-3p by luciferase report assay.

Conclusion

WGCNA is an efficient approach to system biology. By this procedure, miR-92b-3p was identified as an ESCC-promoting gene by target KLF4 and DCS2.

Demethylation-mediated upregulation of melanoma-associated antigen-A11 correlates with malignant progression of esophageal squamous cell carcinoma

BACKGROUND

The expression and methylation status of oncogenes are closely related to the onset and progression of cancer.

AIMS

To explore the role and methylation status of melanoma-associated antigen-A11 in the pathogenesis of esophageal squamous cell carcinoma.

METHODS

116 esophageal squamous cell carcinoma patients with tumor tissues and corresponding adjacent normal tissues were obtained. The expression level and methylation status of melanoma-associated antigen-A11 in esophageal cancer cell lines and esophageal squamous cell carcinoma tissues were determined respectively.

RESULTS

Significant up-regulation of melanoma-associated antigen-A11 was detected in esophageal cancer cell lines and esophageal squamous cell carcinoma tissues. Up-regulation of melanoma-associated antigen-A11 contributed to proliferation and invasion in cancer cells. Hypomethylation of the CpG site was associated with pathological differentiation, clinical stage, tumor size, lymph node metastasis and distant metastasis. Esophageal squamous cell carcinoma patients in stage III and IV, with high expression of melanoma-associated antigen-A11 or hypomethylation of the CpG site within the promoter demonstrated poor survival.

CONCLUSION

Melanoma-associated antigen-A11 is up-regulated in esophageal squamous cell carcinoma at least partly by hypomethylation of the CpG site within the promoter and this hypomethylation may affect the prognosis of esophageal squamous cell carcinoma patients.

Analysis of the function of MAGE-A in esophageal carcinoma by bioinformatics

BACKGROUND

Melanoma-associated antigen-A (MAGE-A) was recognized as high-expressed in many solid tumors including esophageal carcinoma (EC), nevertheless, was reported to be low/not-expressed in normal tissues. Thus, it was considered as an extraordinary appropriate target for treatment especially in immunotherapy. Therefore, it demanded more detail knowledge on the precise function of MAGE-A.

METHODS

In this study, we used the data from the Cancer Genome Atlas dataset (TCGA-ESCA) to analyze the expression and survival for MAGE A3/4/11 (the subtype of MAGE-A) using the online tool of UALCAN. Furthermore, the high-throughput sequencing data of the patients with esophageal squamous-cell carcinoma (ESCC) from TCGA dataset were performed to analyze the correlation test, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of MAGE A3/4/9/11 using LinkeDomics (online tool) and ClueGO (inner software of Cytoscape). Finally, relative gene expressions of MAGE A3/4/9/11 were verified by quantitative real-time PCR (q-PCR) in the patients with EC.

RESULTS

MAGE A3/4/11 was high-expressed in tissues of patients with ESCC, and there was no difference in survival time for patients between the high-expressed with the low/medium-expressed. The Go enrichment analysis showed that the 4 MAGE-A subtypes (MAGE-A3/4/9/11) were enriched in the regulation of the adaptive immune response, translational initiation, interleukin-4 production, response to type I interferon, and skin development, respectively. The KEGG results showed that they were enriched in T cell receptor signaling pathway (MAGE-A3), Th1 and Th2 differentiation, antigen processing and presentation (MAGE-A4), cytokine-cytokine receptor interaction (MAGE-A9), and chemokine signaling pathway (MAGE-A11).

CONCLUSION

MAGE A3/4/9/11 was high-expressed in EC, and were enrolled in the regulation of immune response. They may consider as candidate immune target for EC treatment and provided the messages for further research in the function of MAGE-A.

Expression of cancer-testis antigens in esophageal cancer and their progress in immunotherapy

PURPOSE

Esophageal cancer is a common disease in China with low survival rate due to no obvious early symptoms and lack of effective screening strategies. Traditional treatments usually do not produce desirable results in patients with advanced esophageal cancer, so immunotherapy which relies on tumor-related antigens is needed to combat low survival rates effectively. Cancer-testis antigens (CTA), a large family of tumor-related antigens, have a strong in vivo immunogenicity and tumor-restricted expressing patterns in normal adult tissues. These two characteristics are ideal features of anticancer immunotherapy targets and, therefore, promoted the development of some studies of CTA-based therapy. To provide ideas for the role of the cancer-testis antigens MAGE-A, NY-ESO-1, LAGE-1, and TTK in esophageal cancer, we summarized their expression, prognostic value, and development in immunotherapy.

METHODS

The relevant literature from PubMed is reviewed in this study.

RESULTS

In esophageal cancer, although the relationship between expression of MAGE-A, NY-ESO-1, LAGE-1, and TTK and prognosis value is still in a controversial situation, MAGE-A, NY-ESO-1, LAGE-1, and TTK are highly expressed and can induce specific CTL cells to produce particular killing effect on tumor cells, and some clinical trials have demonstrated that immunotherapy for esophageal cancer patients is effective and safe, which provides a new therapeutic strategy for the treatment of esophageal cancer in the future.

CONCLUSION

In this review, we summarize expression and prognostic value of MAGE-A, NY-ESO-1, LAGE-1, and TTK in esophageal cancer and point out recent advances in immunotherapy about them.

Tumor suppressive miR-6775-3p inhibits ESCC progression through forming a positive feedback loop with p53 via MAGE-A family proteins

Accumulating evidences indicate that microRNAs (miRNAs) play vital roles in multiple diseases, including cancer. In the present study, we showed that miR-6775-3p plays a tumor suppressive role in esophageal squamous cell carcinoma (ESCC). High expression miR-6775-3p is associated with good clinical outcomes of ESCC patients. Over-expression of miR-6775-3p inhibited tumor growth and liver metastasis of ESCC xenograft tumors. Enforced expression of miR-6775-3p inhibited ESCC cell proliferation, migration, and invasion. KEGG pathway analysis revealed that miR-6775-3p was associated with the genes on “pathway in cancer”. Mechanically, miR-6775-3p inhibited the expression of tumor antigens MAGE-A family through direct binding the 3′UTR region of MAGE-A mRNAs, and attenuated MAGE-A-inhibited transcriptional activity of tumor suppressor p53. In addition, miR-6775-3p also directly inhibits its host gene SLC7A5 which has been reported to play oncogenic roles in cancer progression. Interestingly, miR-6775-3p and its host gene SLC7A5 were directly transcriptionally induced by p53. Thus, for the first time, our study proposed a novel positive feedback regulation between miR-6775-3p and p53 via MAGE-A family, which plays crucial role in ESCC progression.

Epigenetic regulation of MAGE family in human cancer progression-DNA methylation, histone modification, and non-coding RNAs

The melanoma antigen gene (MAGE) proteins are a group of highly conserved family members that contain a common MAGE homology domain. Type I MAGEs are relevant cancer-testis antigens (CTAs), and originally considered as attractive targets for cancer immunotherapy due to their typically high expression in tumor tissues but restricted expression in normal adult tissues. Here, we reviewed the recent discoveries and ideas that illustrate the biological functions of MAGE family in cancer progression. Furthermore, we also highlighted the current understanding of the epigenetic mechanism of MAGE family expression in human cancers.

Evolution of Melanoma Antigen-A11 (MAGEA11) During Primate Phylogeny

Melanoma antigen-A11 (MAGE-A11) is an X-linked and primate-specific steroid hormone receptor transcriptional coregulator and proto-oncogenic protein whose increased expression promotes the growth of prostate cancer. The MAGEA11 gene is expressed at low levels in normal human testis, ovary, and endometrium, and at highest levels in castration-resistant prostate cancer. Annotated genome predictions throughout the surviving primate lineage show that MAGEA11 acquired three 5' coding exons unique within the MAGEA subfamily during the evolution of New World monkeys (NWM), Old World monkeys (OWM), and apes. MAGE-A11 in all primates has a conserved FXXIF coactivator-binding motif that suggests interaction with p160 coactivators contributed to its early evolution as a transcriptional coregulator. An ancestral form of MAGE-A11 in the more distantly related lemur has significant amino acid sequence identity with human MAGE-A11, but lacks coregulator activity based on the absence of the three 5' coding exons that include a nuclear localization signal (NLS). NWM MAGE-A11 has greater amino acid sequence identity than lemur to human MAGE-A11, but inframe premature stop codons suggest that MAGEA11 is a pseudogene in NWM. MAGE-A11 in OWM and apes has nearly identical 5' coding exon amino acid sequence and conserved interaction sites for p300 acetyltransferase and cyclin A. We conclude that the evolution of MAGEA11 within the lineage leading to OWM and apes resulted in steroid hormone receptor transcriptional coregulator activity through the acquisition of three 5' coding exons that include a NLS sequence and nonsynonymous substitutions required to interact with cell cycle regulatory proteins and transcription factors.

MAGE-A11 is activated through TFCP2/ZEB1 binding sites de-methylation as well as histone modification and facilitates ESCC tumor growth

Recently, we have reported that the product of Melanoma Antigens Genes (MAGE) family member MAGE-A11 is an independent poor prognostic marker for esophageal squamous cell carcinoma (ESCC). However, the reason how MAGE-A11 is activated in ESCC progression still remains unclear. In the current study, we demonstrated that DNA methylation and the subsequent histone posttranslational modifications play crucial roles in the regulation of MAGE-A11 in ESCC progression. We found that the methylation rate of TFCP2/ZEB1 binding site on MAGE-A11 promoter in ESCC tissues and cells is higher than the normal esophageal epithelial tissues and cells. Transcription factors TFCP2 and ZEB1 directly bind MAGE-A11 promoter and regulate the endogenous MAGE-A11 expression in a methylation-dependent manner in ESCC cells. Following MAGE-A11 promoter methylation, the methyl-CpG-binding protein MeCP2 was found to bind the methylated MAGE-A11 promoter to mediate histone deactylation by recruiting HDAC1 and HDAC2. Simultaneously, histone inactivation marks including H3K27me3 as well as H3K9me3 were increased, whereas histone activation mark H3K4me3 was decreased. HDAC inhibitor Trichostatin A (TSA) increased DNA methylase inhibitor Decitabine (DAC)-induced MAGE-A11 expression. siRNA-mediated knockdown of histone methltransferase EZH2 or DZNep (a EZH2 inhibitor) treatment increased DAC-induced MAGE-A11 expression. Our results indicate that MAGE-A11 is activated through DNA demethylation, histone acetylation and histone methylation in ESCC, and its activation promotes ESCC tumor growth.

MAGE-A11 expression contributes to cisplatin resistance in head and neck cancer

OBJECTIVE

The objective of this study is to investigate the roles of melanoma-associated antigens (MAGEs) in the cisplatin treatment of head and neck cancer.

MATERIALS AND METHODS

We assessed the efficacy of cisplatin in a set of four head and neck cancer cell lines using a crystal violet assay. The MAGE-A expression in all cell lines was measured with RT-qPCR. The correlation between MAGE-A expression and cisplatin efficacy was investigated using Spearman's correlation analysis. Furthermore, we established a cell line with stable overexpression of MAGE-A11 and determined influence on proliferation, cisplatin efficacy and cell apoptosis. In this cell line, the effects of cisplatin were assessed using either crystal violet assays or flow cytometry (Annexin V).

RESULTS

For MAGE-A11, we observed the highest correlation (r = 1.000, p = 0.0417) with low cisplatin efficacy. Stable overexpression of MAGE-A11 resulted in no changes in proliferation, but in lower cisplatin cytotoxicity and lower rates of apoptosis. Also, mouse double minute 2 homolog (MDM2) expression was induced by MAGE-A11 overexpression.

CONCLUSION

We provide evidence that MAGE-A11 expression contributes to cisplatin resistance in head and neck cancer.

CLINICAL RELEVANCE

Our study underscores the negative predictive role of MAGE-A11 expression in head and neck cancer.

A Comprehensive Guide to the MAGE Family of Ubiquitin Ligases

Melanoma antigen (MAGE) genes are conserved in all eukaryotes and encode for proteins sharing a common MAGE homology domain. Although only a single MAGE gene exists in lower eukaryotes, the MAGE family rapidly expanded in eutherians and consists of more than 50 highly conserved genes in humans. A subset of MAGEs initially garnered interest as cancer biomarkers and immunotherapeutic targets due to their antigenic properties and unique expression pattern that is primary restricted to germ cells and aberrantly reactivated in various cancers. However, further investigation revealed that MAGEs not only drive tumorigenesis but also regulate pathways essential for diverse cellular and developmental processes. Therefore, MAGEs are implicated in a broad range of diseases including neurodevelopmental, renal, and lung disorders, and cancer. Recent biochemical and biophysical studies indicate that MAGEs assemble with E3 RING ubiquitin ligases to form MAGE-RING ligases (MRLs) and act as regulators of ubiquitination by modulating ligase activity, substrate specification, and subcellular localization. Here, we present a comprehensive guide to MAGEs highlighting the molecular mechanisms of MRLs and their physiological roles in germ cell and neural development, oncogenic functions in cancer, and potential as therapeutic targets in disease.