The clinical significance of methylation of MAGE-A1 and-A3 promoters and expression of DNA methyltransferase in patients with laryngeal squamous cell carcinoma

Gene Expression Profiles of Methyltransferases and Demethylases Associated with Metastasis, Tumor Invasion, CpG73 Methylation, and HPV Status in Head and Neck Squamous Cell Carcinoma

Epigenetic studies on the role of DNA-modifying enzymes in HNSCC tumorigenesis have focused on a single enzyme or a group of enzymes. To acquire a more comprehensive insight into the expression profile of methyltransferases and demethylases, in the present study, we examined the mRNA expression of the DNA methyltransferases DNMT1, DNMT3A, and DNMT3B, the DNA demethylases TET1, TET2, TET3, and TDG, and the RNA methyltransferase TRDMT1 by RT-qPCR in paired tumor-normal tissue samples from HNSCC patients. We characterized their expression patterns in relation to regional lymph node metastasis, invasion, HPV16 infection, and CpG73 methylation. Here, we show that tumors with regional lymph node metastases (pN+) exhibited decreased expression of DNMT1, 3A and 3B, and TET1 and 3 compared to non-metastatic tumors (pN0), suggesting that metastasis requires a distinct expression profile of DNA methyltransferases/demethylases in solid tumors. Furthermore, we identified the effect of perivascular invasion and HPV16 on DNMT3B expression in HNSCC. Finally, the expression of TET2 and TDG was inversely correlated with the hypermethylation of CpG73, which has previously been associated with poorer survival in HNSCC. Our study further confirms the importance of DNA methyltransferases and demethylases as potential prognostic biomarkers as well as molecular therapeutic targets for HNSCC.

Circular RNA ciRS-7 promotes laryngeal squamous cell carcinoma development by inducing TGM3 hypermethylation via miR-432-5p/DNMT3B axis

OBJECTIVE

This work is to explore the mechanism by which circular RNA ciRS-7 affects laryngeal squamous cell carcinoma (LSCC).

METHODS

ciRS-7 expression in LSCC tissues was detected by qRT-PCR, and the association between ciRS-7 with clinicopathological features of LSCC patients was evaluated. HN-4 and UM-SCC-10A cells were transfected or cotransfected with si-ciRS-7, miR-432-5p inhibitor, LV-DNMT3B or si-TGM3. Then, the viability and aggressive nature of the cells were tested. The binding site between ciRS-7 and miR-432-5p or between miR-432-5p and DNMT3B was predicted and the targeting relationship was identified. The specific binding between ciRS-7 and miR-432-5p was further verified by AGO2 RIP assay. HN-4 cells transfected with si-ciRS-7 was injected into nude mice to induce xenograft tumors.

RESULTS

Higher ciRS-7 expression in LSCC tissues was closely associated with higher clinical stage, and exacerbated infiltration and lymph node metastasis in LSCC patients. Silencing ciRS-7 inhibited LSCC cell viability, epithelial-mesenchymal transition (EMT), and promoted the apoptosis. When miR-432-5p was inhibited or DNMT3B was overexpressed, the growth and EMT of LSCC cells were stimulated despite ciRS-7 silencing. Downregulation of ciRS-7 restrained the growth of xenograft tumors in vivo.

CONCLUSION

ciRS-7 promotes the progression of LSCC through increasing TGM3 methylation via miR-432-5p/DNMT3B axis.

Comprehensive Analysis to Identify MAGEA3 Expression Correlated With Immune Infiltrates and Lymph Node Metastasis in Gastric Cancer

Gastric cancer (GC) is an aggressive malignant tumor and causes a significant number of deaths every year. With the coming of the age of cancer immunotherapy, search for a new target in gastric cancer may benefit more advanced patients. Melanoma-associated antigen-A3 (MAGEA3), one of the members of the cancer-testis antigen (CTA) family, was considered an important part of cancer immunotherapy. We evaluate the potential role of MAGEA3 in GC through the TCGA database. The result revealed that MAGEA3 is upregulated in GC and linked to poor OS and lymph node metastasis. MAGEA3 was also correlated with immune checkpoints, TMB, and affected the tumor immune microenvironment and the prognosis of GC through CIBERSORT, TIMER, and Kaplan-Meier plotter database analysis. In addition, GSEA-identified MAGEA3 is involved in the immune regulation of GC. Moreover, the protein-protein interaction (PPI) networks of MAGEA3 were constructed through STRING database and MAGEA3-correlated miRNAs were screened based on the joint analysis of multiple databases. In terms of experimental verification, we constructed pET21a (+)/MAGEA3 restructuring plasmids and transformed to Escherichia coli Rosetta. MAGEA3 protein was used as an antigen after being expressed and purified and can effectively detect the specific IgG in 93 GC patients' serum specimens with 44.08% sensitivity and 92.54% specificity. Through further analysis, the positive rate of MAGEA3 was related to the stage and transfer number of lymph nodes. These results indicated that MAGEA3 is a novel biomarker and correlated with lymph node metastasis and immune infiltrates in GC, which could be a new target for immunotherapy.

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.

Increased Expression of DNA Methyltransferase 1 and 3B Correlates with Tumor Grade in Laryngeal Squamous Cell Carcinoma

Background: DNA methyltransferase (DNMT) enzymes, encoded by DNMT1, DNMT3A andDNMT3B genes, play a major role in the development of cancers through aberrant promotermethylation. Due to little information about the biological and clinical significance of expressionchanges of these genes in Laryngeal Squamous Cell carcinoma (LSCC), the current study wasdesigned to evaluate the contribution of DNMTs expression as potential diagnostic biomarkersin progression of LSCC. Methods: DNMT1, DNMT3A and DNMT3B expressions in tumoral and normal tissues fromthirty-three LSCC patients were evaluated by relative comparative real-time PCR, prior toany therapeutic intervention. Relationship between genes expression and clinicopathologicalfeatures were also analyzed. Results: The mRNA expression levels of all three DNMTs (DNMT1, DNMT3A and DNMT3B)were significantly elevated in LSCC tumor specimens compared to that of non-tumor tissues(P<0.0001, P=0.011 and P<0.0001, respectively). The expression of DNMT1 and DNMT3Bwas strongly associated with histopathological tumor grade. Moreover, the mRNA expressionlevels of DNMT3A were significantly correlated with laryngopharyngeal reflux. No significantrelationships existed with other clinicopathological parameters. Conclusion: Data showed that the expression levels of DNMT1, DNMT3A and DNMT3Bmarkedly increased in LSCC tissues. DNMT1 and DNMT3B were mainly overexpressed in highgrade LSCC tumors, therefore, they may have a role in LSCC progression. It seems that thesegenes may serve as diagnostic biomarkers in development of LSCC.

Development and validation of a novel metabolic signature for predicting prognosis in patients with laryngeal cancer

PURPOSE

Despite advances in the development of treatments for laryngeal cancer (LC), including surgical treatments and radio-chemotherapy, the survival rate of LC remains low. Therefore, novel metabolic signatures are urgently needed to evaluate the prognosis of LC patients.

METHODS

Differentially expressed metabolic genes were extracted via bioinformatics analysis from the raw data of The Cancer Genome Atlas and Gene Expression Omnibus (GEO) databases. Univariate Cox regression and LASSO analyses were performed to identify metabolic genes that were significantly correlated with overall survival (OS). Using the Kaplan-Meier analysis and receiver operating characteristics, the prognostic power of candidate signatures was evaluated in the two databases. Gene Set Enrichment Analysis (GSEA) was performed to explore significant signaling pathways and underlying mechanisms in the high- and low-risk groups.

RESULTS

Thirteen metabolism genes showed superior ability to predict OS for LC when compared to clinical variables, and patients in the high-risk group showed significantly poorer OS than those in the low-risk group. The area under the curve of receiver operating curves for 5- and 3-year OS was 0.929 and 0.899, respectively, which were better than the OS obtained with clinicopathological variables. Similar results obtained in the GEO cohort indicated that this gene signature could differentiate between LC patients with and without recurrence.

CONCLUSION

To our knowledge, this study is the first to report that the 13 metabolic genes could serve as an independent biomarker for LC, which could provide vital prognostic information and prediction for personalized treatment of LC.