TEX19 promotes ovarian carcinoma progression and is a potential target for epitope vaccine immunotherapy

TEX19 increases the levels of CDK4 and promotes breast cancer by disrupting SKP2-mediated CDK4 ubiquitination

BACKGROUND

Globally, breast cancer in women is the fifth leading cause of cancer death. There is an urgent need to explore the molecular mechanism of breast cancer proliferation and metastasis.

METHOD

TCGA database analysis was used to analyze genes expression in breast cancer and normal samples and the association between gene expression and prognosis. Immunohistochemical staining, qPCR and western blotting was sued to detected gene expression. The cell function tests were conducted to investigate the effects of TEX19 and CDK4 with abnormal expression on cell proliferation, migration, apoptosis, cell cycle, and colony formation. Bioinformatics analysis methods combined with CHX tracking experiment and Co-IP experiment were performed to screen and verify the downstream molecule and regulatory mechanism of TEX19. Besides, subcutaneous tumorigenesis model in nude mice was constructed.

RESULTS

TEX19 was significantly upregulated in breast cancer, and the TEX19 level was related to tumor invasion and prognosis. TEX19 knockdown inhibited the proliferation and migration of breast cancer cells, increased cell apoptosis, and blocked the cell cycle in the G2 phase. Besides, TEX19 suppressed the growth of tumors in the body. Mechanically, TEX19 upregulated the level of CDK4 protein, which depended on the E3 ubiquitin ligase SKP2. Specifically, TEX19 knockdown and SKP2 protein overexpression destroyed the stability of CDK4 protein and enhanced the ubiquitination of CDK4 protein. Additionally, CDK4 knockdown inhibited the proliferation, migration, and colony formation of breast cancer cells, and alleviated the promotion of TEX19 overexpression on the proliferation and migration of breast cancer cell.

CONCLUSION

TEX19 and CDK4 were upregulated in breast cancer, and TEX19 increased the level of CDK4 protein by influencing SKP2-mediated ubiquitination of CDK4, thereby promoting the progression of breast cancer.

The potential value of cancer-testis antigens in ovarian cancer: Prognostic markers and targets for immunotherapy

BACKGROUND

Tumor immunotherapy has become an important adjuvant therapy after surgery, radiotherapy, and chemotherapy. In recent years, the role of tumor-associated antigen (TAA) in tumor immunotherapy has become increasingly prominent. Cancer-testis antigen (CTA) is a kind of TAA that is highly restricted in a variety of tumors and can induce an immune response.

AIMS

This review article aimed to evaluate the role of CTA on the progression of ovarian cancer, its diagnostic efficacy, and the potential for immunotherapy.

METHODS

We analyzed publications and outlined a comprehensive of overview the regulatory mechanism, immunogenicity, clinical expression significance, tumorigenesis, and application prospects of CTA in ovarian cancer, with a particular focus on recent progress in CTA-based immunotherapy.

RESULTS

The expression of CTA affects the occurrence, development, and prognosis of ovarian cancer and is closely related to tumor immunity.

CONCLUSION

CTA can be used as a biomarker for the diagnosis and prognosis evaluation of ovarian cancer and is an ideal target for antitumor immunotherapy. These findings provide novel insights on CTA in the improvement of diagnosis and treatment for ovarian cancer. The successes, current challenges and future prospects were also discussed to portray its significant potential.

Transcription Factor FOXA1 Facilitates Glycolysis and Proliferation of Lung Adenocarcinoma via Activation of TEX19

Glycolysis is a shared feature in various cancers including lung adenocarcinoma (LUAD). Testis Expressed 19 (TEX19) is correlated with cancer progression. But its effect on LUAD remains an unanswered question. The focus of our study was primarily to investigate how TEX19 works exactly in LUAD. We first downloaded mRNA data from TCGA-LUAD and performed differential expression analysis. Then, we performed a Kaplan-Meier analysis to analyze the relationship between mRNA expression and patients' prognoses. hTFtarget database was utilized for the prediction of upstream transcription factors of mRNA. Next, qRT-PCR was employed for detecting TEX19 and Forkhead box A1 (FOXA1) expression. Western blot was adopted to detect the expression of glycolysis-related proteins. We also used CCK-8, colony formation, and flow cytometry assays to detect cell viability, proliferation, and apoptosis. Seahorse XF Extracellular Flux Analyzers were introduced to analyze extracellular acidification rate (ECAR) and oxygen consumption rate (OCR). Detection kits were used to detect pyruvate, lactate, citric acid, and malic acid. TEX19 was highly expressed in LUAD tissues. Real-time quantitative PCR (qRT-PCR) assay showed that TEX19 was significantly overexpressed in LUAD cell lines compared with normal bronchial epithelial cells BEAS-2B. Knockdown of TEX19 remarkably inhibited cell activity and proliferation, and promoted cell apoptosis, TEX19 was enriched in the glycolytic pathway. Meanwhile, the knockdown of TEX19 significantly hampered the contents of pyruvate, lactate, citric acid, and malic acid. The bioinformatics analysis, dual luciferase reporter experiment, and chromatin immunoprecipitation (ChIP) assay showed that FOXA1 was bound with TEX19. FOXA1 had a high expression level in LUAD. The rescue assay demonstrated that FOXA1, by activating TEX19 expression, enhanced glycolysis and proliferation and inhibited apoptosis of LUAD cells. In summary, FOXA1 promoted glycolysis and proliferation of LUAD cells by activating TEX19. This result can provide a theoretical basis for future research on LUAD.

In silico modeling of the interaction between TEX19 and LIRE1, and analysis of TEX19 gene missense SNPs

BACKGROUND

Testis expressed 19 (TEX19) is a specific human stem cell gene identified as cancer-testis antigen (CTA), which emerged as a potential therapeutic drug target. TEX19.1, a mouse paralog of human TEX19, can interact with LINE-1 retrotransposable element ORF1 protein (LIRE1) and subsequently restrict mobilization of LINE-1 elements in the genome.

AIM

This study aimed to predict the interaction of TEX19 with LIRE1 and analyze TEX19 missense polymorphisms. TEX19 model was generated using I-TASSER and the interaction between TEX19 and LIRE1 was studied using the HADDOCK software.

METHODS

The stability of the docking formed complex was studied through the molecular dynamic simulation using GROMACS. Missense SNPs (n=102) of TEX19 were screened for their potential effects on protein structure and function using different software.

RESULTS

Outcomes of this study revealed amino acids that potentially stabilize the predicted interaction interface between TEX19 and LIRE1. Of these SNPs, 37 were predicted to play a probably damaging role for the protein, three of them (F35S, P61R, and E55L) located at the binding site of LIRE1 and could disturb this binding affinity.

CONCLUSION

This information can be verified by further in vitro and in vivo experimentations and could be exploited for potential therapeutic targets.

Cancer/testis antigens: from serology to mRNA cancer vaccine

Cancer/testis antigens (CTAs) are a group of tumor antigens expressed in numerous cancer tissues, as well as in the testis and placental tissues. There are over 200 CTAs supported by serology and expression data. The expression patterns of CTAs reflect the similarities between the processes of gametogenesis and tumorigenesis. It is notable that CTAs are highly expressed in three types of cancers (lung cancer, bladder cancer, and skin cancer), all of which have a metal etiology. Here, we review the expression, regulation, and function of CTAs and their translational prospects as cancer biomarkers and treatment targets. Many CTAs are highly immunogenic, tissue-specific, and frequently expressed in cancer tissues but not under physiological conditions, rendering them promising candidates for cancer detection. Some CTAs are associated with clinical outcomes, so they may serve as prognostic biomarkers. A small number of CTAs are membrane-bound, making them ideal targets for chimeric antigen receptor (CAR) T cells. Mounting evidence suggests that CTAs induce humoral or cellular immune responses, providing cancer immunotherapeutic opportunities for T-cell receptors (TCRs), CAR T cell, antibody-based therapy and peptide- or mRNA-based vaccines. Indeed, CTAs are the dominating non-mutated targets in mRNA cancer vaccine development. Clinical trials on CTA TCR and vaccines have shown effectiveness, safety, and tolerance, but these successes are limited to a small number of patients. In-depth studies on CTA expression and function are needed to improve CTA-based immunotherapy.

Peptide-based therapeutic cancer vaccine: Current trends in clinical application

The peptide‐based therapeutic cancer vaccines have attracted enormous attention in recent years as one of the effective treatments of tumour immunotherapy. Most of peptide‐based vaccines are based on epitope peptides stimulating CD8⁺ T cells or CD4⁺ T helper cells to target tumour‐associated antigens (TAAs) or tumour‐specific antigens (TSAs). Some adjuvants and nanomaterials have been exploited to optimize the efficiency of immune response of the epitope peptide to improve its clinical application. At present, numerous peptide‐based therapeutic cancer vaccines have been developed and achieved significant clinical benefits. Similarly, the combination of peptide‐based vaccines and other therapies has demonstrated a superior efficacy in improving anti‐cancer activity. We delve deeper into the choices of targets, design and screening of epitope peptides, clinical efficacy and adverse events of peptide‐based vaccines, and strategies combination of peptide‐based therapeutic cancer vaccines and other therapies. The review will provide a detailed overview and basis for future clinical application of peptide‐based therapeutic cancer vaccines.

Immunotherapy For Ovarian Cancer: Recent Advances And Combination Therapeutic Approaches

Epithelial ovarian cancer (EOC) is the most lethal gynaecological cancer. Although many advances have been made in therapeutic strategies, the global standard of care still remains radical surgery plus chemotherapy, but new scenarios need to be explored to improve survival. The role of immunotherapy in EOC treatment is controversial. Results obtained from studies evaluating immunotherapy are contradictory: in particular data on survival are not as good as expected when immunotherapy was administered alone, and other data are still immature. Thus, significant efforts must be devoted to finding new strategies for the use of immunotherapy. The aim of this paper is to review the most recent findings of the use of immunotherapy in ovarian cancer, with a particular focus on combination approaches.