Exploratory Analysis of Regulated Cell Death-Related Genes as Potential Prognostic Biomarkers in Endometrial Carcinoma.

Objective: This study aims to explore the mechanism of regulated cell death-related genes in the development of endometrial carcinoma. Methods: Endometrial carcinoma-related datasets were yielded via the Cancer Genome Atlas and Gene Expression Omnibus databases, and regulated cell death-related genes were extracted from the literature. Differential expression analysis, weighted gene co-expression network analysis, and protein interaction analysis were performed to identify critical regulated cell death-related genes. Gene set enrichment analysis was used to identify the functional pathways involved in these critical genes. Afterward, the best clustering approach for tumor samples was yielded via consensus clustering analysis, and nomogram prediction models were built. Shiny Methylation Analysis Resource Tool was used to compare the expression levels of CpG methylation probes for critical genes between tumor and normal samples. Spearman correlation analysis was conducted to investigate the relationship between critical genes and various immune features. Eventually, immuno-infiltrative analysis was implemented, and potential therapeutic agents were screened targeting critical genes. The data were analyzed and visualized by R software using different packages. In addition, the expressions of critical genes were validated by quantitative real-time polymerase chain reaction and immunochemistry. Results: Four critical genes, namely GBP2, SLC11A1, P2RX7, and HCLS1, were identified, and they were involved in various functional pathways such as leukocyte-mediated cytotoxicity. There were substantial differences in CpG methylation in GBP2, SLC11A1, and HCLS1 between tumor and normal samples. As for immune features, all critical genes were positively connected with immunosuppressive factors such as TIGIT and most HLA molecules in endometrial carcinoma. The critical genes high/low expression groups of tumor samples showed different immune responses towards PD-1, PD-L1, and CTLA-4 immunotherapy. The infiltration of 24 immune cells, such as effector memory CD8 T cells, was notably different between tumor and normal samples. Based on sensitivity analysis of chemotherapeutic agents, we found the highest positive correlation between SLC11A1 and "BI.2536" and the strongest passive correlation of HCLS1 and GBP2 with "Ribociclib", as well as P2RX7 with "BMS.754807". Quantitative real-time polymerase chain reaction suggested that the expression trends of GBP2, P2RX7, and HCLS1 were consistent with the results of bioinformatic analysis. Conclusions: Regulated cell death-related genes (GBP2, SLC11A1, P2RX7, and HCLS1) may play a role in endometrial carcinoma development, which can provide new ideas for the treatment and prognosis prediction of this disease.