The mitosis-related gene OIP5 is a potential biomarker in pan-cancer

OIP5 is found at the centromere and plays an important role in recruiting centromere protein-A (CENP-A) through interacting with Holliday junction recognition protein during cell mitosis. OIP5 is considered to be a cancer-testis specific gene, but its function in tumor development remains unclear. Increased expression of OIP5 has been reported in testis as well as in different cancers; however, the underlying mechanisms remain obscure.

Data were collected from the Genotype-Tissue Expression project, the Cancer Cell Line Encyclopedia, and The Cancer Genome Atlas (TCGA) to analyze the effect of OIP5 in many common cancers. Analyses of the differential expression of OIP5 and its relationships with prognosis, the tumor microenvironment, immune infiltration, immune regulation, neoantigen production, and genomic stability in various cancers were performed using R software.

Expression of OIP5 was significantly increased in 34 common tumor types compared with matched healthy samples; however, no significant increases were observed in pheochromocytoma and paraganglioma or kidney chromophobe. Elevated OIP5 expression predicted dismal overall survival in 14 tumors. The function of OIP5 in tumor-infiltrating immune cells (TIIC) was analyzed, and OIP5 might inhibit TIIC infiltration in the tumor microenvironment; a positive correlation was found in thymoma, while a negative correlation was observed in lung squamous cell carcinoma and lung adenocarcinoma. High OIP5 expression was related to immune regulation and neoantigen production, particularly in terms of the levels of immune regulatory molecules and the number of neoantigens produced in lung adenocarcinoma, uterine corpus endometrial carcinoma, breast cancer, stomach adenocarcinoma, low-grade glioma, and prostate adenocarcinoma. It was also associated with increased cell genome instability in lung adenocarcinoma. Gene set enrichment analysis revealed potential critical effects of OIP5 on the cell cycle, base excision repair, homologous recombination, DNA replication, the p53 signaling pathway, and mismatch repair pathways.

High expression of OIP5 is found in many common tumors and predicts a dismal prognostic outcome. The gene is an important recruitment factor for CENP-A and may promote tumor progression by affecting the tumor immune microenvironment and genomic stability. Therefore, OIP5 can serve as a potential candidate factor to predict cancer prognosis and guide the use of therapeutics.