Higher eukaryotes include a widely distributed serine/threonine phosphatase called PPP4C (protein phosphatase 4 catalytic subunit). Its function is to preferentially bind to regulatory subunits, forming a complex to carry out its molecular roles. Although its involvement in pancreatic, colorectal carcinoma and breast cancer has been established, the specific role of PPP4C in pan-cancer remains ambiguous. Through pan-cancer analysis, we identified PPP4C as broadly overexpressed and linked to poor outcomes. Our investigation unveiled diverse expression patterns, demonstrating notable correlations between PPP4C expression and tumor prognosis. We further explored the association between PPP4C expression and various immune-related factors, including microsatellite instability (MSI), tumor mutation burden (TMB), the immune microenvironment, immune cell infiltration, and immune checkpoint molecules. Moreover, with the use of the Genomics of Drug Sensitivity in Cancer (GDSC) database, we discovered pharmaceutical compounds that have a strong association with PPP4C. The CancerSEA database analysis revealed that PPP4C exhibited a negative correlation with metastasis in renal cell carcinoma (RCC). The prognostic prediction of RCC was effectively carried out by the risk signature of PPP4C-related metastasis genes (PrMGs), displaying AUC values of 0.728, 0.700, and 0.706 for the one, two, and three years, respectively. Furthermore, there were notable differences in the immunological state between the two risk groups. In conclusion, our research indicates that PPP4C shows promise as a prognostic biomarker, and novel gene signatures related to metastasis can be employed for prognostic prediction in ccRCC. The risk signature based on PrMGs effectively stratifies ccRCC patient prognosis and reveals distinct immune microenvironment characteristics, providing a foundation for future research into targeted strategies.
Zhang et al. (Thu,) studied this question.