CCNA2 and nonpapillary renal cell carcinoma: The aim of the present study was to explore the potential role of CCNA2 in tumor proliferation and analyze its correlation with the immune microenvironment in pancancer settings, especially in clear cell renal cell carcinoma (ccRCC) by conducting a comprehensive analysis of CCNA2 using several publicly available databases and inhouse datasets via bioinformatics and experiments.