CHAC1 and nonpapillary renal cell carcinoma: Through comprehensive analysis of transcriptomic data from ccRCC patients (n=539) in The Cancer Genome Atlas (TCGA) database, the study identified 5 genes with independent prognostic value (ACADSB, CDCA3, CHAC1, MYCN, TFAP2A) from 437 FPTOS-related genes using univariate Cox regression, LASSO regression, and multivariate Cox regression analyses.