As demonstrated in Figure 4, among 6 significant hub genes, significantly decreased AGPAT9, AQP7, HMGCS2, KLF15, PPARGC1A mRNA expressions were found in ccRCC tissues compared with adjacent normal tissues, while MLXIPL mRNA expression was significantly elevated in tumor samples compared with normal samples. This evidence concerns the gene KLF15 and nonpapillary renal cell carcinoma.