We also observed PDHA1, PDHB, FDX1, GLS, DLD, DLAT, LIAS and LIPT1 were down-regulated in ccRCC tumor tissues, while CDKN2A exhibited higher protein expression among tumor samples in CPTAC-ccRCC database (Figure 2D). This evidence concerns the gene CDKN2A and nonpapillary renal cell carcinoma.