CA9 and nonpapillary renal cell carcinoma: Among the up-regulated genes in ccRCC, we focused on the five most differentially expressed genes; prolyl hydroxylase 3 (PHD3), fatty acid binding protein 7 (FABP7), carbonic anhydrase IX (CAIX), NADH dehydrogenase 1 alpha subcomplex, 4-like 2 (NDUFA4L2), and monocarboxylate transporter 4 (MCT4).