MDM2 and nonpapillary renal cell carcinoma: Of the eight genes, five were significantly overexpressed in ccRCC relative to normal tissue: CDKN1A (p21) (1.6 fold); CCND1 (cyclin D1) (5.4 fold); MDM2 (1.7 fold); MYC (2.5 fold); and OBFC2A (1.7 fold).