PRDX4 and nonpapillary renal cell carcinoma: The increased expression of majority of validated upregulated genes (n = 5, except HIG2 and RNF149), correlated with the expression of VHL, HIF1A, and EPAS1, with highest correlation coefficient for FUT11 (0.71), EGLN3 (0.60), PFKP (0.58), and NDUFA4L2 (0.48), and lowest for PRDX4 (0.39), indirectly suggesting their dependence on VHL, HIF1A, and EPAS1. Further, we investigated if the expression of validated genes could be used as a predictor of disease progression using the same group of 31 ccRCC patients.