PPARGC1A and nonpapillary renal cell carcinoma: Significantly higher mRNA and protein levels of the PGC1A, UCP1 and other markers of lipid browning (CIDEA and DIO2) were detected in the ccRCC cell lines overexpressing NNT,27 while their levels were obviously decreased in the NNT knockdown cells (Figures 4D‐4G).