FDX1 and nonpapillary renal cell carcinoma: In line with this, IHC staining of ccRCC tissue micro-array (27/62 cRCC with paired adjacent kidney tissues) also confirmed the decreased expression of FDX1 in ccRCC (Figure 4B, n = 27), suggesting that FDX1 may serve as a tumor-suppressive regulator in ccRCC development.