HIF1A and nonpapillary renal cell carcinoma: Given that in ccRCC cell lines, HIF2α was generally highly expressed while HIF1α had low or no expression, we overexpressed HIF1α in 786 O and Caki1 cells, and found that FKBP10 expression was suppressed at both the mRNA and protein levels (Fig. 7E, F, S6E).