CA9 and nonpapillary renal cell carcinoma: As such, the expression of CAIX, BNIP3 and phosphoglycerate mutase-1 (PGM1) was elevated exclusively in HIF1α(P-A)2 WT8 cells but not in HIF2α(P-A)2 WT8 cells relative to the control cells (Figure 2A), in line with previous studies showing that these genes are induced by HIF1α in ccRCC cells [27,31,37,38].