CA9 and nonpapillary renal cell carcinoma: In order to know whether the hMOF is involved in the pathogenesis of primary RCC or not, we first examined the mRNA levels of hMOF and other hypoxia signature genes including CA9, VEGF and HIF1α in 4 random cases of newly diagnosed ccRCC (Figure 1A) by reverse transcription PCR (RT-PCR) and quantitative real-time PCR (qPCR).