EPAS1 and nonpapillary renal cell carcinoma: In addition, consistent with the observation of HIF1α enhancing invasion/migration in RENCA, microarray analysis of ccRCC tumors classified as ‘H1H2’ (expressing both HIF1α and HIF2α) had a significantly stronger ‘growth factor signaling/motility’ signature than ccRCC tumors classified as ‘H2′ (expressing HIF2α, not HIF1α) (Fig. 3D in29).