EPAS1 and nonpapillary renal cell carcinoma: One of the main oncogenic drivers of ccRCC is loss of function of the von Hippel–Lindau (VHL) gene, which results in a continuous downstream activation of hypoxia-induced factors (HIFs) such as HIF-2α and subsequent overexpression of hypoxia-induced genes such as the pro-angiogenic vascular endothelial growth factor (VEGF) [2].