HIF1A and nonpapillary renal cell carcinoma: In considering the genetic alteration levels, mutations in the Von Hippel-Lindau (VHL) gene, which acts as tumour suppressor gene by stabilizing hypoxia inducible factors (HIF-1α and HIF-2α) and the polybromo-1 (PBRM1) gene, which are associated with chromatin remodelling are the most common alterations in ccRCC.