For example, HIF-1α was reported to remain relatively high even in a richly vascularized (oxygen rich) microenvironment in clear cell renal cell carcinoma (ccRCC, sporadic ccRCC cases are often caused by aberrations in the VHL (encode von Hippel–Lindau tumor suppressor protein) gene). The gene discussed is HIF1A; the disease is nonpapillary renal cell carcinoma.