Similarly, the inactivation of the von Hippel-Lindau factor, whether hereditary or sporadic, results in the activation of hypoxia-inducible factor 2α (HIF-2α) (21), which chronically stimulates the erythropoietin (EPO) cell, being the cell of origin of the most prevalent type of renal cancer (clear cell renal cell cancer) (22). Here, EPO is linked to clear cell renal carcinoma.