EPO and renal carcinoma: 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).