EPO and neoplasm: Moreover, genes induced by hypoxia, such as VEGF, interleukin 1A (IL-1A), endothelin 1, platelet-derived growth factor B (PDGFB), erythropoietin (EPO), cathepsin, growth arrest and DNA-damage-inducible alpha (GADD45A), and growth arrest and DNA damage-inducible gene 153 (GADD153), as well as the presence of the hypoxia-inducible factor (HIF), are involved in tumor progression and metastasis [113].