HIF-1, under hypoxic conditions in tumor cells, activates key components such as VEGF, PDGF-B (platelet-derived growth factor), hepatocyte growth factor, epidermal growth factor, angiopoietin-2, and placental growth factors, due to reduced levels of aKG and increased onco-metabolites such as succinate and fumarate. This evidence concerns the gene HGF and neoplasm.