VEGFA and neoplasm: Rapid proliferating tumor cells generally generate a mass which lacks oxygen (hypoxia) and this physical condition stabilizes HIFs to trigger a series of downstream gene expression, including genes for vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), angiopoietins and stromal derived factor-1α (SDF-1α)6, thus leading to angiogenesis.