HIF1A and neoplasm: Indeed, p53 targets the subunit HIF-1-α of hypoxia-inducible factor (HIF), necessary for metabolism adaptation, avoiding its proteasomic degradation through murine double minute 2 protein.134 Ablation of p53 increases the expression of HIF-1-α in a hypoxia condition, which in turn induces the expression of vascular endothelial growth factor (VEGF) in tumor cells and promotes angiogenesis, neovascularization, tumor growth, and invasion.