Hypoxic tumor cells, macrophages, and other cells of the immune system, stimulate the production of hypoxia-inducible factor 1 α (HIF-1 α) which induces upregulation of angiogenic factors such as VEGF, FGF, PDGF, and TGF-β, causing blood vessel growth, increase in vascular permeability and release of proteases, important for cancer cell invasion and metastatic dissemination [149]. The gene discussed is TGFB1; the disease is neoplasm.