FGF2 and neoplasm: To overcome hypoxia, angiogenesis is promoted by increased expression of hypoxia-inducible factor 1 (HIF-1) [66], VEGF, angiopoietin (ANGPT) 1, ANGPT2 and basic fibroblast growth factor (bFGF), creating an abnormal and dysfunctional vascular network in the tumor (Figure 1) [67].