ANGPT2 and neoplasm: Dysregulated tumor-associated angiogenesis is orchestrated by a variety of molecular players, such as vascular endothelial growth factor (VEGF), interleukin 8 (IL-8), pleiotrophin, angiopoietin-1, angiopoietin-2, platelet-derived growth factor (PDGF), fibroblast growth factor (FGF)-2, and transforming growth factor beta-1 (TGFβ-1).