ANGPT1 and neoplasm: The most important pro-angiogenic factor is vascular endothelial growth factor receptor (VEGFR), but other factors also contribute to tumor angiogenesis, such as fibroblast growth factor receptor (FGFR), angiopoietins 1 and 2 (Ang1 and Ang2), erythropoietin (EP), transforming growth factor beta (TGF-β), and matrix metalloproteinases (MMPs) [4].