VEGFA and neoplasm: In addition, pro-angiogenic molecules secreted by tumor cells under hypoxic conditions, including vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and MMPs, can activate their receptors on the surface of ECs and trigger angiogenesis (Harris, 2002; Pugh and Ratcliffe, 2003; Vaupel, 2004).