VEGFA and neoplasm: They are affected by the concentration of oxygen and some growth factors which lead to modulation in the regulation of erythropoiesis, angiogenesis, metabolism, pH regulation, cell migration, and tumor invasion [53] by increases in the expression of angiogenic factors, such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and nitric oxide synthase (NOS).