VEGFA and neoplasm: Synergy between anti-PD-1 therapy and antiangiogenesis may be explained by immune cells entering tumor tissues, normal vascular endothelium ensuring targeting of the tumor vasculature to enhance T-cell activity, and tumor angiogenesis helping tumor cells escape immune attack through cytokines such as vascular endothelial growth factor (VEGF), prostaglandin E2, interleukin- (IL-) 10, and local tumor hypoxia.