PDCD1 and neoplasm: Vascular endothelial growth factor (VEGF) has been reported to exert not only tumor angiogenesis-inducing activity, but also immunosuppressive activity which can attenuate the antitumor immunity elicited by anti-PD-L1/PD-1 therapy through inhibition of dendritic cell (DC) maturation (9–12) and accumulation of myeloid-derived suppressor cells (MDSCs) (13).