PDCD1 and cancer: A new weapon against cancer that has elicited durable clinical advances is cancer immunotherapy that inhibits immune-checkpoints; cytotoxic T-lymphocyte–associated protein 4 (CTLA4) or programmed death 1 (PD1) and its ligand, and programmed death 1 ligand (PDL1) has changed the landscape of anticancer treatment (Smyth et al., 2016).