PDCD1 and neoplasm: For example, combination with taxanes or gemcitabine increases DNA damage and cell cycle arrest, combination with targeted therapies (e.g., EGFR, ALK inhibitors) decreases bypass signaling, and combination with immune checkpoint inhibitors (e.g., anti-PD-1/PD-L1) increases T cell activation and tumor immunogenicity [28,29,30,31,32,33,34,35,36].