PARP1 and pancreatic neoplasm: Recently, study reported that PARP inhibitor pamiparib significantly up-regulated programmed death ligand-1 (PD-L1) expression in pancreatic cancer cells in vitro and in vivo, consequently, combination of PARPi and PD-1/PD-L1 immune checkpoint inhibitors generated greater therapeutic efficacy in pancreatic cancer patients [25].