PDCD1 and urinary bladder cancer: The immune checkpoints such as cytotoxic T-lymphocyte antigen-4 (CTLA-4), programmed cell death 1 (PD-1) and programmed death ligand-1 (PD-L1) were the most promising targets, meanwhile their immunosuppressants have been clinically demonstrated effective in NSCLC, melanoma and bladder cancer et al. [7–12].