IDO1 and urinary bladder cancer: In order to investigate the correlation between immunotherapy and bladder cancer, 14 immune checkpoint inhibitors inlcuding BTLA, GITR, TNFRSF14, IDO, LAG-3, PD-1, PD-L1, PD-L2, CD28, CD40, CD80, CD137, CD27, and Ctla-4 were selected for analysis.