With the in-depth study of the mechanism of immune checkpoints, ICIs such as CTLA-4 and PD-1/PD-L1 have shown good antitumor activity in malignant tumors such as urothelial carcinoma, renal cell carcinoma, melanoma, non-small cell lung cancer, colorectal cancer, and Hodgkin lymphoma and have been widely used in clinical practice (29). Here, PDCD1 is linked to urothelial carcinoma.