Abstract: Research in immunotherapy has achieved important progress in tumor treatments. Programmed cell death receptor 1 (PD-1) is mainly expressed on the T lymphocyte surface and serves as an important immune regulator. The interactions of PD-1 and its ligand, PD-L1, involve in tumor-induced immunosuppression. Some of the approved antibody drugs targeting PD-1/PD-L1 signaling showed significant clinical benefits.

Key words: tumor, immunotherapy, programmed cell death receptor 1, antibody drug