CD274 and melanoma: Of these 21 publications, 15 examined the efficacy of immune checkpoint inhibitors and their clinical studies, mainly exploring the effectiveness of different inhibitors (mainly PD-1 and PD-L1 blockers) in a variety of cancers, such as non-small-cell lung cancer, melanoma, etc., and comparing the efficacy and safety of different PD-1 monoclonal antibodies, as well as the effect of combination therapy.