CD274 and cancer: To improve the response rate to ICIs, numerous combination strategies have been studied in preclinical and clinical trials, including combining PD-L1/PD-1 inhibitors with chemotherapeutics such as cyclophosphamide, radiotherapy, targeted therapy, agonistic costimulatory antibodies targeting CD134, CD137 or ICOS, innate immune stimulators such as STING agonists, epigenetic modulators, and cancer vaccines such as oncolytic viruses (19, 22, 23).