CD274 and cancer: Recently, it is reported that inhibiting sEV PD-L1 secretion could improve the efficacy of anti-PD-L1 and anti-cancer immunity because tumor-derived sEV and sEV PD-L1 contribute to tumor growth and immune evasion by inhibiting T cell activity, such as NF-κB, IL-2, and IFN-γ activation [38,39].