CD274 and cancer: For instance, two different liposomes were used for co-delivery of DOX and 5-carboxy-8-hydroxyquinoline (IOX1), in which IOX1 downregulated PD-L1 and inhibited P-glycoproteins (P-gp) of cancer cells, thus greatly upregulating effective concentration of DOX and enhancing DOX-induced ICD with reduced tumor immunosuppressive factors [21].