As shown in Fig. 5C, the PD-L1 mRNA levels of the B16F10 cells were significantly down-regulated by the siPDL1@NPs and siPDL1@GalNPs in B16F10 cells compared with that by the siNC@NPs and siNC@GalNPs, indicating the successful RNAi of PD-L1 in cancer cells by the siPDL1 delivery nanocarriers. This evidence concerns the gene CD274 and cancer.