CD274 and hepatocellular carcinoma: The inhibition of hepatoma-intrinsic cell cycle-related kinase (CCRK) in combination with the anti-PD-L1 antibody was resulted in a significant reduction in the percentages of tumor-infiltrating PMN-MDSCs and M-MDSCs, which were accompanied by markedly increased cytotoxic IFN-γ+TNF-α+CD8+ T cells, suggested that the co-blockage enhanced the efficacy of anti-PD-L1 in HCC via abrogation of MDSC (142).