Besides, these ablative modalities can also stimulate an antitumor immune response by locally releasing tumor antigens, however, tumoricidal effects are usually suppressed by the immunosuppressive tumor microenvironment of HCC (immunosuppressive mechanisms involving impaired tumor-associated antigen-processing and presentation, lack of CD4+ T-cell responses, enhanced myeloid-derived suppressor cells, enhanced regulatory T cells, and increased expression of programmed cell death ligand-1 21). This evidence concerns the gene CD4 and hepatocellular carcinoma.