CD8A and hepatocellular carcinoma: Specifically, the involvement of icaritin in advanced HCC treatment can relieve immunosuppression by reducing the generation of the inflammatory cytokines tumor necrosis factor-α (TNF-α) and IL-6, down-regulating the expression of the PD-L1 checkpoint in MDSCs and neutrophils, and restoring the function of interferon-γ (IFN-γ)+ CD8+ T cells [2, 47, 48].