CD8A and hepatocellular carcinoma: Another study shows that insufficient radiofrequency ablation (RFA) can cause an immunosuppressive microenvironment by upregulating the expression of methyltransferase 1 and significantly increasing the accumulation of PMN-MDSCs or G-MDSCs and TGF-β2 expression to decrease CD8+ T cells, resulting in HCC recurrence and progression [18].