CD4 and hepatocellular carcinoma: In consistent with these studies, our immune cell infiltration results also showed that CMTM4 expression had a positive relationship with CD4 and CD8 T cell infiltration levels, and co-expression of CMTM4/PD-L1 combined with CD4 T cell infiltration posed a positive effect on HCC prognosis, suggesting CMTM4 as a trigger combined with PD-L1 could improve tumor microenvironment of HCC by targeting T lymphocyte infiltration.