CD4 and hepatocellular carcinoma: When we further analyzed the co-expression of CMTM4/PD-L1 with CD4 or CD8, we found that high co-expression of CMTM4/PD-L1 with high CD4 expression was significantly related with better OS and progression-free survival (PFS) of HCC patients in a five-year survival period (Fig. 2E, P = 0.016; Supplementary Fig. 1E, P = 0.062), but high co-expression of CMTM4/PD-L1 with high CD8 expression did not show the significance (Fig. 2F, P = 0.50).