A previous study by Cai et al. has found that TK1 expression is significantly associated with infiltrating levels of “CD4 memory resting T cells”, “CD4 memory activated T cells”, “follicular helper T cells”, Tregs, “naïve B cells”, and “activated dendritic cells” in hepatocellular carcinoma [8]. This evidence concerns the gene CD4 and hepatocellular carcinoma.