CD4 and hepatocellular carcinoma: One study found that CD4+ and CD8+ T lymphocytes expressing CCR6 were significantly reduced in the peripheral blood of HCC patients, while CCR6 was highly expressed in tumor‐infiltrating lymphocytes and adjacent non‐tumor‐infiltrating lymphocytes of the liver, suggesting that CCR6 plays an important role in the recruitment of lymphocytes from peripheral blood to HCC [35].