What’s more, the expression of PD-L1 on the surface of peripheral CD4+CD25hiCD127low Tregs was significantly increased in patient with primary hepatocellular carcinoma, especially in patients with advanced disease, suggesting that the high PD-L1 expression on the surface of CD4+CD25hiCD127low Tregs may be related to tumor progression and patient prognosis [24]. This evidence concerns the gene CD4 and hepatocellular carcinoma.