The co-expression of human leukocyte antigen DR (HLA-DR) and CD38 is related to the activation of CD8+ T cells, and the circulating activated CD8+ T cells (CD38+HLADR+) in patients with HBV-HCC are significantly higher than those in healthy controls, indicating that HBV-HCC patients have an effective adaptive immune response. This evidence concerns the gene CD8A and hepatocellular carcinoma.