Soluble human leukocyte antigen-G expression in hepatitis B virus infection and hepatocellular carcinoma

Abstract

We investigated soluble human leukocyte antigen-G (sHLA-G) expression according to the phases of hepatitis B virus (HBV) infections and hepatocellular carcinoma (HCC). A total of 267 sera from anti-HBs positive healthy individuals (n=50), chronic HBV carriers (n=45), as well as patients with active hepatitis B (n=46), liver cirrhosis (LC, n=46) and early stage HCC (n=80) were collected and assayed for sHLA-G. Relationships between sHLA-G levels and clinicopathologic parameters including HCC stages, differentiation grades, and levels of aminotransferases, HBV DNA and alpha-fetoprotein (AFP) were assessed. Concentrations of sHLA-G were higher in the active hepatitis B and HCC groups (median sHLA-G 53.7 and 178.8 U/mL, respectively) in comparison to other groups (P<0.05), and there were no statistically significant differences among sHLA-G levels of the anti-HBs positive group, chronic HBV carrier and LC groups. Serum sHLA-G concentrations were not associated with clinicopathologic indices including the levels of aminotransferases, AFP, anti-HBs titer, HBV DNA, as well as HCC stages, numbers of tumor nodules, pathologic grades and presence of vessel invasion. The receiver operating characteristic area under the curve (AUC) value of sHLA-G for differentiating HCC from LC was 0.98, which was greater than that of AFP (0.78) (P<0.0001), and sensitivity and specificity of sHLA-G were, respectively, 90.0% and 95.7% for HCC when applying a cut-off level of 97.3 U/mL. Serum sHLA-G levels could be used as a diagnostic marker for HCC. Although sHLA-G levels did not reflect the severity of HBV infections and HCC, they were related with phases of the disease.