To investigate the changes of serum GP73 before and after entecavir (ETV) antiviral treatment in patients with chronic hepatitis B virus infection, and to explore the influence of serum GP73 level on diseases progression and prognosis in CHB.

A total of 1 150 patients with chronic hepatitisB virus (HBV) infection admitted to The 180th Hospital of PLA during January 2012 to October 2014 were selected, including 100 cases with HBV carriers (HBV-C), 550 cases with CHB, 250 cases with HBV related primary hepatocellular carcinoma (HCC) and 250 cases with hepatitis B liver cirrhosis (LC). While 50 healthy controls were collected during the same period. The serum GP73 concentrations were detected by ELISA. The 30 cases of CHB liver tissue samples who took liver biopsy performed on the basis of informed consent were stained by immunohistochemistry, and the correlation of serum GP73 concentration and GP73 expression of liver tissues were discussed, respectively. The 200 patients among the 500 cases with CHB received ETV antiviral treatment for over one year, the condition changes were monitored, and the serum of GP73 were detected before and after 1 month, 3 months, 6 months, 9 months and 12 months treatment, respectively.

The serum levels of GP73 were significantly higher in patients with chronic HBV infections than those in healthy controls (F = 191.60, P = 0.000). With the development of chronic HBV infections, the serum GP73 showed a continuous increase among patients with HBV-C [(47.21 ± 17.69) ng/ml], CHB [(101.56 ± 67.18) ng/ml], HCC [(195.01 ± 104.22) ng/ml] and LC [(225.71 ± 99.37) ng/ml], and there were significant differences in all the groups (q_{HBV-C vs CHB} = 7.82, P = 0.000; q_{CHB vs HCC} = 15.85, P = 0.000; q_{HCC vs LC} = 2.63, P = 0.009). The serum GP73 concentration was positively correlated with the severity in patients with chronic HBV infections (r = 0.576, P = 0.000). The expression of GP73 protein in liver tissues of 30 CHB patients were weakly positive (6 cases, 20.00%), moderately positive (16 cases, 53.33%) and strongly positive (8 cases, 26.67%). With the increase of GP73 expression in liver tissues, the serum GP73 concentrations were synchronous elevated (F = 7.285, P = 0.003). The serum GP73 concentration was positively correlated with the expression of GP73 in liver tissues (r = 0.592, P = 0.001). After ETV antiviral treatment, with the recovery of the diseases, the serum GP73 concentration decreased significantly after the treatment for 1 month [(97.26 ± 42.52) ng/ml], 3 months [(68.21 ± 33.65) ng/ml], 6 months [(58.57 ± 29.52) ng/ml], 9 months [(51.76 ± 25.39) ng/ml] and 12 months [(53.37 ± 21.62) ng/ml], and there were significant differences compared with the levels of serum GP73 before [(113.09 ± 48.91) ng/ml] and after the treatment (t_{after 1 month vs. before} = 3.45, P = 0.001; t_{after 3 mo vs before} = 10.69, P = 0.000; t_{after 6 month vs before} = 13.50, P = 0.000; t_{after 9 month vs. before} = 15.74, P = 0.000; t_{after 12 mo vs before} = 15.79, P = 0.000). The largest serum GP73 concentration decrease occurred after 3 months of treatment, coinciding with the alanine aminotransferase normalization.

Serum GP73 levels are correlated with diseases progression in patients with chronic HBV infection. In patients treated with ETV, GP73 serum levels were reduced in response to the mitigation of liver injury. Serum GP73 could be a prognostic marker for chronic liver diseases.