Serum Golgi protein 73 as a tumor marker in diagnosis of primary hepatic cancer

Objective To investigate the feasibility of using serum Golgi protein 73(GP73) as a tumor biomarker in diagnosis of primary hepatic cancer(PHC).Methods Relative expression of GP73 mRNA was detected by SYBR Green qPCR in peripheral mononuclear cells from 103 PHC patients,13 cirrhosis patients,49 hepatitis patients,50 healthy persons,and in 8 normal liver tissue samples and 8 hepatic cancer tissue samples.Expression of GP73 in 7 liver tissue samples from patients with PHC diagnosed by pathology,1 normal liver tissue sample,and 1 cirrhosis liver tissue sample was analyzed by immunohistochemistry.Results No significant difference was found in expression of GP73 mRNA in peripheral mononuclear cells(F=3.013,P=0.055).However,the expression level of GP73 mRNA was significantly higher in hepatic cancer liver tissue samples than in normal liver tissue samples(12.64 vs 1.00,P0.05).Immunohistochemistry displayed that the GP73 in normal liver tissue samples was expressed in a small number of biliary canaliculi and liver parenchymal cells,while the GP73 in cirrhotic liver tissue samples was slightly expressed in cytoplasm of hepatocytes,which was concentrated in a granular shape near the biliary canaliculi with the biliary epithelial cells strongly stained.The GP73 in cytoplasm of hepatic cancer cells was also strongly stained and concentrated in a deep-brown granular shape near one side of epithelial cells in biliary canaliculi.The serum GP73 level was significantly higher in liver cancer patients than in healthy controls and hepatitis patients(χ2=62.541,P=0.000).The critical value of GP73 and AFP for the diagnosis of PAP was 113.2μg/L and 13.3μg/L,respectively,according to the ROC curves,with a sensitivity of 68.0% and 56.3% and a specificity of 94.8% and 91.8%,respectively.Conclusion High expression level of GP73 in serum of PHC patients may result from its synthesis in cytoplasm of hepatocytes and secretion into blood circulation.The positive serum GP73 rate is significantly higher than that of AFP in PHC patients,with a higher sensitivity and specificity than those of AFP as indicated by the ROC curves.