Abnormal Expression of Golgi Protein 73 in Clinical Values and Their Role in HBV-Related Hepatocellular Carcinoma Diagnosis and Prognosis

BACKGROUND: The up-regulation of hepatic Golgi protein 73 (GP73) is associated with the progression of hepatocellular carcinoma (HCC). However, the exact mechanism and clinical values of its diagnosis and prognosis still need to be clarified. OBJECTIVES: To investigate the clinical values of abnormal liver or circulating GP73 expression and their effect on HCC diagnosis and prognosis. MATERIALS AND METHODS: The expression of GP73 was investigated in 88 cancerous and self-control non-cancerous tissues using tissue microarrays with immunohisto- chemistry and was confirmed by Western blotting. Circulating GP73 levels were detected in the sera of 281 patients with liver diseases using enzyme-linked immunosorbent assay. RESULTS: The levels of circulating GP73 expression in the HCC group were higher than those in any group of benign liver diseases or controls. No significant difference was found between GP73 expression and patients’ sex or age, tumor size, or AFP level except for those with hepatitis B virus (HBV) infection or distal metastasis (P < 0.05). The area under the receiver operating characteristic curve, sensitivity, and specificity for HCC diagnosis were 0.881, 78.34%, and 77.59% for GP73 levels over 70 μg/L or 0.754, 71.97%, and 84.48% for alpha-fetoprotein levels over 50 μg/L, respectively. The total incidence of GP73 plus alpha-fetoprotein was up to 87.26% for HCC. A positive GP73 result with brown particles was mainly located in the cytosol, with a few in the nucleus and none in the cell membrane, with abnormal expression in HCC tissues (480.7 ± 148.7) that was significantly higher (t = 10.730, P < 0.001) than those in their non-cancerous tissues (208.0 ± 66.1). The high GP73 expression in HCC was related to lymph node metastasis (χ(2) = 6.940, P = 0.008), gross classification (χ(2) = 6.311, P = 0.012), HBV (χ(2) = 4.803, P = 0.028), tumor node metastasis staging (χ(2) = 4.887, P = 0.027), and five-year survival (χ(2) = 5.206, P = 0.023). CONCLUSIONS: Abnormality of hepatic or circulating GP73 expression should be regarded as an emerging biomarker for HCC diagnosis and prognosis.