A Study of Diagnostic Value of Golgi Protein GP73 and its Genetic Assay in Primary Hepatic Carcinoma

Abstract

This study aimed to investigate the diagnostic values of GP73 protein in patients' serum with primary hepatic carcinoma (PHC). Also GP73 mRNA expression level in peripheral blood mononuclear cells (PBMCs) and liver tissue between health controls and PHC patients was interrogated. Finally the role of combined detection of serum GP73 and alpha-fetoprotein (AFP) in high-risk population screening was evaluate, in an attempt to justify the new, sensitive, specific and rapid measure for the diagnosis and detection of PHC. Serum proteins of GP73 and AFP were examined in 73 patients with PHC, 13 patients with hepatic cirrhosis, 32 patients with hepatitis and 62 healthy subjects using enzyme-linked immunosorbent assay (ELISA). The relative expression levels of GP73 mRNA in PBMCs and liver tissues were examined by using SYBR Green quantitative reverse transcription polymerase chain reaction (RT-PCR) assay, calculated with the comparison of Cq value. In contrast to patients with cirrhosis and hepatitis, or healthy subjects, PHC patients had their serum GP73 and AFP significantly elevated (P < 0.05) while their PBMCs GP73 mRNA was not significantly different from those with cirrhosis and hepatitis, or healthy subjects (P > 0.05). The expression level of GP73 mRNA was significantly higher in PHC liver tissue than in normal liver tissue. The sensitivity for serum GP73 and AFP in PHC was 68.5% and 28.8%, respectively while that for the combined detection was up to 74%, justifying that the combined detection could prevent the false negative diagnosis by AFP alone and significantly improve the detection rate. As a new diagnostic biomarker of PHC, GP73 protein in serum was highly sensitive and specific. GP73 mRNA in PHC liver tissue specimens instead of whole blood could be used for the diagnosis of PHC as a tumor biomarker, whose detection was highly invasive, risky and afflicting otherwise. The combined detection of GP73 and AFP in serum effectively improved the diagnosis of PHC, in addition to the screening in high-risk population.