Glypican-3, over-expressed in hepatocellular carcinoma, is a useful tumor marker.

Abstract

Background: Glypican-3 (GPC3) is a member of glypican family of glycosyl-phosphatidyinositol anchored cell surface heparan sulfate proteoglycans. Previous studies have shown up-regulated GPC3 mRNA in hepatocellular carcinoma (HCC) using representational difference analysis or microarray analysis. Aims of this study were to analyze the GPC3 mRNA and protein expression, compared with corresponding non cancerous tissues in HCC and to determine the GPC3 in sera of HCC patients.

Materials and Methods: HCC and corresponding non-cancerous liver tissues were obtained from seven patients. The mRNA and protein expression were determined by real time RT PCR and western blot analysis. Primers for real time RT PCR were as follows: Forward; 5’-TgCTCTTACTgCCAgggACT-3’, Reverse; 5‘-gCTlTCCTgCAT-TCTTCTgg-3’. Serum GPC3 was determined by sandwich ELISA in 45 HCC and 18 control patients.

Results: In all seven HCC patients, GPC3 mRNA was found to be up-regulated in tumor compare with surrounding non-tumor. The GPC3 protein was over-expressed in HCC. Although 30 of 45 HCC patients were negative both for AFP and PIVKA-11, twelve of these were positive for serum GPC3. AFP and serum GPC3 were not correlated. Serum GPC3 was found to be present in patients with small HCC.

Conclusion: GPC3 was up-regulated in HCCs and was detectable in the serum of HCC patients. The combination of AFP and GPC3 may increase the sensitivity in diagnosing HCCs.