Objective： To investigate the expression of Glypican-3 gene in （α-fetoprotein （AFP）-negative hepatocellular carcinoma （HCC） and clarify whether Glypican-3 expression is a useful parameter for the diagnosis of hepatocelhllar carcinoma （HCC）, especially for AFP-negative ones. Methods： Forty-one specimens of AFP-negative hepatocellular carcinoma and para-carcimoma tissue were studied for the expression of Glypican-3 by Northern blot. The expression of Glypican-3 protein was detected immunohistochemically with specific polyclonal antibody. Results： Northern blot analysis indicated that the expression of Glypican-3 mRNA was intensively detected in 30 of 41 AFP-negative HCC （73.17%）. In contrast, Glypican-3 mRNA was only weakly detected in 4 of the surrounding non-tumor liver tissues. There was significant difference in the Glypican-3 mRNA expression in large tumors （〉5 cm） （79.31%） and in small tumors （〈5 cm） （41.67%） （P〈0.01）. Gypican-3 mRNA was more frequently overexpressed in poorly differentiated HCC than in well differentiated ones （76.47% vs. 42.86%, P〈0.05）. The Glypican-3 expression was not correlated with age. sex. ttbsAg seropositivity, fibroeapsule, portal venous embolus and intrahepatic metastasis. The overexpression of Glypican-3 protein in HCC was targeted in tumor cells, not in bile duct cells and other interstitial cells. Conclusion： Glypican-3 was specially overexpressed in AFP-negative HCC, and its expression was closely correlated with the tumor size and tumor grade. Glypican-3 gene may play important roles in hepatocareinogenesis, and can be used as a new biochemical marker of HCC, especially for AFP-negative HCC.
