The Expression And Significance Of Glypican-3 Gene In Hepatocellular Carcinoma And Its Affect In Hepatocarcinogenesis

BACKGROUND AND OBJECTIVE:Hepatocellular carcinoma(HCC) is a common malignant tumor in the world,its development is latent and rapid. The five year-survival rate of HCC is very lower,and about the 67%patients have been in the later stage when he first saw a doctor.So that early detection of HCC is critical for its successful treatment.Alphafetoprotein(AFP)level in serum is a sensitive marker for HCC.However,30-40%of HCC patients were negative for AFP.Therefore,looking for a new and specific tumor marker that expresses in HCC patients with negative AFP will improve the diagnositic level in early stage of HCC,and improve the curative effect.Some research prove that glypican-3(GPC-3)gene may be a new sensitive tumor marker and target in gene therapy of HCC,A group of serum and tissue sample of HCC were detected in present study to explore the relationship between the expression GPC-3 and clinical parameter,and the expression GPC-3 and Insulin like growth factor-Ⅱ(IGF-Ⅱ)expression at mRNA and protein levels were tested on the samples from HCC and the para-carcinoma tissues to reveal the mechanism of action in HCC.METHODS:The Enzyme-linked immunosorbent assay(ELISA)was employed to test the expression of GPC-3 in 60 the serum from cases of HCC,in 13 cases of hepatitis or hepatic cirrhosis,and 14 cases of normal contral. Reverse transcription polymerase chain reactions(RT-PCR)was employed to determine the expression of GPC-3 and IGF-Ⅱin 70 cases of HCC tissues and their para-carcinom tissues,and 18 cases of normal liver tissues.The relationship between the expression of GPC-3 and IGF-Ⅱand the clinical parameters,such as AFP,the number of tumor,the diameter of tumor,the clinical stage,the recurrence of tumor,extrahepatic metastasis,the portal vein and tumor thrombus,the differentiation of tumor.Immunohistochemical staining were also employed to determine the expression of glypican-3 and IGF-Ⅱin 80 cases of HCC tissues and their para-carcinom tissues,and 8 cases of normal liver tissues.The relationship between the expression of GPC-3 and IGF-Ⅱand the clinical parameters,such as AFP,the number of tumor,the diameter of tumor, the the clinical stage,the recurrence of tumor,extrahepatic metastasis,the portal vein and tumor thrombus,the differentiation of tumor.RESULTS.Serum GPC-3 cut off level was set as more than or equal to 60 pg/ml.Positive rates of GPC-3 were 66.67%,15.38%and 0 in HCC serum,in hepatitis or hepatic cirrhosis serum and in normal control respectively.The positive rates of GPC-3 in HCC serum was significantly higher than that normal control and hepatitis or hepatic cirrhosis(p＜0.05).The expression of GPC-3 in the HCC serum were significantly correlated with the clinical parameters,such as the clinical stage,the presence of extrahepatic metastasis,the recurrence of tumor,the level of AFP,but not correlated with the portal vein tumor thrombus, the tumor size,the number of tumor,HBsAg and differentiation of tumor cells. Positive rates of GPC-3 and AFP in the 60 cases of HCC serum were not difference,but the positive rates(83.33%)detected by both of GPC-3 and IGF-Ⅱwere significantly higher that of detected by GPC-3 or IGF-Ⅱalone (66.67%).The result from RT-PCR show that the positive rates of GPC-3 mRNA and IGF-ⅡmRNA in the HCC tissues were higher than those in the para-carcinom tissues(82.85%and 92.86%vs 34.28%and 81.43%respectively, P＜0.05).The expressions of GPC-3 mRNA and IGF-ⅡmRNA in the HCC tissues were significantly higher than those in the para-carcinom tissues (0.596±0.205 and 0.750±0.309 vs 0.428±0.137 and 0.648±0.237 respectively). There was no expression GPC-3 in the 18 cases of normal liver tissues. Immunohistochemical:Positive rates of GPC-3 and IGF-Ⅱin the HCC tissues were higher than those in the para-carcinom tissues expecting(73.75%and 76.25%vs 53.75%and 48.75%respectively,P＜0.05).The expression of GPC-3 was positively correlated with expressions of IGF-Ⅱin HCC tissues. The expression of GPC-3 and IGF-Ⅱin the HCC tissue was significantly correlated with the clinical parameters,such as differentiation of tumor,the presence of extrahepatic metastasis and the tumor size but not correlated with the portal vein tumor thrombus,the number of tumor,the recurrence of tumor, the level of AFP in serum,and the the clinical stage.CONCLUSION:1.Present research found that the expression level of GPC-3 was high in HCC serum.It may be a tumorous marker in serum and may improve the positive rate in HCC diagnosis when set together AFP.2.The expression of GPC-3 in the HCC serum was significantly correlated with clinical parameters,such as clinical stage,presence of extrahepatic metastasis, recurrence of tumor,level of AFP in serum.GPC-3 and IGF-Ⅱmay play the important roles in development and metastasis of HCC.