中文摘要：

目的：骨桥蛋白（Osteopontin，OPN）在肝癌细胞侵袭中的作用机制。方法：采用siRNA干涉的方法处理人肝癌细胞，用PCR和Western-blot法检测OPN的表达；用transwell小室检测不同处理后的HepG2和MHCC97H细胞的侵袭能力；采用Western．b1．ot和ELISA方法检测基质金属蛋白酶-2（matrixmetalloproteinase-2，MMP-2）和血管内皮生长因子（vascularendothelialgrowthfactor，VEGF）蛋白表达和活力的变化情况。结果：在不同肝癌细胞系中，随着肝癌细胞系侵袭能力的增强，OPN的表达逐渐增高。siRNA可以降低HepG2和MHCC97H细胞中OPN的表达，并且能够降低HepG2和MHCC97H细胞的侵袭能力；抑制OPN的表达能够降低MMP-2和VEGF蛋白表达和蛋白活性。结论：OPN在肝癌侵袭过程中起着重要作用，其作用机制可能是通过调控MMP-2和VEGF蛋白表达和活性来参与肝癌的侵袭，OPN可作为肝癌侵袭转移治疗的新靶点。

英文摘要：

Objective： To investigate the mechanis by which OPN regulates the invasion ofhepatocellular carcinoma cells. Methods： Hepatocellular carcinoma cells were transfected with siRNA against OPN （siRNA-OPN）, and the OPN expression at the mRNA and pro- tein levels were detected by RT-PCR and Western-blot respectively. Invasion ability of HepG2 and MHCC97H transfected with siRNA- OPN or control siRNA was measured by transwell. Western-blot and ELISA were used to detect protein expression and activity of MMP-2 and VEGF. Results： The mRNA and protein expression levels of OPN were positively correlated with the invasion abilities of different hepatocellular carcinoma cell lines, siRNA-OPN could effectively reduce the expression of OPN in HepG2 and MHCC97H, and lead to the reduction of the invasion ability of HepG2 and MHCC97H and the protein expression and activity of MMP-2 and VEGF. Conclusion： OPN plays an important role in the invasion of hepatocellular carcinoma, of which the mechanism may be that OPN regulates the expression and activity of MMP-2 and VEGF. OPN can be used as a new target to treat hepatocellular carcinoma.