目的：探讨靶向骨桥蛋白基因(osteopontin，OPN)的siRNA片段对U87胶质瘤细胞生长和侵袭力的影响及其可能的作用机制。方法:根据OPN基因序列设计并合成的siRNA片段（OPNRNAi）转染U87细胞。MTT法检测U87细胞增殖；Western blotting检测OPN及基质金属蛋白酶(matrix metalloprotease，MMP）2、MMP9蛋白的表达；Transwell小室侵袭实验检测U87细胞的侵袭力；明胶酶谱法检测MMP2、MMP9的酶活性。结果：体外合成的OPNRNAi能有效抑制U87细胞中OPN蛋白的表达（P<0.05），OPNRNAi同时还能下调MMP2、MMP9蛋白的表达（P<0.05）及其酶活性（P<0.01），并抑制U87细胞的增殖（P<0.05）和侵袭力（P<0.05）。结论：OPNRNAi能够有效抑制U87胶质瘤细胞的生长及其侵袭力，其机制与其抑制OPN下游基因MMP2、MMP9的表达和酶活性有关。

Objective:To study the effect of siRNA targeting osteopontin（OPNRNAi）on the proliferation and invasiveness of U87 glioma cells and the possible mechanism. Methods: OPNRNAi was synthesized according to the gene sequence of OPN protein and was transfected into U87 cells. The proliferation of U87 cells was examined by MTT; matrix metalloprotease (MMP) 2 and MMP9 expression were detected by Western blotting assay; transwell assay and gelatinzymogram were used to detect the invasion ability of U87 cells and gelatinase acitivity of MMP2 and MMP9, respectively.Results:Synthesized OPNRNAi effectively inhibited the expression of OPN in U87 cells (P<0.05). OPNRNAi also significantly decreased the expression of MMP2 and MMP9 in U87 cells (P<0.05) and the gelation activity of MMP2 and MMP9 (P<0.01), and inhibited the proliferation and invasivenss of U87 cells（all P<0.05）. Conclusion: Knockdown of OPN with OPNRNAi can inhibit the proliferation and invasiveness of U87 cells, which is probably related to the decreased expression of MMP2 and MMP9 genes and their gelatinase acitivities.

国家自然科学基金资助项目（No. 30672165）；江苏省医学重点人才项目（No.RC2007061）