中文摘要：

目的：检测LEF-1在骨肉瘤细胞株F4和F5M2中的表达;探讨siRNA干扰前后对骨肉瘤细胞中LEF-1的表达及对细胞侵袭和迁移的影响。方法：采用Western-blot及qRT-PCR检测具有不同转移能力的骨肉瘤细胞株（F4,F5M2）中LEF-1的表达水平;利用RNAi干扰技术将LEF-1 siRNA转染到F5M2细胞中,使用Western-blot检测转染LEF-1 siRNA后细胞中LEF-1蛋白的表达变化;Tanswell实验检测干扰LEF-1的表达对F5M2细胞侵袭和迁移的影响。结果：LEF-1在骨肉瘤细胞株F4,F5M2中差异表达,其中在F5M2细胞中的表达较高。在转染LEF-1 siRNA的F5M2细胞中,LEF-1蛋白表达水平显著降低。Tan-swell实验结果显示,与阴性对照组和空白对照组相比,实验组F5M2细胞的侵袭和迁移能力显著降低。结论：LEF-1 siRNA可以下调骨肉瘤细胞中LEF-1的表达,抑制骨肉瘤细胞的侵袭和转移。LEF-1有可能成为骨肉瘤诊治的新靶点。

英文摘要：

Objective：To detect the expression of LEF - 1 in the human osteosarcoma cell line F4 and FSM2, and investigate the influence of siRNA interfering the expression of LEF - 1 and the invasion and migration in human os- teosarcoma cell . Methods：The expression of LEF - 1 protein and mRNA was detected by using Western - blot and quantitative Real Time PCR respectively. FSM2 cells were tansfected with LEF - 1 siRNA and LEF - 1 protein levels were detected using Western - blot. Influence of siRNA interfering the expression of LEF - 1 on the invasion and mi- gration of human osteosareoma cell line F5M2 was detected using Tanswell. Results ：The results of Western - blot and quantitative Real Time PCR showed that LEF - 1 was expressed differently in the human osteosarcoma cell line F4 and FSM2. FSM2 cells had the higher level. The protein levels of LEF - 1 decreased after transfected with LEF - 1 siRNA. Compared with the negative control and the blank control, LEF - 1 siRNA - transfected cells showed a de- crease on the invasion and migration. Conclusion： LEF - 1 siRNA inhibited the expression of LEF - 1, the invasion and migration of osteosarcoma cell.