中文摘要：

目的：探讨凋亡抑制蛋白（IAP）家族成员Livin基因在骨肉瘤发生发展以及转移中的作用.方法：联合RNA干扰和质粒重组技术构建Livin基因短发夹RNA （shRNA）表达载体,筛选稳定沉默Livin表达的克隆.四甲基偶氮唑蓝法（MTT法）测定细胞增殖状况.划痕实验（Wound healing）和侵袭实验（Matrigel invasion assay）评价沉默Livin表达后细胞迁移和浸润能力的变化.免疫印迹法（Western blot）检测细胞周期蛋白Cyclin D1和基质金属蛋白酶-2,9（MMP-2,9）的蛋白表达变化.结果：shRNA稳定转染的骨肉瘤U2-OS细胞中Livin mRNA和蛋白水平明显下调.与对照组相比,细胞增殖,游走和侵袭能力明显下降,并且该克隆中Cyclin D1,MMP-2和MMP-9的蛋白表达也明显减弱.结论：凋亡抑制蛋白Livin能够在体外条件下促进骨肉瘤细胞增殖和侵袭作用,这一过程可能与Cyclin D1和MMP-2,9的表达增强有关.

英文摘要：

Objective：To investigate the roles of Livin,a member of the inhibitor of apoptosis protein （IAP） family during the tumorigenesis and metastasis of osteosareoma.Methods：After the construction of the vector expressing short hairpin RNA （shRNA） specific for Livin by means of RNA interference and plasmid recombination technology,selection of the stable transfectants for silencing Livin expression in U2-OS cells was performed.The proliferation of them was determined by using MTT method.The ability of cell migration and invasion was determined by Wound healing and invasion assay.The expression of Cyclin D1,MMP-2 and MMP-9 was detected by Western blot.Results：The mRNA and protein level of Livin in stable transfectants of U2-OS were identified.Compared with controlgroups,the knockdown of Livin significantly reduced cell proliferation,motility and invasion capacities of U2-OS cells.Moreover,the expression level of Cyclin D1,MMP-2 and MMP-9 decreased.Conclusion：Livin can promote cell proliferation and invasion in osteosarcoma cells in vitro,probably as a result of upregulation of Cyclin D1,MMP-2 and MMP-9.