中文摘要：

短发夹RNA（short hairpin RNA,shRNA）因稳定性好、可实现目标蛋白的长期沉默成为基因治疗的有力手段,而聚乙烯亚胺（PEI）递送基因常会引发细胞毒性。本课题组为屏蔽PEI正电荷,采用透明质酸（HA）包裹PEI/shRNA制备“三明治”式自组装纳米复合物HA/PEI/shRNA用于抗肿瘤靶向治疗。自组装得到的纳米复合物粒径约150 nm,ζ电位约-30 mV。凝胶电泳试验表明在一定范围内,HA的加入并不影响shRNA络合。细胞摄取试验表明,该复合物能通过MDA-MB-231细胞表面HA受体介导的细胞内吞而被摄取。MTT试验表明HA/PEI复合物的细胞毒性远低于PEI,HA/PEI/shRNA纳米复合物递送治疗型基因细胞毒性较大、转染效率高。综上所述,自组装纳米复合物HA/PEI/shRNA是一种有潜在价值的基因靶向传输系统。

英文摘要：

Short hairpin RNA （shRNA） has been a powerful treatment of gene therapy due to its favorable stability and efficacy of permanently silencing target protein. Polyethylenimine （PEI） would cause cytotoxic used as a vehicle to deliver genes. In this study, cationic nanocomplexes PEI/shRNA were shielded by anionic polymers hyaluronic acid （HA） to prepare ＂sandwich＂ nanocomplexes HA/PEI/shRNA to safely and targetedly deliver genes into cancer cells. The particle size and ζ potential of the self-assembled nanocomplexes were about 150 nm and -30 mV. The gel electrophoresis assay indicated that anionic polymer addition did not affect shRNA compression within a certain rang. Confocal laser scanning microscopy （CLSM） confirmed that the ternary nanocomplexes were uptake by MDA-MB-231 cells via HA receptor-mediated endocytosis. MTT assay showed that compared to PEI, HA/PEI nanocomplexes owned much lower cytotoxicity, and HA/PE1/shRNA nanocomplexes with therapeutic gene owned significant cytotoxicity. Furthermore, HA/PEI/shRNA nanocomplexes possessed high transfection efficiency and significantly inhibited the expression of KIAA 1199. Collectively, the ternary nanocomplex HA/PEI/shRNA could be a promising and novel targeting delivery system to treat metastatic cancer cases.