利用siRNA抑制HER2表达探究.docVIP

利用siRNA抑制HER2表达探究 　 【关键词】 siRNA 毕业论文 　　 The Inhibition of HER2 Expression by siRNA 　　Abstract：Objective To inhibit the expression of HER2 gene in MCF7 human breast carcinoma cells by siRNA. Methods Five siRNAs targeting HER2 were designed, and thEir corresponding expression vectors were constructed and transformed into MCF7 cells. After selection, the stable transfected cells were obtained. The HER2 mRNA abundance in the stable transfected cells was analyzed by RTPCR. The HER2 protEIn expression in these cells was analyzed by flow cytometry (FCM). The stable transfected cells were transplanted in nude mice, and the HER2 protein expression in transplant tumor was detected with immunohistochemical method. Results siRNA 3P could effectively decrease the HER2 mRNA expression in MCF7 cells. The FCM data showed that the HER2 protein expression in siRNA 2P and 3P transfected MCF7 cells decreased. All the five siRNAs targeting HER2 could decrease the tumorigenesis of MCF7 cells in nude mice. Correspondingly, the HER2 protein expression in transplant tumors was also reduced. Conclusion The siRNAs targeting HER2 mRNA could effectively inhibit HER2 expression in vivo and in vitro, and will be useful for gene therapy of breast cancer. 毕业论文 　　Key words：HER2; Small interfering RNA (siRNA); Breast cancer 　　摘要：目的 利用siRNA抑制人乳腺癌MCF7细胞中HER2基因的表达。 方法 针对HER2 mRNA设计了5条siRNA，并构建相应的表达质粒，将质粒转染MCF7乳腺癌细胞，筛选稳定表达株，利用RTPCR 分析 siRNA对细胞中HER2 mRNA的降解作用；利用流式细胞术分析细胞表面HER2蛋白的表达；利用裸鼠进行体内成瘤性实验，用免疫组化法检测瘤组织中HER2的表达。结果 siRNA 3P能明显降低MCF7细胞中HER2 mRNA的丰度；流式细胞分析表明，其中siRNA 2P 和3P稳定转染的MCF7细胞表面HER2的表达明显降低；五种表达不同siRNA的MCF7细胞在裸鼠体内的成瘤性均有所降低，并且瘤组织中HER2蛋白的表达也明显减少。结论 靶向HER2 mRNA 的siRNA能在体内外有效抑制HER2的表达，可用于乳腺癌的基因 治疗 。 毕业论文 　　关键词：HER2；小干涉RNA（siRNA）；乳腺癌 论文代写 　　0 引言 　　HER2在乳腺癌、卵巢癌、前列腺癌、胃癌、肺癌等多种恶性肿瘤中存在基因扩增或过度表达，而在正常人体腔上皮、腺上皮及胚胎中表达水平很低[1]。约30%的乳腺癌患者伴随HER2的过表达[2]，HER2过表达与乳腺癌的发生、 发展 、转移和不良预后密切相关。 　　RNA干涉（RNA interference, RNAi）是近年发展起来的一种快速、高效、易于操作的使特异靶基因失活的技术。本实验利用RNA