靶向血管内皮生长因子的纳米颗粒制备及其对大肠癌细胞株SW620的作用  

Preparation of VEGF-targeting nano-gene carrier and its effects on colorectal cancer SW620 cell line

作　　者：朱役[1] 贾绍昌[2] 蔡凯[2] 项方[2] 

机构地区：[1]南京军区南京总医院疗养区,南京医学博士211131 [2]解放军第八一医院全军肿瘤中心肿瘤外科,南京210002

出　　处：《医学研究生学报》2011年第10期19-22,共4页Journal of Medical Postgraduates

基　　金：全军卫生医药科研基金(06MB146)

摘　　要：目的血管内皮生长因子(vascular endothelial growth factor,VEGF)在肿瘤新生血管形成过程中起关键性调控作用,是肿瘤靶向治疗的重要靶点之一。RNA干扰(RNA interference,RNAi)是RNA序列特异性转录后的基因沉默现象。小干扰RNA(small interfering RNA,siRNA)可介导同源mRNA降解。纳米颗粒黏附性强、体积小,可随血液循环进入细胞内,提高药物的生物利用度。在纳米颗粒表面整合精氨酸-甘氨酸-天冬氨酸(Arg-Gly-Asp,RGD)小肽配体可增加纳米颗粒与表达整合素的肿瘤细胞的特异性结合。聚乙二醇(polyethylene glycol,PEG)-聚乙烯亚胺(polyethyleneimine,PEI)是构建纳米颗粒的材料。文中利用RGD-PEG-PEI纳米材料构建载有靶向VEGF mRNA的siRNA质粒(psiRNA),并检测其转染大肠癌细胞株SW620的效率。方法制备由U6启动子驱动、可在哺乳动物细胞内稳定表达的VEGF靶向性质粒,与RGD修饰的PEG-PEI纳米载体结合后形成纳米复合物。测定所制备的纳米复合物的粒径、包封率和体外释放特性,并检测其对大肠癌细胞株SW620的作用。结果所制备的纳米复合物平均粒径为(142.3±21.6)nm,包封率为(83.5±5.8)%,大部分质粒在2周内释放,转染大肠癌细胞株SW620后72 h转染效率达最高,VEGF mRNA的抑制效率为78.4%。结论 RGD-PEG-PEI纳米基因载体转染效率较高,RGD-PEG-PEI/psiRNA可有效降低大肠癌细胞株SW620中VEGF mRNA的表达量,具有着良好的应用前景。Objective Vascular endothelial growth factor(VEGF),a target for targeting therapy,plays an important role in the forming of tumor angiogenic blood vessels.The aim of this study is to evaluate the transfection efficiency of RGD-modified PEG-PEI nanoparticle gene carrier(RGD-PEG-PEI) and its effect of VEGF RNAi in colorectal cancer cell line SW620.Methods We constructed shRNA plasmids targeting VEGF(psiRNA-VEGF) that can be expressed in mammalian cells directed by U6 promoter and formed nanocompounds of RGD-PEG-PEI and psiRNA-VEGF.The diameter,encapsulation efficiency,release rate in vitro of the nanocompounds and their effects in colorectal cancer cell line SW620 were measured.Results The average diameter of nanocompounds was(142.3±21.6)nm,the average encapsulation efficiency was(83.5±5.8)%,the plasmids were released in two weeks,the highest transfection efficiency of the nanocompounds appeared at 72h after transfection in colorectal cancer cell line SW620,and the inhibition efficiency of VEGF mRNA was 78.4%.Conclusion RGD-PEG-PEI nanoparticle gene carrier has higher transfection efficiency and RGD-PEG-PEI/psiRNA can effectively reduce the VEGF mRNA expression in colorectal cancer cell line SW620,which makes a good prospect.

关 键 词：血管内皮生长因子 精氨酸-甘氨酸-天冬氨酸小肽 聚乙二醇-聚乙烯亚胺 纳米 

分 类 号：R735[医药卫生—肿瘤]