重组腺病毒驱动KDR-CDglyTK融合基因系统对MCF-7细胞及血管内皮细胞的靶向杀伤作用  

Adenovirus-mediated CDglyTK fusion gene system driven by KDR promoter selectively kills MCF-7 breast cancer cells and vascular endothelial cells

作　　者：苏国强[1] 黄宗海[1] 刘志锋[2] 郭爱华[2] 俞金龙[1] 厉周[1] 宋彗娟[1] 

机构地区：[1]南方医科大学珠江医院,广东广州510282 [2]南方医科大学病理生理教研室,广东广州510515

出　　处：《第一军医大学学报》2004年第12期1346-1349,1358,共5页Journal of First Military Medical University

基　　金：国家863计划项目(2001AA217171);广东省自然科学基金项目(013072)~~

摘　　要：目的探讨腺病毒介导血管内皮生长因子受体(KDR)启动子驱动的CDglyTK融合基因体系对人乳腺癌细胞株MCF-7及血管内皮细胞(ECV304)选择性杀伤作用。方法将质粒pAdEasy-KDR-CDglyTK在293细胞内包装、扩增后,体外感染表达KDR的MCF-7、ECV304细胞株和对照组不表达KDR的LS174T细胞株,并给予不同浓度的前药5-FC和/或GCV,观察该体系对不同细胞株的杀伤效应及其旁观者效应。并通过流式细胞仪检测前药对瘤细胞周期的影响。结果所得病毒滴度为2.0×1012pfu/ml。3种细胞的感染率相似,其感染率随腺病毒滴度的递增而增加,当感染复数(MOI)为200时,所有细胞株均达约100%感染。以MOI为100的重组体分别感染各细胞株表现出对前药的不同敏感性:表达KDR的MCF-7细胞和ECV304细胞对前药具有较高的敏感性,二者敏感性差异无显著性意义(P=1.00);与前2者相比,不表达KDR的LS174T细胞对前药不敏感(P<0.001)。CDglyTK融合基因的疗效优于任一单自杀基因(P<0.001)。将感染腺病毒的细胞与未感染细胞以不同混合培养,观察到该体系明显的旁观者效应。流式细胞术检测表明该体系抑制MCF-7细胞DNA的合成,表现为G1期细胞比率增多及S期细胞减少(P<0.001)。结论KDR基因启动子调控的CDglyTK融合基因体系可选择性杀伤乳腺癌MCF-7细胞及血管内皮细胞。Objective To observe the selective killing of MCF-7 human breast cancer cells and vascular endothelial ECV304 cells by adenovirus (Ad)-mediated double suicide gene driven by KDR promoter. Methods The plasmid pAdEasy-KDR- CDglyTK was transfected into 293 packaging cells for amplification of the infectious Ad, which were then used to infect KDR-producing ECV304 and MCF-7 cells and LS174T cells that did not produce KDR. The infected cells were treated with 5-FC and/or GCV at different doses to observe the cell-killing and bystander effects of AdKDR-CdglyTK. The cell cycle changes were also detected by flow cytometry. Results The Ad at the titer of 2.0×1012pfu/ml was obtained after the amplification, whose infection rates of the cells were similar, but could be increased gradually with the multiplicity of infection (MOI) till reaching 100% with the MOI of 200. The infected cells exhibited different sensitivities to the two prodrugs: ECV304 cells and MCF-7 cells infected with Ad-KDR-CDglyTK showed similar high sensitivity to the prodrugs (P=1.00), whereas the infected LS174T cells appeared to be less sensitive (P<0.001). The killing effect of CD/TK fusion gene on the target cells was much stranger than that of either suicide gene (P<0.001), but all exhbiting considerable bystander effect. In addition, the cell cycle of MCF-7 cells was arrested at G1 phase. Conclusions CD/TK fusion gene system driven by KDR promoter can selectively kill KDR-expressing vascular endothelial cells and MCF-7 cells.

关 键 词：乳腺肿瘤 血管内皮 血管内皮生长因子受体启动子 基因治疗 腺病毒 

分 类 号：R737.9[医药卫生—肿瘤]