癌胚抗原启动子驱动双自杀基因对裸鼠大肠癌移植瘤的作用  

Cytosine deaminase and thymidine kinase double suicide gene system driven by carcinoembryonic antigen promoter for the treatment of colorectal carcinoma xenograft in nude mice

作　　者：黄正接[1] 冯庆钊[1] 尤俊[1] 许林罗[1] 罗维远[1] 易文城[2] 曾岳岳[2] 罗琪[1] 

机构地区：[1]厦门大学附属第一医院厦门市肿瘤中心肿瘤外科,福建省厦门市361003 [2]福建医科大学第一临床医学院

出　　处：《中华医学杂志》2013年第28期2235-2240,共6页National Medical Journal of China

基　　金：福建省科技计划重点项目（201013026）;福建省医学创新课题（2012-CXB-29）

摘　　要：目的探讨癌胚抗原启动子（cp）驱动的双自杀基因系统Cp-CDglyTK对裸鼠大肠癌移植瘤的治疗作用。方法pcDNA3．1（-）Cp—CDglyTK质粒转染癌胚抗原阳性的SW480细胞和癌胚抗原阴性的HeLa细胞，反转录PCR检测目的基因的表达；给予不同浓度的前体药物5氟胞嘧啶（5-FC）及更昔洛韦（GCV）处理，用四甲基偶氮唑盐（MTr）法评估杀伤效应和旁观者效应。96只裸鼠在右侧腋窝皮下移植SW480细胞，72只移植HeLa细胞，建立大肠癌移植瘤模型。前体药物治疗实验中，取SW480和HeLa移植瘤裸鼠各48只，各分4组（I-Ⅳ，V～Ⅷ组，n=12），分别瘤体注射磷酸盐缓冲液（PBS）、GCV联合5-FC，腹腔注射PBS、GCV联合5-FC。自杀基因联合前体药物治疗实验中，余下48只SW480移植瘤裸鼠分为Ⅸ～Ⅻ组（n=12），24只HeLa移植瘤裸鼠分为ⅪIl～Ⅲ组（n=12），均经瘤体注射脂质体Lipofectamine@和质粒Cp—CDglyTK，再由腹腔注射药物（Ⅸ组：PBS，X组GCV，XI组：5-Fc，Ⅻ组：GCV联合5．FC，Ⅻ组：PBS，m组：GCV联合5-FC）。记录肿瘤体积、最终肿瘤重量和生存时间，比较分析各组裸鼠的治疗效果。结果转染质粒的SW480细胞有CDglyTK基因的表达，GCV联合5-FC对转染质粒的SW480细胞的抑制率（59．87％4-0．21％）明显高于HeLa细胞（9．90％±0．09％，P〈0．01），GCV与5-Fc联合用药对转染质粒的SW480细胞的生长抑制率和旁观者效应大于单一使用GCV或5-Fc（均P〈0．05）。II、IV、VI、Ⅷ组分别与对照组I、Ⅲ、V、Ⅶ组比较，肿瘤体积、最终瘤重和生存期差异均无统计学意义（均P〉0．05）。Ⅻ组最终肿瘤体积和最终瘤重均小于Ⅸ组、X组和Ⅺ组[（150．0±3．2）比（522．5±1．9）、（256．8±10．4）和（260．7±2．2）mm，（54．1±10．4）比（682．0±12．O）、（251．8±15．1）和（271．6±17．7）mg，均P〈0．05]；Ⅻ组的肿瘤生长抑制率和�Objective To explore the therapeutic efficacy of double suicide gene system driven by carcinoembryonic antigen （CEA） promoter （Cp-CDglyTK） on colorectal carcinoma xenograft in nude mice. Methods The plasmid pcDNA3.1 （ - ） Cp-CDglyTK was transfected into the CEA-positive SW480 and CEA-negative HeLa cells respectively. The expression of suicide gene was detected by RT-PCR. And the transfected cells were treated with 5-fluorocytosine （5-FC） and ganciclovir （GCV） at different concentrations and the cell-killing and bystander effects assayed by methyl thiazolyl tetrazolium （MTF）. Bya transplantation of cultivated cells, SW480 or HeLa cell lines were injected subcutaneously into right axillary of nude mice to establish 96 SW480 and 72 HeLa tumor animal models. Nude mice were completely randomized with statistical software according to tumor volume. For prodrug therapy, 48 SW480-bearing mice were divided equally into 4 groups of I - IV. At the same time, 48 HeLa-bearing mice were divided equally into 4 groups of V -Wl. Groups I ＆ Vreceived an intratumoral injection of PBS, groups Ⅱ ＆ VIGCV and 5-FC intratumorally, groupsⅢ ＆ WlI PBS intraperitoneally and groups IV ＆ VI GCV and 5-FC intraperitoneally. Forty-eight SW480-bearing mice were divided equally into 4 groups of IX - X and 24 Hela-bearing ones into groups of xm ＆ XIV in therapy experiment by suicide gene plus prodrug. Six groups received an intratumoral injection of liposome Lipofectamine and plasmid CP-CDglyTK and then an intraperitoneal injection of drug. The groups of IX and xm received an injection of PBS, group X GCV, group XI 5-FC and groups XlI ＆ GCV and 5-FC. The observation parameters included tumor bulk, tumor weight, survival time and treatment effect in each group. Results SW480 cells transfected by plasmid pcDNA3.1 （ - ） Cp- CDglyTK expressed CDglyTK gene. The inhibition rates of GCV and 5-FC were significantly higher than those of HeLa cells （ 59.87% ± 0.21% vs 9.90% ± 0.09% , P 〈 0.01 ）. And highe

关 键 词：肠肿瘤 癌胚抗原 基因 转基因 自杀 小鼠 裸 

分 类 号：R735.34[医药卫生—肿瘤]