VP22增强慢病毒介导的自杀基因治疗抑制人卵巢癌裸鼠腹腔种植瘤生长的研究

目的:探讨单纯疱疹病毒壳膜蛋白VP22的细胞间传递作用促进HSV-TK/GCV(单纯疱疹病毒胸苷激酶/更昔洛韦)系统对卵巢癌腹腔移植瘤的杀伤效应。方法:将慢病毒包装质粒、包膜质粒、转移载体质粒采用磷酸钙沉淀法共转染包装细胞293T,收集病毒上清,并建立人上皮性卵巢癌(3AO)细胞株腹腔移植瘤模型。单药组分为TK+生理盐水(NS)组、VP22-TK+NS组、NS+NS组,分别腹腔注射慢病毒TK、VP22-TK或NS1ml,继而腹腔注射NS;联合用药组分为TK+GCV组、VP22-TK+GCV组、NS+GCV组分别腹腔注射慢病毒TK、VP22-TK及NS,24h后腹腔注射GCV治疗。每组裸小鼠均为5只。观察各组裸鼠的生存时间及慢病毒的毒性作用。结果:平均生存时间TK+NS组、VP2-TK+NS组、NS+NS组、NS+GCV组、TK+GCV组、VP2-TK+GCV组分别为18.3±2.7d、18.4±1.9d,17.2±1.3d、18.7±1.9d、21±4d和46±22d,6组差异有显著性(χ2=24.81,P=0.002);并且VP2-TK+GCV组平均生存时间较TK+GCV组裸鼠明显延长(χ2=7.42,P=0.006)。结论:VP22介导的自杀基因产物的细胞间扩散作用可明显加强对体内肿瘤细胞的杀伤效应。

VP22 enhanced lentivirus mediated suicide gene therapy strategy for the treatment of ovarian cancer transplanted intraperitoneally in nude mice

Objective:To explore the enhanced cell-killing effect in vivo of HSV-TK/GCV gene therapeutic system using VP22 intercellular trafficking.Methods:Lentivirus encoding TK and VP2-TK were constructed.30 female BABL/c mice were injected intraperitoneally with human ovarian epithelial carcinoma cells line 3AO,and randomly divided into 6 groups:NS(normal saline)+NS group(injected intraperitoneally with NS once per day for 3 days and then with NS 24hour after once a day for 5 days),VP22-TK+NS group(injected with herpes simplex virus structural protein VP22-TK once a day for three days and then with NS 24hour after once a day for 5 days),VP22-TK+NS group(injected with VP22-TK and then NS in the same way),NS+ganciclovir(GCV) group(injected with NS and then with GCV),VP22-TK+GCV group(injected with VP22-TK and then GCV),and VP22-TK+GCV group(injected with VP22-TK and then GCV).The survival time was observed.Results:The mean survival times of the six experimental groups were 18.3±2.7day,18.4±1.9day,17.2±1.3day,18.7±1.9day,21.0±4.0day,and 46.0±22.0day respectively,there were significant differences among the above group(χ2=24.81,P=0.002).The survival time of animals treated with VP22-TK+GCV was significantly longer than that of animals treated with TK+GCV(χ2=7.41,P=0.006).Conclusion:VP22 enhances intercellular trafficking of TK and amplified the TK/GCV killing effect.This offers a new strategy to enhance the effectiveness of suicide gene therapy for the treatment of cancers.