HSV_1-tk/GCV系统联合Topotecan治疗人卵巢癌的动物实验研究

HSV_1-tk/GCV suicide gene therapy in combination with Topotecan in nude mice with human ovarian cancer

目的探讨Topotecan能否增强HSV1-tk/GCV自杀基因系统对卵巢癌的体内治疗作用。方法先用携带tk基因的重组逆转录病毒上清转染人卵巢癌细胞系SKOV-3,用含G418的培养液筛选抗性克隆(命名为SKOV-3/TK)。PCR方法检测tk基因整合情况。用SKOV-3细胞建立荷瘤鼠模型作为对照组和Topotecan组。用SKOV-3与SKOV-3/TK细胞按8∶2比例混合细胞建立者为HSV1-tk/GCV组和HSV1-tk/GCV联合Topotecan组;从用药第1天开始每5天测量肿瘤体积一次,至用药结束后一周,绘制肿瘤生长曲线,计算抑瘤率,并取瘤组织做病理学检查。结果与对照组比较,HSV1-TK/GCV组和Topotecan组、联合用药组抑瘤率分别为38.8%、25.3%和89.7%,差异均有显著性,P<0.01。组间两两比较差异亦有显著性,P<0.01。病理显示实验组出现不同程度点、片状坏死,以联合用药组为重。结论HSV1-tk/GCV自杀基因系统具有强大的杀伤肿瘤效应及旁观者效应,联合Topotecan化疗将起到协同作用。

Objective To study whether Topotecan could enhance the killing effect of a suicide gene therapy sy-stem of HSV_1-tk/GCV (herpes simplex ivirus thymidine kinase / ganciclovir ) for ovarian cancer in vivo. Methods Human ovarian cancer cell line SKOV-3 was transfected with the recombinant retrovirus , containing HSV_1-tk gene. Following selection by G418 medium, and resistant clones (named SKOV-3/TK) were identified by PCR. Subcutaneous tumor models were induced in nude mice by subcutaneous injection with different cells. Nude mice subcutaneous injection with SKOV-3 cells were used as blank control and Topotecan group. Those subcutaneous injection with the mixture of 80% SKOV-3 cells and 20% SKOV-3/TK cells were used as HSV_1-tk/GCV group and HSV_1-tk/GCV combined with Topotecan group. The average tumor volume were investigated. Results Compared with control group, tumor growth inhibition rates of HSV_1-tk/GCV 、Topotecan and the combination group were 38.8%、25.3% and 89.7% respectively. Which were significant different,P<0. 01. The extensive necrosis was observed in the treated mice of the combination therapy group. Conclusion HSV_1-tk/GCV suicide gene therapy system has a powerful killing effect and a bystander effect for ovarian cancer ,and a synergistic anticancer effect was observed when combined with Topotecan.