HSVTK/GCV自杀基因系统治疗乳腺癌的研究

A Study of the RV-HSV-TK/GCV Suicide Gene Therapy System in Breast Carcinoma

目的 探讨HSV TK/GCV自杀基因系统对小鼠乳腺癌细胞系MA782 / 5S 810 2体外及体内杀伤作用及其产生的旁观者效应。方法 采用脂质体转染法将GINaTK载体转入包装细胞PA317。取病毒上清液感染小鼠乳腺癌细胞MA782 / 5S 810 2 ,得到带有HSV TK基因的MA782 / 5S 810 2 /TK细胞 ,并将其分别用于体外和体内实验。结果 载体HSV TK导入了PA317细胞。体外实验结果显示 ,当MA782 / 5S 810 2 /TK细胞数占混合细胞 10 %时 ,低浓度 (10 μg/ml)的GCV就可将 5 0 %左右的肿瘤细胞杀死。体内实验结果显示GCV可明显抑制MA782 / 5S 810 2 /TK细胞在BALB/C小鼠体内的肿瘤形成。实验组肿瘤组织与对照组相比存在明显的病理学改变。结论 逆转录病毒可介导HSV TK基因转入小鼠乳腺癌细胞MA782 / 5S 810 2并获稳定表达 ,HSV TK/GCV自杀基因系统在体内外对乳腺癌细胞均有杀伤作用 ,且存在明显的旁观者效应。

Objective To study the killing effect in vitro and in vivo and the bystander effect of HSV-TK/GCV suicide gene system on mice breast carcinoma cells MA782/5S-8102. Methods GINaTK retroviral vector containing HSV-TK gene was transduced into PA317 packaging cell by lipofectin.Mice breast carcinoma cell line MA782/5S-8102 was infected by high titer viral supernatate. PCR Was resorted to demonstrate the successful transduction of the HSV-TK gene. MA782/5S-8102 /TK cells and MA782/5S-8102 cells were used in study in vitro and in vivo study. Results PA317 cells were transfected successfully with HSV-TK gene by lipofectin(named PA317/TK). The results revealed that stable virus producing cell line was established and MA782/5S-8102/TK cells expressing the HSV-TK gene were obtained successfully. In vitro, when the ratio of MA782/5S-8102 /TK cells reached to 10%,the tumor cell-killing proportion was almost 50%. In vivo, GCV could suppress tumor formation of the MA782/5S-8102/TK cells. Tumors treated with GCV revealed different histopathological features compared with the control tumors. The expression of HSV-TK gene was detected by RT-PCR. Conclusion The test showed that the HSV-TK gene can be transducted into mice breast cancer line MA782/5S-8102 under the mediation of retrovirus and be stable expressed, HSV-TK/GCV suicide gene therapy system could improve the antitumor efficiency. The bystander effect could be observed in HSV-TK/GCV system in vitro and in vivo.