An in Vitro Study of the RV-HSV-TK/GCV Gene Therapy System in Breast Carcinoma

Objective In order to study the killing effect and the by stander effect of retrovirus mediated herpes simplex virus thymidine kinase(HSV TK)gene combined with ganciclovir(GCV) on mice breast carcinoma cells.Methods GINaTK retroviral vector containing HSV TK gene was transduced into PA317 retroviral packaging cells by lipofectin,PA317 cells transfected with HSV TK gene were then screened by G418 medium,and resistant clones(named PA317/TK) were identified by PCR.Mice breast carcinoma cell line MA782/5S 8102 was infected by the high titer viral supernatant.MA782/5S 8102/TK cells and MA782/5S 8102 cells were mixed in different ratio and cultured in 96 well plates.After culture for 24 hours,10 μg/ml GCV was added into half of the wells,the others as controls.4 days later,viability of the cells was obtained by MTT test.Results Experimental results revealed that stable virus producing cell line was established after GINaTK retroviral vector was transferred into PA317,and MA782/5S 8102/TK cells expressing the HSV TK gene were obtained successfully.As showing by mixed culture of MA782/5S 8102/TK cells and MA782/5S 8102 cells in different ratio,when the percentage of MA782/5S 8102/TK cells reached 10%,the killing rate of tumor cells was almost 50%.Conclusion The HSV TK gene can be stable expressed in mice breast cancer line MA782/5S 8102 under the mediation of retrovirus,and the bystander effect of HSV TK/GCV system can improve the killing effect of cancer cells.