Construction of a karyotic expression vector involving HSV-1 thymidine kinase under the control by survivin promoter and its potential use in ling gene therapy

Objective: To construct a lung cancer specific the herpes simplex virus 1 thymidine kinase(HSV1-TK) expression vector regulated by survivin promoter(SURV) and detect its activation and potential to inhibit the grow of lung cancer in vivo.Methods: Plasmid pGL3-TK was obtained by substituting the luciferase cassette with a PCR product corresponding to TK with flanking Nco Ⅰ and Xho Ⅰ sites.To obtain the pSURV-TK and pCMV-TK two versions,the SURV and CMV cassettes were excised with Bgl Ⅱ and Hand Ⅲ and cloned into the respective sites of the vector.Recombinant plasmid pSURV-TK and pCMV-TK were transfected into survivin positive or negative cell lines by the means of lipofectamine.The expression of HSV1-TK was tested by Western Blotting,Ganciclovir cytotoxicity assay to evaluate the activation of SURV and in vivo tumorigenesis experiments to explore the potential using this vector to treat lung cancer.Results: The vector pSURV-TK has been successfully constructed which can not only express the TK protein indentified by Western Blotting,but also show its enzyme activation related to the concentration of ganciclovir and suppression of tumor growth in vivo.Conclusion: Survivin promoter can effectively drive the HSV1-TK to express.The expression of TK gene will be confined just within the site of tumor.This presented a new way of employment sucide genes for treatment of lung cancer.