Abstract:Objective:To study the selective expression and eradicating effect of recombinant plasmid vector DTA containing transcriptional regulation sequence of human breast cancer DF3 /MUC1 promoter (PGL3-DF3-DTA) on DF3 positive breast carcinoma cell lines. Methods :The MCF-7 and MDA-MB231 breast carcinoma cell lines were transplanted into the dorsal subcutaneous tissue of nude mice in different groups. The mice was subcutaneously injected with recombinant plasmid PGL3-DF3-DTA 7 days after transplantation and the animals were sacrificed 29 days after transplantation. The tumors were excised and the weight and volume were determined. The expression of DTA was detected by reverse transcription-polymerase chain reaction (RT-PCR). Results:Recombinant plasmid vector PGL3-DF3-DTA was expressed in xenograft of MCF-7 breast carcinoma cell lines, and the growth of tumor was significantly inhibited. Conclusions:Recombinant plasmid vector PGL3-DF3-DTA has selective expression and eradicating effect on DF3-positive breast cancer cell lines.