Cell-killing effect of MAR regulating HSV-tk/GCV suicide gene system on ECA109 cells

This study aimed to investigate the cell-killing effect of HSV-tk/GCV suicide gene system driven by β-globin matrix attachment region (MAR) on ECA109 cells and its bystander effect. The integration and expression of lentivirus vectors HSV-tk and MAR-HSV-tk in ECA109 were identified using RT-PCR and Western blot; the cell survival rate and cell-killing bystander effect were detected in different time periods by MTT assay after HSV-tk and MAR-HSV-tk virus infection. Compared with the uninfected cells, the survival rates were significantly decreased with the presence of GCV after infected with HSV-tk and MAR-HSV-tk viruses for 24 h, 36 h, 48 h, 60 h and 72 h, respectively; Moreover, under the same conditions, compared with HSV-tk cells, the survival rate of cells infected with MAR-HSVtk virus was decreased more significantly and the bystander effect on tumor cell killing was more obvious. Based on the effect of HSV-tk suicide gene system, MAR could enhance the expression of HSV-tk gene. Its killing effect on esophagus cancer cells and bystander effect were more significant, suggesting that the MAR driving HSV-tk/GCV suicide gene system could more efficiently inhibit the proliferation and promote the apoptosis of tumor cells.