Targeted killing of colorectal tumor cells by lentiviral constructs containing CD/TK suicide genes and KDR promoter / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the selective killing of colorectal tumor cells by lentivirus-mediated double suicide gene under the regulation of KDR promoter.</p><p><b>METHODS</b>293T packaging cells were transfected with the plasmid FGW-KDRP-CD/TK to obtain the infectious viruses. KDR-expressing LoVo cells and LS174T cells that did not produce KDR were transfected with the recombinant virus, and the transfection efficiency was evaluated by the fluorecence microscope. RT-PCR was employed to examine the expression of CDglyTK. After treatment of the cells with 5-FC and GCV, the killing effects on the two cell lines were evaluated.</p><p><b>RESULTS</b>The recombinant construct showed similar infection rate of the two cell lines. RT-PCR demonstrated that CDglyTK gene was expressed only in LoVo cells infected with FGW-KDRP-CD/TK but not in LS147T cells, and the sensitivity of the two cell lines to the prodrugs was significantly different (P<0.001). The killing effect of the double suicide gene was much stronger than that of single suicide gene administered (P<0.001).</p><p><b>CONCLUSION</b>The double suicide gene driven by KDR promoter has specific killing effect on the KDR-expressing colorectal tumor cells.</p>