We investigated the anti-tumor effects of dual cancer specific-oncolytic adenovirus Ad-VP on esophageal cancer(EC). The anti-tumor activity of Ad-VP was compared with that of the control recombinant adenoviruses (Ad-GP, Ad-Apoptin, Ad-EGFP) in human esophageal cancer cell EC-109 and human normal liver cell L02 in vitro. In 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assays, the growth of EC-109 cells was slightly inhibited by Ad-GP, Ad-Apoptin and Ad-EGFE However, Ad-VP induced a significant cytotoxic effect. Infection of EC-109 cells with Ad-VP resulted in a significant induction of apoptosis of them in vitro, detected by 4',6-diamidino-2-phenylindole(DAPI) or acridine orange and ethidium bromide staining. The results of Western blot and flow cytometric assay indicate the loss of mitochondrial membrane potential(Aψm), the release of eytochrome c and the activation of caspase-3, 6 and 7 in Ad-VP infected EC-109 cells. In contrast, all these assays show almost no effects of the recombinant adenoviruses on L02 cells. These results demonstrate that the treatment of tumors with Ad-VP selectively inhibits tumor growth and induces apoptosis of esophageal cancer cells. Ad-VP may provide a novel and powerful strategy for cancer gene therapy.
SU Jia-qiangCHI Bao-rongLI XiaoLIU LeiLIU Li-mingQI Yan-xinWANG Zhuo-yueJIN Ning-yi