Inhibitory Effects Of Adenovirus-mediated Biantisense Ornithine Decarboxylase And S-adenosylmethionine Decarboxylase On Proliferation And Invasion Of Esophageal Cancer Cells

Polyamine is multi-polyion of aliphatic in all living beings or organisms,including Put,Spd and Spm.It adjusts gene expression by changing DNA structure and regulating signal transduction pathway to play an important role in cell growth and differentiation.It was demonstrated that the content and biosynthesis of polyamine increased significantly in tumor cells and tissues.Therefore,inhibition of ODC and/or AdoMetDC activity might induce a depletion of intracellular polyamines,providing an effective anticancer treatment strategy.Decarboxylase(ODC) and S-adenosylmethionine decarboxylase(AdoMetDC) are the key enzymes in the biosynthesis of polyamines.We are studying the inhibitory effects of Ad-ODC-AdoMetDCas on polyamine biosynthesis,esophageal cancer cell proliferation and invasion on the ground of the successfully constructed and amplified of antisense bicistronic recombinant adenoviruses of ODC and AdoMetDC.ObjectiveTo study the inhibitory effects of Ad-ODC-AdoMetDCas on polyamine biosynthesis,lung cancer cell proliferation and invasion.Methods 1.The construction of ODC and AdoMetDC Biantisense Virus;2.Adenovirus-mediated gene transduction efficiency was assessed;3.Viable cell counting was adopted to evaluate the effect of Ad-ODC-AdoMetDCas to cell growth;4.Western Blot and High efficiency liquid chromatography(HPLC) were used to detect ODC and AdoMetDC expression and polyamine content in Eca109 cells respectively;5.Eca109 cell invasion in vitro was detected with Matrigel invasion assay;6.Ad-ODC-AdoMetDCas's anti-tumor effect was evaluated in vivo in a nude mice xenograft model.Results1.The antisense bicistronic recombinant adenoviruses of ODC and AdoMetDC are successfully constructed and amplified.2.We demonstrated that 75%of Eco 109 cells were positive for GFP at an MOI of 50 and this MOI was used for further study.3.Viable cell counting showed that Ad-ODC-AdoMetDCas inhibited the Eca109 cell proliferation(P＜0.05).4.Western blotting showed that both ODC and AdoMetDC expression were significantly inhibited in Ad-ODC-AdoMetDCas treated cells;HPLC showed that the Spm,Put and Spd content in the Eca109 cells were significantly reduced (P＜0.05).5.Gene transferred tumor cells were shown to possess markedly decreased Invasiveness(P＜0.05).6.Compared with control cells treated with Ad-GFP,Ad-ODC-AdoMetDCas significantly inhibited Eca109 tumor regression in xenograft nude mice(P＜0.05 or P＜0.01).ConclusionsAd-ODC-AdoMetDCas has significant inhibitory effects on esophageal cancer proliferation and invasion and bears therapeutic potential for the treatment of esophageal cancer.