| The polyamines are positively charged aliphatic amines at physiological.Polyamines are known to be critically involved in cell growth and have been implicated in the process of cell transformation.The level of polymines are high in cancer cells and tissues,and rapid tumor growth has been associated with remarkable elevation of polyamine biosynthesis and accumulation. Decarboxylase(ODC)and S-adenosylmethionine decarboxylase (AdoMetDC),the key enzymes in the biosynthesis of polyamines, are found to increase in cancer cells especially lung cancers.We are studying the inhibitory effects of Ad-ODC-AdoMetDCas on polyamine biosynthesis,lung 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.Methods1.The construction and amplification of antisense bicistronic recombinant adenoviruses of ODe and SAMDC.2.Adenovirus-mediated gene transduction efficiency was assessed with counting GFP-positive cells using trypan blue.3.Western Blot and HPLC were used to detect ornithine decarboxylase(ODC)and S-adenosylmethionine decarboxylase (AdoMetDC)expression and polyamine content in A-549 cells respectively. 4.Viable cell counting and cell cycle analysis were adopted to evaluate cell growth and cell cycle distribution.5.A-549 cell invasion in vitro was detected with Matrigel invasion assay.Results1.The antisense bicistronic recombinant adenoviruses of ODC and AdoMetDC are successfully constructed and amplified.2.Approximate 75%of A-549 cells were infected with Ad-ODC-AdoMetDCas when multiplicity of infection reached 50.3.Our study demonstrated that Ad-ODC-AdoMetDCas vector-mediated gene transfer inhibited tumor cell growth through the blockade of polyamine synthesis pathway.4.The tumor cells were arrested at cell cycle G1 phase after gene transfer.5.Gene transferred tumor cells were shown to possess markedly decreased invasiveness.ConclusionAd-ODC-AdoMetDCas has significant inhibitory effects on lung cancer cell proliferation and invasion and bears therapeutic potential for the treatment of lung cancer. |
