Expression of constructed human mutant p27 gene recombinant adenovirus in colon cancer cell line SW480 / 中国组织工程研究

ABSTRACT

BACKGROUND: The incidence rate of colon cancer is on an obvious increase. Previous treatments are primarily surgical therapy; radiotherapy and chemotherapy. Gene therapy has been applied in the clinical practice for treating colon cancer.OBJECTIVE: To construct replication deficient hp27mt recombinant adenovirus and detect its expression in SW480 cell in order to investigate the viability of gene therapy based on adenovirus and study the anti-tumor characteristic of mutant p27.DESIGN: A non-randomized controlled trial.SETTING: Department of Gastroenterology, Affiliated People' s Hospital of Yunyang Medical College, Institute of Clinical Medical Science of Yunyang Medical College; Department of Gastroenterology, Zhongnan Hospital of Wuhan University.MATERIALS The experiment was conducted in the Institute of Clinical Medicine, Yunyang Medical College from January 2002 to September 2003. Restriction endo-nucleases Age Ⅰ, Nhe Ⅰ, Kpn Ⅰ, Pac Ⅰ and Pme Ⅰ;Taq polymerase; T4 DNA ligase; Western blot kit; mouse anti-human p27kipl polyclonal antibody, horseradish-peroxidase conjugated goat anti mouse second IgG monoclonal antibody; pORF9-hp27mt plasmid, adenovirus framework plasmid pAdeasy-1, shuttle plasmid pShuttle-CMV, LacZ recombinant adenovirus Ad-LacZ, liposome, colon cancer cell line SW480.METHODS: hp27mt was excised from vector pORF9-hp27mt by restriction endonucleases, and inserted into shuttle plasmid pShuttle-CMV after two cycles of subclone, forming plasmid pShuttle-CMV-hp27mt. Then it was transformed by linear terminus(cut by PmeI) plasmid pShuttle-CMV-hp27mt into competent E. coli BJ5183 which contained adenovirus framework plasmid pAdeasy-1 to ensure that homologous recombination occurred. After correct identification of the transformant, it was digested by PacⅠ and transfected Ad293 cells, and packed into recombinant adenovirus Ad-hp27mt. Recombinant adenovirus was identified by polymerase chain reColon cancer cell line SW480 was infected with recombinant adenovirus Ad-p27mt, and expression of p27 protein was detected by Western blot.of expressed p27 protein after Ad-p27mt transfected colon cancer cell.novirus framework plasmid pAdeasy-1 with pShuttle-CMV-hp27mt, 30%combinant adenovirus DNA contained the target gene. Virus titer of the recancer cells, p27 was highly expressed in SW480 cells, as compared to low expression in non-transfected cells and Ad-LacZ transfected cells.CONCLUSION: Adenovirus, a type of gene transferring vector, can efficiently mediate p27 expression in tumor cells, which provides effective gene transfecting carrier for treating colorectal cancer with mutation p27 gene.