title: [Efficacy of antitumour colon cancer cell vaccine modified by Escherichia coli cytosine deaminase gene].
abstract: OBJECTIVE
  To evaluate the efficacy of antitumour colon cancer cell vaccine modified by escherichia coli cytosine deaminase (EC-CD).
  
  
  METHODS
  Mouse colon cancer cell vaccine CT26/CD was established by gene modification using retrovirus plasmid pLCDSN. Its tumorigenicity and effect on liver metastasis model established with wild-type colon cancer were evaluated.
  
  
  RESULTS
  CT26/CD was established successfully and proliferated in medium containing 0.6 g/L G418 stably. EC-CD gene expression on these mutant cells was confirmed by RT-PCR. These mutant cells were more sensitive to 5-fluorocytosine (5-FC) compared with the wild-type ones (P=0.000), and presented excellent bystander effect. CT26/CD had the same tumorigenicity as its parental cells (P=0.892). CT26/CD, combined with the prodrug 5-FC, could inhibit tumor progress and live metastasis, and prolonged the survival of the liver metastasis model animals (P=0.000).
  
  
  CONCLUSIONS
  The colon cancer cell vaccine modified by EC-CD presented anti-tumor effect in vivo, when treated with the prodrug.
authors.affiliation: Department of Gastrointestinal Surgery, The First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China. shenlz@163.com
authors.forename: Li-zong
authors.initials: LZ
authors.lastname: Shen
authors.forename: Jian-hua
authors.initials: JH
authors.lastname: Wang
authors.forename: Hai-quan
authors.initials: HQ
authors.lastname: Wang
authors.forename: Yi-bing
authors.initials: YB
authors.lastname: Hua
authors.forename: Wen-xi
authors.initials: WX
authors.lastname: Wu
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D019496:Cancer Vaccines / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000628:therapy*; D043525:Cytosine Deaminase / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D019496:Cancer Vaccines; D029968:Escherichia coli Proteins; D043525:Cytosine Deaminase; C468827:codA protein, E coli