title: [Experimental studies on the treatment of colon cancer by cytosine deaminase gene and 5-fluorocytosine].
abstract: OBJECTIVE
  To investigate the effect of cytosine deaminase (CD) gene plus 5-fluorocytosine (5-Fc) on the growth of human colon cancer xenograftin nude mice.
  
  
  METHODS
  Retroviral vector expressing CD gene was transfected into human colon cancer SW1116 cells. Expression of the transfected CD gene in SW1116 (SWCD(2)) was confirmed by RT-PCR. The cytotoxicity of 5-Fc on SW1116 was determined by MTT assay in vitro. In vivo, the CD gene expression vector was injected intratumorally and 5-Fc was given by ip injections.
  
  
  RESULTS
  In vitro, SWCD(2) cells were killed by 5-Fc with an IC(50) of 66 micromol/L while the nontrasfected SW1116 cells needed an IC(50) of 16 000 micromol/L to be killed. The growth of SWCD(2) xenografts was significantly inhibited by systemic administration of 5-Fc.
  
  
  CONCLUSIONS
  CD gene/5-Fc system is a potential gene therapy strategy for human colon cancer.
authors.affiliation: Department of Immunology, Institute of Basic Medical Science, PLA General Hospital, Beijing 100853, China. huangjh123@yahoo.com.cn
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Huang
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.forename: Chong-Hui
authors.initials: CH
authors.lastname: Li
authors.forename: Da-Guang
authors.initials: DG
authors.lastname: Zhong
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Lü
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D003131:Combined Modality Therapy; D043525:Cytosine Deaminase / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005437:Flucytosine / Q000494:pharmacology / Q000627:therapeutic use*; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D020128:Inhibitory Concentration 50; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D012190:Retroviridae / Q000235:genetics; D014162:Transfection
chemical_list: D005437:Flucytosine; D043525:Cytosine Deaminase