title: [Anti-tumor and bystander effects of cationic liposome-mediated CD/5-FC suicide gene system combined with interferon-gamma in vivo].
abstract: OBJECTIVE
  To study the antitumor and distant bystander effects of cationic liposome-mediated cytosine deaminase (CD)/5-fluorocytosine (5-FC) suicide gene system combined with interferon-gamma (IFN-gamma) in vivo.
  
  
  METHODS
  Murine hepatoma 22 (H22) cells transfected by CD gene were inoculated subcutaneous in Kunming mice in the left axillary region, and the H22 cells without CD gene transfection were inoculated in the right axillary region. The mice were randomly divided into 4 groups and treated with normal saline , 5-FC, IFN-gamma, and 5-FC+ IFN-gamma on a daily basis. The tumor inhibition and distant bystander effects were observed in the mice.
  
  
  RESULTS
  Exposure of CD gene-transfected tumor to 5-Fc resulted in obvious tumor growth inhibition with an inhibition rate of 78.38%, which was significantly increased to 93.21% (P<0.01) with 5-Fc +IFN-gamma treatment. A notable distant bystander effect in the CD/5-FC suicide gene system was observed in vivo, with a tumor inhibition rate of was 54.42%; when combined with IFN-gamma, the inhibition rate increased significantly to 87.57% (P<0.05).
  
  
  CONCLUSIONS
  When combined with IFN-gamma, CD/5-FC suicide system has stronger anti-tumor and distant bystander effects. CD/5-FC suicide gene system combined with IFN-gamma may provide a potential therapy for malignant tumors.
authors.affiliation: Department of General Surgery, Zhongshan Hospital, Xiamen University, Xiamen, China. luoqi@medmail.com.cn
authors.forename: Qi
authors.initials: Q
authors.lastname: Luo
authors.forename: Yi-zhuo
authors.initials: YZ
authors.lastname: Lu
authors.forename: Guo-yan
authors.initials: GY
authors.lastname: Liu
authors.forename: Son-en
authors.initials: SE
authors.lastname: Zhang
mesh_terms: D000818:Animals; D024201:Bystander Effect; D002412:Cations / Q000737:chemistry; D043525:Cytosine Deaminase / Q000235:genetics*; D005437:Flucytosine / Q000494:pharmacology*; D041722:Genes, Transgenic, Suicide / Q000235:genetics*; D015316:Genetic Therapy / Q000379:methods; D007371:Interferon-gamma / Q000627:therapeutic use*; D008081:Liposomes; D008114:Liver Neoplasms, Experimental / Q000628:therapy*; D008297:Male; D051379:Mice; D011897:Random Allocation
chemical_list: D002412:Cations; D008081:Liposomes; D007371:Interferon-gamma; D005437:Flucytosine; D043525:Cytosine Deaminase