title: [Effects of Gax gene transfection on proliferation and expression of proto-oncogenes in A549 cells].
abstract: BACKGROUND
  Lung cancer is the leading cancer of malignant tumor in China.It is the direction that poeple make efforts to seek gene therapy of lung cancer. The aim of this study is to explore the effects of transfected growth arrest-specific homeobox gene (Gax gene) on the proliferation and expressions of c-fos and c-jun mRNA in A549 cells.
  
  
  METHODS
  A549 cells were transfected with Gax gene by adenovirus. Expressions of Gax mRNA and protein were detected by RT-PCR and immunocytochemistry. The expressions of c-fos and c-jun mRNA were evaluated by RT-PCR. The proliferation inhibition effect of Gax transfection on A549 cells was evaluated by MTT assay.
  
  
  RESULTS
  Only in the A549 cells transfected with Gax gene the Gax expression was confirmed by RT-PCR and immunocytochemistry. Compared with that in the control group, c-fos and c-jun mRNA level decreased significantly in Gax-transfected A549 cells (t=7.755, P < 0.01; t= 5.938 , P < 0.01). MTT assay showed that the proliferation inhibition rates of A549 cells transfected by Ad-Gax for 24h, 48h and 72h were (47.35±5.36)%, (54.96±1.78)%, and (65.39±5.11)% respectively. And these proliferation inhibition rates were significantly higher than those in the control group (Chi-Square=7.152, 9.431 and 12.847, P < 0.01).
  
  
  CONCLUSIONS
  Gax gene can inhibit the proliferation of A549 cells. Its molecular mechanism may be through down-regulating the expressions of c-fos and c-jun.
authors.affiliation: Institute of Respiratory Diseases, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R.China.
authors.forename: Shijin
authors.initials: S
authors.lastname: Xia
authors.forename: Guisheng
authors.initials: G
authors.lastname: Qian
authors.forename: Mingdong
authors.initials: M
authors.lastname: Hu
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Tan