title: [Expression of canstatin gene in human lymphocytes and its inhibitory effect on growth and metastasis of Lewis lung carcinoma].
abstract: BACKGROUND
  In recent years, many progresses have been made in molecular target therapy for lung cancer, in which anti-angiogenic target therapy is a hot spot drawing researchers' attention. The aim of this study is to explore the expression of canstatin gene transfected into human lymphocytes and its inhibitory effect on growth and metastasis of Lewis lung carcinoma.
  
  
  METHODS
  The eukaryotic expression vector of pCMV-Script and the recombinant pCMV-Script/Canstatin vector were separately transfected into lymphocytes by electroporation. The expression of canstatin protein in supernatant of lymphocyues was examined by SDS-PAGE assay. Furthermore, Lewis lung carcinoma cells were subcutaneously inoculated to C57BL mice to make animal model of tumor. When the transplanted tumors on the mice developed to 1cm³, the 30 mice were randomized into 3 groups, which were injected with 0.2mL supernatant of lymphocytes transfected with recombinant vector or naked vector, or 0.2mL NS respectively. After the treatment for 14 days, the size and pathological section of subcutaneous tumors were observed, and the number of pulmonary metastatic node was calculated.
  
  
  RESULTS
  Canstatin protein was found in supernatant of the lymphocytes in the recombinant vector group by SDS-PAGE assay. After the treatment, the tumor size in the recombinant vector group (1.49cm³±0.18cm³) was significantly smaller than that in the naked vector group (2.44cm³± 0.19cm³) and NS group (2.53cm³±0.18cm³) (P=0.000). The numbers of pulmonary metastatic node were 3.40±1.14, 7.60±2.61 and 7.60±2.41 in the recombinant vector group, naked vector group and NS group respectively (recombinant vector group vs the other two groups, P=0.013).
  
  
  CONCLUSIONS
  The pCMV-Script/Canstatin vector can express canstatin protein in human lymphocytes. Canstatin has strongly inhibitory effect on growth and metastasis of mouse Lewis lung carcinoma.
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, The Third Military Medical University, Chongqing 400037, P.R.China.
authors.forename: Weizhong
authors.initials: W
authors.lastname: Lu
authors.forename: Xiwen
authors.initials: X
authors.lastname: Wang
authors.forename: Guijun
authors.initials: G
authors.lastname: Huang
authors.forename: Yuying
authors.initials: Y
authors.lastname: Li
authors.forename: Shicang
authors.initials: S
authors.lastname: Yu
authors.forename: Jin
authors.initials: J
authors.lastname: Li
authors.forename: Guisheng
authors.initials: G
authors.lastname: Qian