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Experimental studies onPNP suicide gene therapy of hepatoma

  • Cai Xiaokun
  • Zhou Junli
  • Lin Jusheng
  • Sun Xuemei
  • Xue Xiulan
  • Li Chao
Article

Summary

To investigate the killing effect ofPNP/MeP-dR suicide gene system on hepatoma cells, pcDNA3. 0/PNP, an eukaryotic expression vector harboringE. coli PNP gene, was transfected into human hepatoma HepG2 cells by liposome-mediated method. A HepG2 cell line with stablePNP gene expression, HepG2/PNP, was established with presence of G418 selection. The cell growth curves were determined with trypan blue staining. The sensitivity of HepG2/PNP to MeP-dR and bystander effects were assayed by MTT and FCM methods. The enzymatic activity of the product ofPNP gene was determined by HPLC method. The cytotoxic effects of MeP-dR on HepG2/PNP cells were obvious (IC50=4.5 μmol/L) and all HepG2/PNP cells were killed 4 days after the treatment with 100 μmol/L MeP-dR. In mixed cultures containing increasing percentages of HepG2/PNP cells, total population killing was demonstrated when HepG2/PNP cells accounted for as few as 5% of all HepG2 cells 8 days after the treatment with 100μmol MeP-dR. High-pressure liquid chromatography (HPLC) demonstrated that thePNP enzyme could convert MeP-dR into 6-MP.PNP/MeP-dR suicide gene system had an advantage over traditional suicide gene systems for hepatoma gene therapy. Our e results suggest that high-level bystander effects of this system result in significant anti-tumor responses to hepatoma gene therapy, especiallyin vivo.

Key words

PNP/MeP-dR suicide gene system hepatoma gene therapy 

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Copyright information

© Springer 2005

Authors and Affiliations

  • Cai Xiaokun
    • 1
  • Zhou Junli
    • 2
  • Lin Jusheng
    • 1
  • Sun Xuemei
    • 1
  • Xue Xiulan
    • 1
  • Li Chao
    • 1
  1. 1.Institute for Liver Disease of Tongji Hospital, Tongji School of MedicineHuazhong University of Science and TechnologyWuhanChina
  2. 2.Department of Microbiology, Tongji School of MedicineHuazhong University of Science and TechnologyWuhanChina

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