Inductoin of Radioresistance by Overexpression of Glutathione S-Transferase K1 (hGSTK1) in MCF-7 Cells

Kim,  Jae Chul; Shin,  Sei One

J Korean Soc Ther Radiol Oncol > Volume 19(4); 2001 > Article

Original Article

The Journal of the Korean Society for Therapeutic Radiology and Oncology 2001;19(4): 381-388.

Inductoin of Radioresistance by Overexpression of Glutathione S-Transferase K1 (hGSTK1) in MCF-7 Cells

ABSTRACT

PURPOSE:
This study was conducted to assess the effects of x-irradiation on the expression of the novel glutathione S-transferase K1 gene.
MATERIALS AND METHODS:
Human glutathione S-transferase K1 (hGSTK1) DNA was purified and ligated to a pcDNA3.1/Myc-His(+) vector for the overexpression of hGSTK1 gene. MCF-7 cells were transfected with or without the recombinant hGSTK1 gene, and irradiated with 6 MV x-ray. After incubation of 14 days, cell survival was measured and compared. The expression of hGSTK1 and the effect of x- irradiation on hGSTK1 expression were also estimated in MCF-7 cells transfected with or without the hGSTK1 gene by RT-PCR.
RESULTS:
Following 2 to 12 Gy of x-irradiation, the cell survivals were higher in the MCF-7 cells transfected with the hGSTK1 gene than in those without transfection. Despite the higher cell survival in the hGSTK1-transfected cells, RT-PCR for hGSTK1 mRNA revealed no significant differences according to radiation dose, fractionation, and time after irradiation.
CONCLUSION:
The MCF-7 cells transfected with the hGSTK1 gene showed higher cell survival than those without transfection of the gene. The hGSTK1 gene might be associated with the radiosensitivity of MCF-7 cell line and further analysis should be needed.