LIU Fang,WU Mei,ZHANG Zun-zhen.Study on the radiosensitivity of lung cancer cells mediated by hOGG1 ribozyme[J].Chinese Journal of Radiological Medicine and Protection,2010,30(2):133-137 |
Study on the radiosensitivity of lung cancer cells mediated by hOGG1 ribozyme |
Received:June 04, 2009 |
DOI: |
KeyWords:hOGG1 gene Radiosensitivity Radiation Ribozyme |
FundProject:国家自然科学基金(30571535,30872079) |
Author Name | Affiliation | E-mail | LIU Fang | Department of Environmental Health, School of Public Health, Sichuan University, Chengdu 610041, China | | WU Mei | Department of Environmental Health, School of Public Health, Sichuan University, Chengdu 610041, China | | ZHANG Zun-zhen | Department of Environmental Health, School of Public Health, Sichuan University, Chengdu 610041, China | zhangzunzhen@163.com |
|
Hits: 3563 |
Download times: 2347 |
Abstract:: |
Objective To study the mechanism of hOGG1 down-regulation mediated by hOGG1 ribozyme on increasing the radiosensitivity to tumor cells by observing the damage effects induced by 60Co γ -rays on human lung cancer cell line.Methods Human lung adenocarcinoma A549 cells,A549-P cells transfected with empty pcDNA3.1 plasmid and A549-R cells transfected with pcDNA3.1-RZ plasmid in which hOGG1 ribozyme was constructed previously were utilized as a model system. The three kinds of cells were exposed to different doses of 60Co γ -rays. The level of cellular reactive oxygen species (ROS), the cell viability, the chromosome damage as well as DNA damage and repair were examined respectively. Results The cell viability decreased significantly among A549, A549-P and A549-R cells after exposure to 60Co-γ rays with a dose-response relationship(r =-0.984, -0.978,-0.975, P<0.05), and the IC50 in A549-R cells (9.37±0.24) was statistically lower than that in A549 cells(12.98±0.44, t=-12.48, P<0.05).The ROS level, the rate of micronucleus formation and DNA damage in all three kinds of cells were enhanced after exposure to 60Co γ - rays, in which A549-R cells presented the most remarkable effect compared with A549 and A549-P cells. Similarly, DNA damage in A549-R cells was also more severe and more difficult to be repaired than that in A549 and A549-P cells at the same dose.Conclusions 60Co γ -rays can induce DNA and chromosome damage in A549 cells through the ROS accumulation, leading to the reduction of the cell viability. However, all effects detected were more remarkable in A549-R cells in which hOGG1 was down-regulated mediated by ribozyme, suggesting that the deficiency in hOGG1 might increase the radiosensivity in tumor cells. |
HTML View Full Text View/Add Comment Download reader |
Close |
|
|
|