低剂量电离辐射预处理对高剂量辐射诱导的肝癌细胞hepG2细胞周期阻滞的影响  

Effects of low priming dose irradiation on cell cycle arrest of HepG2 cells caused by high dose irradiation

作　　者：夏景光[1] 李文建[1] 王菊芳[1] 郭传玲[1] 金晓东[1] 高清祥[2] 

机构地区：[1]中国科学院近代物理研究所 [2]兰州大学生命科学学院,兰州730000

出　　处：《辐射研究与辐射工艺学报》2005年第1期49-52,共4页Journal of Radiation Research and Radiation Processing

基　　金：国家自然科学基金(10335050)重点资助;国家重大基础研究前期研究专项(2003CCB00200)资助

摘　　要：以人肝癌细胞 hepG2 为研究对象,用流式细胞术测定并分析了低剂量 γ 射线(5cGy)预照射对高剂量照射(3Gy)诱导的细胞周期阻滞的影响。结果显示:(1)低剂量照射可引起 hepG2 细胞在 G2/M 期短暂累积(至照射后 4h);(2)低剂量照射促进 hepG2 细胞的生长;(3)高剂量照射后,hepG2 细胞的 G2期发生阻滞,而 S 期只发生短暂延迟;(4)与单纯高剂量照射相比,低剂量照射预处理后 4h 给予高剂量照射可进一步促进hepG2 细胞在 G2/M 期累积,但预处理后 8h 给予高剂量可促进细胞通过 G2/M 期。实验结果表明,低剂量照射预处理对高剂量照射诱导的细胞周期阻滞的影响,取决于两次照射的时间间隔。Human hepatoma cells hepG2 were irradiated twice by 60Co γ-rays with a priming dose of 5 cGy and a higher dose of 3 Gy performed 4 h or 8 h after the low dose irradiation. Effects of the priming dose irradiation on cell cycle arrest caused by high dose were examined with flow cytometry. Cells in G2/M phase accumulated temporarily after the 5 cGy irradiation, and proliferation of tumor cells was promoted significantly by the low dose irradiation. After the 3 Gy irradiation, G2 phase arrest occurred, and S phase delayed temporally. In comparison with 3 kGy irradiation only, the priming dose delivered 4 h prior to the high dose irradiation facilitated accumulation of hepG2 cells in G2/M phase, whereas the priming dose delivered 8 h prior to the high dose irradiation helped the cells to overcome G2 arrest. It was concluded that effects of the priming dose treatment on cell cycle arrest caused by high dose irradiation were dependent on time interval between the two irradiations.

关 键 词：低剂量辐射 细胞周期阻滞 肝癌细胞 

分 类 号：Q691[生物学—生物物理学]