【摘要】 目的探讨125I粒子持续低剂量率(CLDR)内照射和60Coγ射线高剂量率(HDR)外照射对非小细胞肺癌(NSCLC)细胞株H1299的细胞生物学效应。方法 H1299细胞处于指数生长期时分别行125I粒子CLDR照射和60Coγ射线HDR照射;克隆形成实验检测细胞存活分数,流式细胞术检测细胞周期和细胞凋亡率,Western blot检测Bax、Bcl-2蛋白表达水平。结果随着照射剂量增大,125I粒子CLDR照射比60Coγ射线HDR照射抑制H1299细胞增殖效应更明显。照射剂量为4 Gy时125I粒子组H1299细胞G2/M期百分比、细胞凋亡率分别为(21.77±0.31)%、(13.79±0.50)%;同样照射剂量下,60Co照射组H1299细胞G2/M期百分比仅为(18.85±0.99)%,细胞凋亡率仅为(8.79±0.22)%(P<0.05)。125I粒子CLDR照射明显上调Bax蛋白表达,同时下调Bcl-2蛋白表达。结论 125I粒子CLDR内照射比60Coγ射线HDR外照射抑制H1299细胞增殖效应更明显。Bcl-2/Bax蛋白比失衡在125I粒子CLDR照射抗肿瘤效应中可能发挥重要作用。更多还原

【Abstract】 Objective To investigate the biological effect of125 I seeds continuous low dose rate(CLDR) irradiation and60 Co γ- ray high dose rate(HDR) irradiation on H1299 cell line of non- small cell lung cancer(NSCLC). Methods H1299 cells in exponential growth were separately irradiated with125 I seeds CLDR irradiation and60 Co γ- ray HDR irradiation. The cell survival fraction was inspected with clone formation experiment, the cell cycle and apoptosis rate was determined with flow cytometry, and the expressions of Bax and Bcl- 2 proteins were measured by Western blot method. Results With the irradiation dose increasing, the anti- proliferation effect of125 I seeds CLDR irradiation on H1299 cells became more remarkable than that of60 Co γ- ray HDR irradiation. When the irradiation dose reached 4 Gy, the G2/M phase percentage and the apoptotic ratio of H1299 cells in125 I seeds CLDR irradiation group were 21.77±0.31% and13.79±0.50% respectively, which were only 18.85±0.99% and 8.79 ±0.22% respectively in60 Co γ- ray HDR irradiation group, the difference was statistically significant(P<0.05). In125 I seeds CLDR irradiation group the expression of Bax protein was remarkably up- regulated, while the expression of Bcl- 2 protein was downregulated. Conclusion The inhibition effect of125 I seeds CLDR internal irradiation on the proliferation of H1299 cells is more obvious than that of60 Co γ- ray HDR irradiation. In125 I seeds CLDR irradiation group,the imbalance of Bcl- 2/Bax ratio may play an important role in achieving the antitumor effect.更多还原