摘要
目的研究二氢青蒿素(dihydroartemisinin,DHA)联合放疗对人肺腺癌GLC-82细胞周期和凋亡的影响及其机制。方法 MTT法检测不同浓度DHA分别在24、48、72 h对GLC-82细胞的抑制作用;克隆形成实验分析,多靶单击拟合模型方程计算放射增敏比,评价增敏效果;流式细胞术检测DHA联合放疗对GLC-82细胞周期和凋亡的影响;Western blot检测P53、P21、Bcl-2和Bax蛋白的表达。结果不同浓度DHA(4、8、16、32、64、128μg/mL)作用24、48和72 h的IC50值分别为:38.25、20.58、10.36μg/mL,对GLC-82细胞的毒性有明显剂量和时间依赖性,抑制率较空白对照组明显增加(P<0.01,P<0.05);DHA对GLC-82细胞具有放射增敏作用,其增敏比为1.4。DHA联合放疗可使GLC-82细胞周期的构成发生明显的变化并诱导细胞凋亡,凋亡率为21.5%,与空白对照组比较,差异有统计学意义(P<0.05)。Western blot表明,DHA联合放疗作用GLC-82细胞后P53和P21的蛋白水平表达增加,同时下调Bcl-2蛋白表达(P<0.01,P<0.05)。结论 DHA对肺腺癌GLC-82细胞有较强的细胞毒性和放射增敏作用,其作用机制可能是使GLC-82细胞生长停滞在G0/G1期并诱导细胞凋亡,使S期细胞比例降低;使P53功能恢复,通过抑制Bcl-2蛋白的表达促使凋亡,从而起到杀伤肿瘤的作用。
Objective To study the effect of Dihydroartemisinin （DHA） combined irradiation on the apoptosis of human lung cancer GLC-82 cells and to study its mechanism. Methods The growth inhibition rate of GLC-82 cells acted by different concentrations DHA was detected using MTT assay at 24, 48, and 72 h, respectively. Clone forming test was used. With multi-target single-hit model, the radiosensitization effect was assessed by calculating sensitizing enhancement ratio （SER）. The effect of DHA combined irradiation on the apoptosis of GLC-82 cell cycle distribution and apoptosis were measured by flow cytome- try. The protein expression of p53, p21, Bcl-2, and Bax were detected by Western blot. Results Different concentrations DHA （4, 8, 16, 32, 64, and 128 iJLg/mL） had cytotoxicity on GLC-82 cells. The IC50 for 24, 48, and 72 h was 38.25, 20.58, and 10.36 μg/mL, respectively, in obvious dose- and time-dependent manner. The growth inhibition rate was more significantly increased than that of the blank control group （P 〈 0.01, P 〈0.05）. DHA had sensitization enhancement effect on GLC-82 cells, with SER of 1.4. DHA combined irradiation could obviously change the structure of GLC-82 cells cell cycle and induce apoptosis （with the apoptosis rate of 21.5%）, which was significantly different from that of the blank control group （P 〈 0.05）. Western blot showed the expression of p53 and p21 protein could be increased by DHA combined irradiation, and the expression of Bcl-2 protein down-regulated （P 〈0.01, P 〈0.05）. Conclusions DHA had stronger cytotoxicity and radiosensitization on GLC-82 cells. Its mechanisms might lie in making the arrestof GLC-82 cells＇ growth at G0/G1 phase, decreasing the ratio of cells at S phase, restoring the function of p53, decreasing the expression of Bcl-2 protein, and inducing apoptosis in GLC-82 cells.
出处
《中国中西医结合杂志》
CAS
CSCD
北大核心
2014年第10期1220-1224,共5页
Chinese Journal of Integrated Traditional and Western Medicine
