活性氧水平与食管癌细胞对As_2O_3促凋亡作用的敏感性关系研究

THE APOPTOTIC SUSCEPTIBILITY OF ESOPHAGEAL CELLS TO ARSENIC TRIOXIDE IS DETERMINED BY CELLULAR REACTIVE OXYGEN SPECIES LEVEL

目的 :探索食管癌细胞株 EC/ CU HK1、EC/ CU HK1(As- )对三氧化二砷 (As2 O3 )促凋亡作用敏感性与细胞活性氧 (reactive oxygen species,ROS)水平的关系。方法 :以二甲萘醌(DMNQ)孵育 EC/ CU HK1、EC/ CU HK1(As- )细胞 ,双氢 -乙酰乙酸二氯荧光黄 (2 ,7- dichlorodihy-drofluorescein diacetate,DCFH- DA)及双氢罗丹明 12 3(dihydrorhodamine12 3,DHR)捕获 ROS,流式细胞仪检测两种细胞 ROS水平的差异。 As2 O3 单独或联用 DMNQ孵育 EC/ CU HK1、EC/ CUHK1(As- )细胞 ,流式细胞仪 Tunel法分析两种细胞凋亡敏感性的差异及其在用药前后的变化。结果 :EC/CUHK1的 ROS水平明显高于 EC/ CUHK1(As- ) ,DMNQ可提高 EC/ CU HK1、EC/ CU HK1(As- )的ROS水平 ,诱发 EC/ CUHK1(As- )对 As2 O3 的敏感性 ,增强 As2 O3 促 EC/ CU HK1(As- )细胞凋亡的效应。过氧化氢酶 (catalase)可逆转 DMNQ的效应。结论 :食管癌细胞株 EC/ CUHK1、EC/ CUHK1(As- )对 As2 O3 促凋亡的敏感性决定于细胞固有的

Objective:To explore the relationship between the susceptibility to arsenic trioxide (As 2O 3) induced apoptosis of esophageal cells and the level of reactive oxygen species(ROS)of cells.Methods:Flow cytometry and electron microscopy were applied to identify apoptosis, and dihydrorhodamine123 and 2,7-dichlorodihydrofluorescein diacetate 2,7-dichlorodihydrofluorescein diacetate were used to display the ROS level of cells. As 2O 3 alone or in combination with 2,3-dimethoxy-1,4-naphthoquinone (DMNQ) were used to induce cell apoptosis. The results showed that EC/CUHK1 cells possessed higher level of ROS than EC/CUHK1(As-) cells.Results:DMNQ raised ROS levels of EC/CUHK1 and EC/CUHK1(As-) cells, sensitized EC/CUHK1(As-) cells to As 2O 3-induced apoptosis,and enhanced the efficacy of As 2O 3-induced apoptosis of EC/CUHK1 cells.Conclusion:Catalase reversed the effect of DMNQ on EC/CUHK1 and EC/CUHK1(As-) cells. It was concluded that the susceptibility of esophageal cells to arsenic trioxide-induced apoptosis is determined by ROS level in the cells.