摘要
To explore the association of in herent cellular reactive oxygen species (ROS) levels with susceptibility of the tumor cells to apoptosis induction by arsenic trioxide (As 2O 3) Methods Low concentration (2?μmol/L) of As 2O 3 was administered to two cultured leukemic cell lines, NB4 and U937, and two esophageal carcinoma cell lines, EC1 71 (also named EC/CUHK1) and EC1867, to confirm the difference in apoptosis su sceptibility of NB4 versus U937 and of EC1 71 versus EC1867 Dihydro genrhodamine 123 (DHR123), used as a ROS capture agent, was incubated with cell s in the absence of As 2O 3 Fluorescence intensity of rhodamine 123, the pro duct of cellular oxidation of DHR123, was detected by flow cytometry and ROS was measured Results Low concentration of As 2O 3 induced apoptosis was more likely to occur in NB 4 and EC1 71 cells than in U937 and EC1867 cells, or NB4 was more sensitive tha n U937, and EC1 71 more sensitive than EC1867 to As 2O 3 The inherent cellu lar ROS level is higher in NB4 than in U937, and also higher in EC1 71 than in EC1867 Conclusions The difference in cellular ROS level is positively associated with cellular susc eptibility to apoptotis induction by As 2O 3 The inherent ROS level might be important in defining apoptotic susceptibility to As 2O 3
目的 探讨肿瘤细胞株的固有活性氧 (reactiveoxygenspecies,ROS)水平与细胞对三氧化二砷 (As2 O3)促凋亡的易感性之间的关系。方法 用小剂量 (2 μmol/L)As2 O3作用于人白血病细胞和食管癌细胞各一对 (NB4 /U937和EC1 71/EC186 7) ,以证实砷剂促凋亡敏感性在NB4和U937之间的差异以及在EC1 71和EC186 7之间的差异。然后在不加砷剂情况下 ,用活性氧捕获剂双氢罗丹明 12 3(DHR12 3)孵育细胞 (DHR12 3在细胞内被ROS氧化为发出荧光的罗丹明 12 3,Rh12 3) ,通过流式细胞仪检测细胞内Rh12 3的荧光而测得细胞内固有ROS水平。结果 As2 O3(2 μmol/L)在NB4和EC1 71造成明显凋亡 ,而在U937和EC186 7未造成明显凋亡。对砷剂敏感的NB4细胞的固有活性氧水平比砷剂不敏感的U937细胞高 ,对砷剂敏感的EC1 71细胞的固有活性氧水平比砷剂不敏感的EC186 7细胞高。结论 细胞固有ROS水平的差异与细胞对三氧化二砷诱导凋亡的易感性差异有关。
基金
grantsfromtheNationalNaturalScienceFoundationofChina (No . 3 973 0 2 70 )
ShanghaiEducationCommittee (No .2 0 0 0B10 1)
