替莫唑胺对人胶质瘤细胞系U251细胞miR125b的影响

目的探讨替莫唑胺(TMZ)对人胶质瘤细胞系U251细胞的miRNA125b的表达影响。方法将人胶质瘤细胞系U251细胞分成空白对照组、TMZ组,TMZ组设10、25、50、100、200、400、600μmol/L组。各组分别作用于24、48、72 h后进行实时定量PCR(Real-time PCR)检测miRNA-125b的表达水平;用MTT比色法检测细胞活力;流式细胞仪检测细胞周期和凋亡率。结果荧光定量PCR检测结果显示:替莫唑胺作用24 h后,miRNA125b表达变化不明显;48 h后对miR-125b表现出抑制作用,miR-125b对U251细胞的抑制率呈良好的时间-剂量效应关系,其Ic50为76μmol,初始抑制浓度为50μmol;流式细胞仪检测显示,U251细胞经TMZ作用后出现G2/M期阻滞,但促凋亡作用并不显著。结论在TMZ对胶质瘤细胞治疗过程中,hsa-miR-125b的表达随着治疗剂量而被抑制,miR-125b可以作为TMZ在用药过程中效果的检测以及抗药性反应的参考依据。

Temozolomide in glioblastoma cells U251 affect miR-125b expression

Objective To investigate the temozolomide（TMZ） affect on the expression of hsa-miR-125b human neureblastoma cell line U251 cells.Method U251 cells we treated 7 different concentrations of TMZ （10、25、50、100、200、400、600 μmol/L） 72 h, hsa-miR-125 expression level was identified by quantitve real time PCR （ qRT-PCR） .Cell viability was accessed by using colorimotrlc MTT assay Cell cycle progression and apoptosis ratio are measured by using flow cytometry .Results After TMZ affect 24h, the changes of miRNA-125b expression were unconspic-uous, and after 48h, the expression of miRNA-125b was inhibited.The IC50 of TMZ Was 76 mol/L.The relationship between the expression level of miR-125b and the inhibition rate of U251 cells was a perfect time to dose response . There were significant difference between the control group and the groups over 50 mol/L（P＆lt;0.01）. Flow cytometry showed that U251 cells responded to TMZ by undergoing G2/M arrest and very few cells show apoptosis.Conclusion TMZ inhibits the expression of has-miR-125b,expression of miRNA-125b may play a potential role in feedback effect of treatment ,and as the resistance reaction of reference .