摘要
目的探讨细胞周期蛋白酶抑制剂7(CDK7)THZ1对人胶质瘤细胞U251的体外放射增敏性。方法体外培养人胶质瘤细胞U251。MTT检测THZ1对U251的毒性作用,绘制不同浓度(0、8、16、32、64、128、256、512 noml/L)THZ1处理下的细胞存活曲线,并计算其IC50及IC20,将IC20作为后续试验的药物作用浓度。克隆形成实验检测射线联合THZ1对U251的作用,计算放射敏感性参数,绘制集落形成数量曲线。流式细胞术检测各组细胞周期分布。Westernblotting检测CDK7细胞周期蛋白、Bax凋亡相关蛋白及γH2AX蛋白表达。多组间比较采用单因素方差分析,两组间比较采用独立样本t检验,2因素组间对比采用析因设计方差分析。结果 THZ1对U251具有增殖抑制作用,且呈浓度和时间依赖性;单独应用THZ1可使CDK7细胞周期蛋白抑制,X射线(6 Gy)联合IC20浓度THZ1(10 nmol/L)能够降低U251的克隆能力,放射增敏比为1.478,同时可使G0/G1期细胞比例由67%减少到11%、G2/M期细胞比例由12%增加到70%;凋亡相关蛋白Bax表达增加,DNA双链断裂标志γH2AX蛋白表达增加。结论 THZ1对U251具有放射增敏作用,其可能的机制是THZ1联合射线降低细胞损伤修复能力,诱导细胞凋亡,调节凋亡相关蛋白的表达,改变细胞生长周期。
Objective To investigate the effects of cyclin-dependent kinase 7(CDK7) inhibitor, THZ1, on the radiosensitivity of human glioma cell line U251 in vitro. Methods U251 cells were cultured in vitro. The toxic effects of THZ1 on U251 cells was detected with MTT. The cell survival curves were drawn at different concentrations of THZ1(0, 8, 16, 32, 64, 128, 256, 512 noml/L). IC50 and IC20 were calculated and IC20 was used as the concentration for subsequent experiments. The effects of X-ray combined with THZ1 on U251 was detected with clone formation experiment. Radiosensitivity parameters were calculated and the curve of colony formation number was drawn. Cell cycle distribution in each treatment group was detected with flow cytometry. The expressions of CDK7 cyclin, Bax apoptosis-related proteins and γH2 AX were detected with Western blotting. One-factor analysis of variance was used for comparison among groups. Independent sample t test was used for comparison between groups. Factorial design analysis of variance was used for two-factor comparison among groups. Results THZ1 inhibited U251 proliferation in a concentration-and time-dependent manner. THZ1 inhibited CDK7 cyclin. X-ray(6 Gy) combined with IC20 concentration of THZ1(10 nmol/L) reduced the cloning ability of U251(the ratio of enhancing sensitivity being 1.478), decreased the percentage of G0/G1 phase from 67% to 11%, increased the percentage of G2/M phase from 12% to 70%, and increased the expressions of Bax apoptosis-related proteins and γH2 AX. Conclusion THZ1 can increase the radiosensitivity of U251. The possible mechanism is that THZ1 combined with X-ray inhibits the repair ability of cells, induces cell apoptosis, regulates expressions of apoptosis-related proteins, and intervenes in the cell cycle.
作者
李文清
叶兰
姜玉华
LI Wenqing;YE Lan;JIANG Yuhua(Cancer Prevention and Control Center,The Second Hospital of Shandong University,Jinan 250031,Shandong,China)
出处
《山东大学学报（医学版）》
CAS
北大核心
2021年第1期8-13,27,共7页
Journal of Shandong University:Health Sciences
基金
山东省自然科学基金(ZR2017MH027)
山东省重点研发计划(2019GSF108117)。
