miR-101对结直肠癌细胞放疗敏感性的影响及机制探讨  

Effect of miR-101 on radiosensitivity of colorectal cancer cells and its mechanism

作　　者：刘燕[1,2] 刘钧[1] 何欣蓉[1] 陈筱莉[1] 蹇顺海[1] 张超[2] 李学农[2] LIU Yan;LIU Jun;HE Xinrong;CHEN Xiaoli;JIAN Shunhai;ZHANG Chao;LI Xuenong(North Sichuan Medical College,Nanchong 637000,China)

机构地区：[1]川北医学院,四川南充637000 [2]南方医科大学

出　　处：《山东医药》2018年第18期1-4,共4页Shandong Medical Journal

基　　金：国家自然科学基金资助项目(81302158)

摘　　要：目的观察miR-101对结直肠癌细胞放疗敏感性的影响,并探讨其分子机制。方法取结直肠癌细胞株SW620、SW480,稳定过表达miR-101细胞株SW620(miR101-SW620)及其阴性对照GV209-SW620,瞬时沉默miR-101表达细胞株SW480(SW480-miR101)及其阴性对照SW480-NC,采用Western blotting法检测细胞中miR-101靶基因Ras相关的C3肉毒素底物1(Rac1)及其下游关键蛋白细胞分裂周期蛋白42(Cdc42)、人Ras同源基因家族成员A(Rho A)。取SW620、GV209-SW620、miR101-SW620细胞,分别给予0、2、4、6、8 Gy射线处理24 h;Western blotting法检测DNA损伤标志性蛋白γ-H2AX、细胞凋亡标志蛋白Caspase-3判断细胞放疗敏感性变化,同时检测细胞Rac1、Cdc42、Rho A蛋白。结果与SW620、GV209-SW620细胞比较,miR101-SW620细胞Rac1、Cdc42、Rho A蛋白表达降低(P均﹤0.05);与SW480、SW480-NC细胞比较,SW480-miR101细胞Rac1、Cdc42、Rho A蛋白表达均增高(P均﹤0.05)。随着照射剂量增加,结直肠癌细胞γ-H2AX、Caspase-3表达均增高,而Rac1、Rho A、Cdc42蛋白表达均降低(P均﹤0.05);与同等照射剂量下SW620、GV209-SW620细胞比较,miR101-SW620细胞γ-H2AX、Caspase-3蛋白表达均增高,而Rac1、Rho A、Cdc42蛋白表达均降低(P均﹤0.05)。结论 miR-101可能通过调控Rac1/Cdc42/Rho A信号通路增强结直肠癌细胞对放疗的敏感性。Objective To observe the effect of miR-101 on radiosensitivity of colorectal cancer cells,and to investigate its molecular mechanism. Methods We cultured colorectal cancer cell lines of SW620,SW480,negative control of SW620（ GV209-SW620）, SW620 with overexpression of miR-101（ miR101-SW620）, negative control of SW480（ SW480-NC）,and transiently silenced miR-101 on SW480 cells（ SW480-miR101）. The expression of Ras-related C3 botulinum toxin substrate 1（ Rac1）,cell division cycle protein 42（ Cdc42）,and ras homologous A（ Rho A） was detected by Western blotting. SW620,GV209-SW620,and miR101-SW620 cells were treated with 0,2,4,6,and 8 GY rays for24 h. We detected the expression of markers such as γ-H2 AX and Caspase-3,we also examined the expression of Rac1,Cdc42 and Rho A in each group. Results Compared with the SW620 and GV209-SW620 cells,the expression of Rac1,Cdc42 and Rho A in the miR101-SW620 cells decreased（ all P〈0. 05）. Compared with the SW480 and SW480-NC cells,the expression of Rac1,Cdc42 and Rho A in the SW480-miR101 cells increased（ all P〈0. 05）. With the increase of irradiation dose,the expression of γ-H2 AX and Caspase-3 in colorectal cancer cells increased,while the protein expression of Rac1,Rho A and Cdc42 decreased（ all P〈0. 05）. Compared with SW620 and GV209-SW620 cells at the same dose,the expression of γ-H2 AX and Caspase-3 protein increased in the SW620 cells,while the expression of Rac1,Rho A and Cdc42 protein decreased（ all P〈0. 05）. Conclusions The miR-101 may enhance the sensitivity of colorectal cancer cells to radiotherapy by modulating the Rac1/Cdc42/Rho A signaling pathway.

关 键 词：结直肠癌 放射治疗 微小核糖核酸-101 Ras相关的C3肉毒素底物1 细胞分裂周期蛋白42 人Ras同源基因家族成员A 

分 类 号：R735.3[医药卫生—肿瘤]