摘要
目的研究microRNA-451在结直肠癌组织与细胞中的表达及其在MDR1/P-gp途径介导的多药耐药中的作用。方法收集68例新鲜结直肠癌及癌旁组织,RT-q PCR检测其miR-451表达情况,Western blot检测P-gp蛋白是否表达,并分析其关系;RT-q PCR检测结直肠癌耐奥沙利铂细胞HCT116/L、耐阿霉素细胞Lo Vo/adr及对应亲本细胞中miR-451的表达;利用脂质体将miR-451 mimics(模拟物)、NC RNAs转染2组耐药细胞,RT-q PCR和Western blot分别检测转染后其MDR1 mRNA和P-gp的表达;MTT检测转染细胞在不同浓度奥沙利铂、阿霉素下的增殖并计算其半数抑制浓度(IC50);流式细胞术进一步比较NC转染组和mimics转染组耐药细胞在同一浓度奥沙利铂、阿霉素下凋亡率。结果相对于癌旁组织,miR-451在结直肠癌组织中低表达,其表达下调与P-gp阳性表达存在相关性(r=-0.404,P=0.002);与亲本细胞相比,miR-451在2组耐药细胞中表达明显降低(P<0.01);mimics转染组细胞MDR1 mRNA、P-gp相对表达量明显下降,IC50及凋亡率与NC组均有显著差异(P<0.05)。结论 miR-451在结直肠癌中通过MDR1/P-gp途径参与多药耐药,耐药细胞转染miR-451mimics后,可部分逆转耐药。
Objective To investigate the expression of microRNA-451 in colorectal cancer（ CRC）tissue and cell lines,and explore its role in multidrug resistance mediated by multidrug resistance gene 1（ MDR1） /P-glycoprotein（ P-gp） pathway. Methods The expression of microRNA-451 and P-gp in 68 cases of CRC and matched non-tumor adjacent tissues was detected by RT-q PCR and Western blotting,and the correlation was analyzed. The expression of microRNA-451 in CRC cells（ HCT116 and Lo Vo） and corresponding drug-resistant cells [HCT116 / oxaliplation（ L-OHP） and Lo Vo / adriamycin（ Adr） ] was detected by RT-q PCR. The drug-resistant cells were transfected with microRNA-451 mimics and NC RNAs using Lipofectamine 2000,and then the expression of MDR1 and P-gp was measured by RT-q PCR and Western blotting. The proliferation of the transfected resistant cells treated with different concentrations of L-OHP or Adr was detected by MTT assay,and the IC50 values were calculated. Flow cytometry was used to analyze the apoptotic rate of the transfected resistant cells treated with the same concentration of L-OHP or Adr. Results Compared with the non-tumor adjacent tissues,microRNA-451 exhibited lower expression level in CRC tissues,and its down-regulation was associated with P-gp positive expression（ r =- 0. 404,P =0. 002）. The microRNA-451 levels were significantly lower in HCT-116 / L-OHP cells and Lo Vo / Adr cells than in their parental cells（ P〈0. 01）. The expression of MDR1 mRNA and P-gp was decreased in the microRNA-451 mimic transfection group as compared with the NC RNA transfection group,moreover,the IC50 and apoptotic rate had significant differences between the 2 groups（ P〈0. 05）. Conclusion MicroRNA-451 contributes to multidrug resistance through modulating the expression of MDR1 / P-gp in colorectal carcinoma,and its overexpression can partly reverse the multidrug resistance.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2016年第2期155-160,共6页
Journal of Third Military Medical University
基金
重庆市卫生局医学科研项目(2012-2-171)
