中文摘要：

目的：探讨MiRNA-122对肝癌耐药细胞株BEL-7402/氟尿嘧啶（fluorouracil,FU）的FU敏感性的影响及其作用机制。方法：构建miR-122及其阴性对照空载体并稳定转染至BEL-7402/FU细胞中,Western免疫印迹检测miR-122转染组（n=3）、阴性空载体转染组（n=3）和未转染组（n=3）中与耐药相关的Bcl-2和Bcl-XL蛋白表达水平。用3-（4,5-二甲基-2-噻唑）-2,5-二苯基溴化四氮唑噻唑[3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazoliumbromide,MTT）]法检测三组细胞对FU敏感性。结果：与未转染组、阴性空载体转染组比较,miR-122转染组Bcl-2和Bcl-XL蛋白表达明显降低（PP结论：miR-122能特异性地下调Bcl-2和Bcl-XL表达,可增加BEL-7402/FU细胞对FU敏感性。

英文摘要：

Objective： To investigate the effect of miR-122 on sensitivity to fluorouracil （FU） in transfected BEL-7402/ FU cells. Methods： MiR-122 and negative empty expression vectors were constructed and stably transfected into BEL-7402/FU cells. Western blot was used to detect Bcl-2 and Bcl-XL protein expression in the miR-122 transfectant group（n=3）, the negative empty vector transfectant group （n=3） and an untreated cell group（n=3）. Drug sensitivity of the cells to FU was analyzed with 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay. Results： Compared with the negative empty vector transfectant group and the untreated cells group, the protein expression levels of Bcl-2, Bcl-XL in the stable miR-122 transfectant group were decreased （PPConclusion： MiR-122 can specifically down-regulate the expression of Bcl-2 and Bcl-XL in BEL-7402/FU cells, which, in turn, increases spontaneous apoptosis and sensitivity to FU.