摘要目的 探讨miRNA-135b在多种乳腺癌细胞系中表达及靶向APC基因对三阴型乳腺癌细胞增殖、侵袭及迁移能力的影响.方法 通过实时荧光定量(RT)-聚合酶链反应(PCR)检测miRNA-135b在正常乳腺细胞系Hs578Bst及乳腺癌细胞系Hs578T、MCF7、HCC1937、MDA-MB-231、MDA-MB-453、BT-549和MDA-MB-468中的表达,选取其中两种高表达miRNA-135b的MDA-MB-231、MDA-MB-468为对象,根据处理方法,实验分3组:空白组(自然生长细胞)、阴性对照组(转染阴性对照试剂)、实验组(转染miRNA-135b抑制剂).采用RT-PCR及Western印迹检测APC基因的表达;Cell Counting Kit-8 (CCK-8)实验、Transwell体外侵袭实验检测乳腺癌细胞增殖、侵袭及迁移能力.结果 miRNA-135b在三阴型乳腺癌细胞系中的表达量均高,其中在MDA-MB-231细胞中阴性对照组和实验组分别0.97 ±0.13、0.42 ±0.03;MDA-MB-468细胞转染miRNA-135b抑制剂后,1.02±0.03、0.47±0.04;实验组中miRNA-135b的表达受到显著抑制,差异有统计学意义.实验组APC基因mRNA及其蛋白的表达显著上调,MDA-MB-231中阴性对照组和实验组分别为1.01±0.11、1.75±0.13(P=0.013,P=0.021),MDA-MB-468中(P=0.017,P=0.014);实验组细胞增殖活性明显受到抑制MDA-MB-231中(P=0.00),MDA-MB-468中(P=0.01);侵袭及迁移能力明显降低MDA-MB-231中(P=0.002,P=0.00),MDA-MB-468中(P=0.01,P=0.00).结论 miRNA-135b在多种三阴型乳腺癌细胞中呈高表达,可靶向抑制APC基因,促进三阴型乳腺癌细胞系MDA-MB-231及MDA-MB-468的增殖、侵袭及迁移.

abstractsObjective To explore the expression of miRNA-135b in a variety of breast cancer cell lines and its function on the proliferation,invasion and migration in triple-negative breast cancer cell lines by targeting adenomatous polyposis coli (APC).Methods Quantitative real-time (RT)-PCR was used to detect the expression of miRNA-135b in seven breast cancer cell lines and one normal breast cell line.The three-negative breast cancer cell lines MDA-MB-23 1 and MDA-MB-468 with miRNA-135b high-expression were divided into three groups:the normal growth group,the negative control group (transfected with negative counter-part) and the experimental group (transfected with miRNA-135b inhibitors).RT-PCR and Western blot were used to explore the expression of APC.The proliferation was detected by Cell Counting Kit-8 (CCK-8) method and the invasion and migration were detected by Transwell method.Results The levels of miRNA-135b were higher in triple-negative breast cancer cell lines than other types,especially MDA-MB-231 (P =0.001) and MDA-MB-468 (P =0.036).Compared with normal growth group and negative control group,the mRNA and protein of APC were up-regulated in experimental group MDA-MB-231(P =0.013,P =0.021),MDA-MB-468 (P =0.017,P =0.014).CCK-8 results showed that the proliferation rate of experimental group was decreased compared with negative control and nornal growth group MDA-MB-231 (P =0.00),MDA-MB-468 (P =0.01).The invasion and migration ability of MDAMB-231 (P =0.002,P =0.00) and MDA-MB-468 (P =0.01,P =0.00) were obviously decreased after transfected miRNA-135b inhibitors.Conehsion The expressions of miRNA-135b were higher in most triple-negative breast cancer cell lines than others,miRNA-135b could promote the proliferation,invasion and migration in triple-negative breast cancer cell lines MDA-MB-231 and MDA-MB-468,and APC was one of the target genes of miRNA-135b by participating in the process of regulation.