Wnt2B通过NF-κB/p65调节乳腺癌细胞的凋亡  

Wnt2B-induced Apoptosis in Breast Cancer Cells Mediated by NF-κB/p65 in vitro

作　　者：王鸿雁[1] 范良生[1] 黄浩 周文娟[1] 宋欧诣[1] 马丁[1] 王常玉[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院妇产科,武汉430030 [2]湖北省老河口市人民医院妇产科,老河口441800

出　　处：《华中科技大学学报（医学版）》2012年第4期409-414,422,共7页Acta Medicinae Universitatis Scientiae et Technologiae Huazhong

基　　金：国家"973"重点基础科学研究基金资助项目(No.2009CB521808);国家自然科学基金资助项目(No.30901587;No.30700895;No.30973205)

摘　　要：目的研究Wnt2B对乳腺癌细胞株MDA-MB-231凋亡的影响,探讨其在乳腺癌发生发展过程中的重要作用。方法应用免疫组化技术检测40例乳腺癌组织标本中Wnt2B的表达;应用Western blot检测乳腺癌配对细胞系MDA-MB-231和MCF-7中Wnt2B蛋白水平;通过瞬时转染Wnt2B特异的siRNA沉默高表达Wnt2B的MDA-MB-231细胞系后,采用流式细胞仪检测转染前后细胞的凋亡水平;应用Western blot、共聚焦显微镜和凝胶电泳迁移实验(EM-SA)检测下调Wnt2B表达后对NF-κB/p65的表达和活性的影响。结果相对于Wnt2B阴性表达的正常乳腺组织,35例乳腺癌组织的表达呈强阳性并且存在核浆转移现象;在高转移细胞系MDA-MB-231中Wnt2B表达明显高于低转移细胞系MCF-7;针对Wnt2B的siRNA沉默成功下调MDA-MB-231中Wnt2B表达后,细胞凋亡率明显增加并伴随NF-κB/p65的表达下降和活性降低;应用NF-κB/p65特异性的抑制剂PDTC阻断此通路后,Wnt2BsiRNA诱导细胞的凋亡效应被阻断。结论 Wnt2BsiRNA通过NF-κB/p65通路抑制乳腺癌细胞系MDA-MB-231的凋亡而产生抗瘤作用,Wnt2B可能成为乳腺癌有效治疗靶点之一。Objective To investigate the effects of Wnt2B protein on apoptosis of breast cancer cell line MDA-MB-231 and its role in the pathogenesis of breast cancer.Methods Matched normal/tumor immunochemistry analysis was used to reveal the Wnt2B protein expression in breast cancer tissues and normal breast tissues.Wnt2B expression in two breast cancer cell lines（MDA-MB-231 and MCF7）was evaluated by Western blot.After transfection of siRNA targeting Wnt2B to silence the high expression of Wnt2B in MDA-MB-231 cells,the apoptosis was assayed by flow cytometry.By using Western blot,confocal microscopy and electrophoretic mobility shift assay（EMSA）,the effects of down-regulated Wnt2B expression on the expression and activity of nuclear factor kappa B subunit p65（NF-κB/p65）were tested.Results Wnt2B protein was significantly up-regulated in 35 out of 40 cases of breast cancer and translocation from cytoplasm to nuclear in metastasis cancer was observed.Highly metastatic breast cancer cells MDA-MB-231 had higher Wnt2B protein expression level than poorly metastatic breast cancer cells MCF-7.Cell apoptosis was enhanced and NF-κB/p65 was inactivated after Wnt2B siRNA transfection.The administration of PDTC（100 μmol/L）hindered silencing Wnt2B-induced cell apoptosis.Conclusion These findings proved that Wnt2B can regulate apoptosis of breast cancer cells through NF-κB/p65 pathway,and suggested that Wnt2B may exhibit its oncogenic potential in breast cancer through anti-apoptosis.

关 键 词：Wnt2B NF-ΚB P65 乳腺癌 细胞凋亡 

分 类 号：R735.9[医药卫生—肿瘤]