埃兹蛋白477位酪氨酸的磷酸化在神经生长因子前体促进乳腺癌细胞侵袭中起关键作用  

Phosphorylation of ezrin Tyr477 is critical in invasion of breast cancer cells stimulated by precursor of nerve growth factor

作　　者：李福喜[1] 邵文凤[1] 唐芮[1] 于晓然[1] 温桥生 余焱林 熊静波[1] 

机构地区：[1]南方医科大学基础医学院细胞生物学教研室,广东广州510515 [2]国立癌症研究所肿瘤生物与遗传实验室,国立卫生研究院,美国马里兰州贝塞斯达市

出　　处：《南方医科大学学报》2016年第7期898-903,共6页Journal of Southern Medical University

基　　金：国家自然科学基金(81071810;81172058)~~

摘　　要：目的研究神经生长因子前体(precursor of nerve growth factor,pro NGF)促进乳腺癌细胞侵袭的作用与埃兹蛋白(ezrin)表达水平及其567位苏氨酸(Thr567)和477位酪氨酸(Tyr477)的磷酸化的相互关系。方法用梯度浓度的pro NGF(0、2.5、5和10 ng/m L)刺激人乳腺癌细胞系MDA-MB-231和MCF-7,用Transwell侵袭实验检测pro NGF对MDA-MB-231和MCF-7侵袭的影响;用免疫印迹法检测ezrin蛋白的表达水平,ezrin Thr567和ezrin Tyr477磷酸化水平的变化;在MDA-MB-231中转染p Enter-His-ezrin Y477F质粒(ezrin显性负突变质粒),研究ezrin Tyr477磷酸化在pro NGF促进乳腺癌细胞侵袭中的作用。结果pro NGF以浓度依赖的方式促进MDA-MB-231和MCF-7的侵袭(P<0.05);pro NGF以浓度依赖和时间依赖的方式显著升高ezrin Tyr477磷酸化,而对ezrin蛋白的表达以及其Thr567磷酸化无明显影响;Src激酶特异抑制剂SKI-606显著抑制pro NGF对ezrin Tyr477磷酸化的促进作用;转染p Enter-His-ezrin Y477F抑制pro NGF对MDA-MB-231细胞ezrin Tyr477磷酸化和侵袭能力的促进作用(P<0.05)。结论 ezrin Tyr477磷酸化在pro NGF促进乳腺癌细胞侵袭中起关键作用;pro NGF通过激活Src激酶使ezrin Tyr477发生磷酸化。Objective To investigate the effect of precursor of nerve growth factor（pro NGF） in promoting invasion of breast cancer cells and its relation with ezrin expression and phosphorylation of ezrin Thr567 and Tyr477.Methods Human breast cancer cell lines MDA-MB-231 and MCF-7 were stimulated by gradient concentrations of pro NGF（0,2.5,5 and 10 ng/m L） for16 h,and the invasion of the cells was assessed with Transwell assay.The expression of ezrin and the phosphorylation of ezrin Thr567 and ezrin Tyr477 in the treated cells were examined by Western blotting.MDA-MB-231 cells were transfected with p Enter-His-ezrin Y477F（a dominant negative mutant） to study the role of phosphrylation of ezrin Tyr477 in the invasion of breast cancer cell stimulated by pro NGF.Results pro NGF significantly promoted MDA-MB-231 and MCF-7 cell invasion in a concentration-dependent manner（P〈0.05）,and concentration-and time-dependently increased the phosphorylation of ezrin Tyr477（P〈0.05） without affecting the expression of ezrin or the phosphorylation of ezrin Thr567.The specific inhibitor of src,SKI-606,significantly inhibited the phosphorylation of ezrin Tyr477 induced by pro NGF.Transfection with p Enter-Hisezrin Y477 F inhibited pro NGF-induced invasion and phosphorylation of ezrin Tyr477 in MDA-MB-231 cells（P〈0.05）.Conclusion Phosphorylation of ezrin Tyr477 plays a critical role in the invasion of breast cancer cells stimulated by pro NGF via pro NGF/src/ezrin Tyr477 pathway.

关 键 词：乳腺癌 神经生长因子前体 埃兹蛋白 侵袭 

分 类 号：R737.9[医药卫生—肿瘤]