Nawrocki-Raby Béatrice, Gilles Christine, Polette Myriam, Martinella-Catusse Corinne, Bonnet Noël, Puchelle Edith, Foidart Jean-Michel, Van Roy Frans, Birembaut Philippe
Institut National de la Santé et de la Recherche Mèdicale (INSERM) Unité Mixte de Recherche Santé (UMRS) 514, Laboratoire Pol Bouin, Reims, France.
Am J Pathol. 2003 Aug;163(2):653-61. doi: 10.1016/S0002-9440(10)63692-9.
The disorganization of E-cadherin/catenin complexes and the overexpression of matrix metalloproteinases (MMPs) are frequently involved in the capacity of epithelial cells to acquire an invasive phenotype. The functional link between E-cadherin and MMPs was studied by transfecting invasive bronchial BZR tumor cells with human E-cadherin cDNA. Using different in vitro (cell dispersion, modified Boyden chamber) and in vivo assays (human airway epithelial xenograft), we showed that E-cadherin-positive clones displayed a decrease of invasive abilities. As shown by immunoprecipitation, the re-expressed E-cadherin was able to sequestrate one part of free cytoplasmic beta-catenin in BZR cells. The decrease of beta-catenin transcriptional activity in E-cadherin-transfected clones was demonstrated using the TOP-FLASH reporter construct. Finally, we observed a decrease of MMP-1, MMP-3, MMP-9, and MT1-MMP, both at the mRNA and at the protein levels, in E-cadherin-positive clones whereas no changes in MMP-2, TIMP-1, or TIMP-2 were observed when compared with control clones. Moreover, zymography analysis revealed a loss of MMP-2 activation ability in E-cadherin-positive clones treated with the concanavalin A lectin. These data demonstrate a direct role of E-cadherin/catenin complex organization in the regulation of MMPs and suggest an implication of this regulation in the expression of an invasive phenotype by bronchial tumor cells.
E-钙黏蛋白/连环蛋白复合物的紊乱和基质金属蛋白酶（MMPs）的过表达常常与上皮细胞获得侵袭性表型的能力有关。通过用人E-钙黏蛋白cDNA转染侵袭性支气管BZR肿瘤细胞，研究了E-钙黏蛋白与MMPs之间的功能联系。使用不同的体外（细胞分散、改良的Boyden小室）和体内试验（人气道上皮异种移植），我们发现E-钙黏蛋白阳性克隆的侵袭能力下降。免疫沉淀显示，重新表达的E-钙黏蛋白能够在BZR细胞中隔离一部分游离的细胞质β-连环蛋白。使用TOP-FLASH报告构建体证明了E-钙黏蛋白转染克隆中β-连环蛋白转录活性的降低。最后，我们观察到E-钙黏蛋白阳性克隆中MMP-1、MMP-3、MMP-9和MT1-MMP在mRNA和蛋白质水平均下降，而与对照克隆相比，MMP-2、TIMP-1或TIMP-2没有变化。此外，酶谱分析显示，用伴刀豆球蛋白A凝集素处理的E-钙黏蛋白阳性克隆中MMP-2激活能力丧失。这些数据证明了E-钙黏蛋白/连环蛋白复合物组织在MMPs调节中的直接作用，并表明这种调节在支气管肿瘤细胞侵袭性表型的表达中起作用。
