E-cadherin inhibits cell surface localization of the pro-migratory 5T4 oncofetal antigen in mouse embryonic stem cells
E-cadherin inhibits cell surface localization of the pro-migratory 5T4 oncofetal antigen in mouse embryonic stem cells
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DOI：
10.1091/mbc.e06-09-0875
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发表时间：
2007-08-01
影响因子：
3.3
通讯作者：
Ward, Christopher M.
中科院分区：
文献类型：
--
作者：
Spencer, Helen L.;Eastham, Angela M.;Ward, Christopher M.
上皮-间质转化（EMT）事件发生在胚胎发育过程中，对上皮肿瘤的转移扩散很重要。我们发现小鼠胚胎干细胞（ES）的自发分化与E-到N-钙粘蛋白的转换、E-钙粘蛋白阻遏分子（Snail和Slug蛋白）的上调、明胶酶活性（基质金属蛋白酶[MMP]-2和-9）和细胞运动性增加有关，这些都是EMT的特征性事件。5 T4癌胚抗原，以前被证明与非常早期的ES细胞分化和改变运动性，也是这个协调过程的一部分。E-和N-钙粘蛋白和5 T4蛋白在ES细胞分化过程中独立调节，并且不需要诱导EMT相关的转录物和蛋白质，如从各自的敲除ES细胞的研究中判断的。此外，使用中和抗体消除未分化ES细胞中E-钙粘蛋白介导的细胞-细胞接触导致可逆的间充质表型和肌动蛋白细胞骨架重排，其伴随着5 T4抗原以能量依赖性方式从细胞质易位至细胞表面。E-钙粘蛋白空ES细胞是组成型细胞表面5 T4阳性的，并且尽管在这些细胞中E-钙粘蛋白cDNA的强制表达足以恢复细胞-细胞接触，但5 T4抗原的细胞表面表达不变。5 T4和N-钙粘蛋白敲除ES细胞在EMT期间表现出显著降低的运动性，证明了这些蛋白在该过程中的功能作用。我们的结论是，E-钙粘蛋白蛋白稳定皮质肌动蛋白细胞骨架的安排在ES细胞，这可以防止细胞表面定位的promigrating 5 T4抗原。
Epithelial-mesenchymal transition (EMT) events occur during embryonic development and are important for the metastatic spread of epithelial tumors. We show here that spontaneous differentiation of mouse embryonic stem (ES) cells is associated with an E- to N-cadherin switch, up-regulation of E-cadherin repressor molecules (Snail and Slug proteins), gelatinase activity (matrix metalloproteinase [MMP]-2 and -9), and increased cellular motility, all characteristic EMT events. The 5T4 oncofetal antigen, previously shown to be associated with very early ES cell differentiation and altered motility, is also a part of this coordinated process. E- and N-cadherin and 5T4 proteins are independently regulated during ES cell differentiation and are not required for induction of EMT-associated transcripts and proteins, as judged from the study of the respective knockout ES cells. Further, abrogation of E-cadherin-mediated cell- cell contact in undifferentiated ES cells using neutralizing antibody results in a reversible mesenchymal phenotype and actin cytoskeleton rearrangement that is concomitant with translocation of the 5T4 antigen from the cytoplasm to the cell surface in an energy-dependent manner. E-cadherin null ES cells are constitutively cell surface 5T4 positive, and although forced expression of E-cadherin cDNA in these cells is sufficient to restore cell-cell contact, cell surface expression of 5T4 antigen is unchanged. 5T4 and N-cadherin knockout ES cells exhibit significantly decreased motility during EMT, demonstrating a functional role for these proteins in this process. We conclude that E-cadherin protein stabilizes cortical actin cytoskeletal arrangement in ES cells, and this can prevent cell surface localization of the promigratory 5T4 antigen.