上皮间质转化介导肿瘤转移的分子机制

The Molecular Mechanism of Epithelial-mesenchymal Transition Mediating Tumor Metastasis

上皮间质转化(epithelial-mesenchymal transition, EMT)是上皮细胞上皮样特征减少并获得间充质细胞特性的生理过程。EMT是肿瘤细胞侵袭转移所必要的初始步骤, EMT过程中上皮细胞失去细胞极性和细胞黏附能力,并获得迁移和侵袭性。在EMT过程中,肿瘤细胞频繁出现E-钙黏蛋白(E-cadherin)功能的丧失, N-钙黏蛋白(N-cadherin)、波形蛋白(vimentin)及基质金属蛋白酶(matrix metalloproteinases, MMPs)表达水平的上调,β-连环蛋白(β-catenin)从细胞膜到细胞核的重新定位。EMT相关转录因子Twist、Snail及Zeb家族的异常高表达均经促进EMT而介导肿瘤细胞的侵袭转移。

Epithelial-mesenchymal transition(EMT) is a process whereby epithelial cells lose many of their epithelial traits and acquire various features of mesenchymal cells. EMT is considered as an initial and necessary step by which epithelial cells lose their cell polarity and cell-cell adhesion, and gain migratory and invasive properties. Functional loss of E-cadherin, up-regulated expression of N-cadherin, vimentin and matrix metalloproteinases(MMPs) and reorientation of β-catenin from the cell membrane to the nucleus are frequently observed in the tumor cells undergoing EMT. All of the EMT-related transcription factor members in Twist, Snail and Zeb families mediate the invasion and metastasis of tumor cells by promoting EMT.