The apical junctional complex (AJC) is a cell-cell adhesion system present at the upper portion of the lateral membrane of epithelial cells integrated by the tight junction (TJ) and the adherens junction (AJ). This complex is crucial to initiate and stabilize cell-cell adhesion, to regulate the paracellular transit of ions and molecules and to maintain cell polarity. Moreover, we now consider the AJC as a hub of signal transduction that regulates cell-cell adhesion, gene transcription and cell proliferation and differentiation. The molecular components of the AJC are multiple and diverse and depending on the cellular context some of the proteins in this complex act as tumor suppressors or as promoters of cell transformation, migration and metastasis outgrowth. Here, we describe these new roles played by TJ and AJ proteins and their potential use in cancer diagnostics and as targets for therapeutic intervention.

中文翻译：

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顶端连接蛋白，基因表达与癌症之间的关系。

根尖连接复合体（AJC）是一种细胞-细胞粘附系统，存在于上皮细胞外侧膜的上部，由紧密连接（TJ）和粘附连接（AJ）整合在一起。该复合物对于启动和稳定细胞间粘附，调节离子和分子的旁细胞转运以及维持细胞极性至关重要。此外，我们现在将AJC视为调节细胞与细胞粘附，基因转录以及细胞增殖和分化的信号转导枢纽。AJC的分子成分是多种多样的，根据细胞情况，该复合物中的某些蛋白质可作为肿瘤抑制因子或细胞转化，迁移和转移产物的启动子。这里，