Ecadherinin

Ecadherinin, commonly known as E-cadherin, is a calcium-dependent cell–cell adhesion glycoprotein of the classical cadherin family. In humans, it is encoded by the CDH1 gene. E-cadherin is a single-pass transmembrane protein with an extracellular domain that mediates homophilic, calcium-dependent adhesion to E-cadherin on adjacent cells, forming adherens junctions essential for epithelial tissue integrity and polarity. Its cytoplasmic tail binds catenins, including beta-catenin and p120-catenin, linking the junction to the actin cytoskeleton via alpha-catenin and other actin-binding proteins.

Functionally, E-cadherin supports strong intercellular adhesion, helps maintain tissue architecture, and contributes to the regulation of cellular signaling. By sequestering beta-catenin at the membrane, it can modulate Wnt signaling and influence gene expression programs related to differentiation and proliferation. E-cadherin expression is tightly regulated at transcriptional and epigenetic levels and can be affected by post-translational processes such as proteolytic shedding and endocytosis, which alter junction stability.

Regulation and disruption of E-cadherin have significant clinical implications. Loss or reduction of E-cadherin function is associated with cancer progression and metastasis, particularly diffuse-type gastric cancer and invasive lobular carcinoma of the breast. Mechanisms include transcriptional repression by factors such as SNAI1, ZEB1, and SLUG, promoter hypermethylation, and somatic or germline mutations in CDH1. Germline CDH1 mutations predispose individuals to hereditary diffuse gastric cancer, illustrating the role of E-cadherin in tumor suppression and tissue organization.

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