CDH1
CDH1 encodes E-cadherin, a classical cell-cell adhesion molecule essential for maintaining epithelial tissue architecture. It acts as a powerful tumor suppressor by physically restraining cells and sequestering beta-catenin; its loss is the defining event in the epithelial-mesenchymal transition (EMT) and metastasis.
Key Takeaways
- •CDH1 (E-cadherin) is the fundamental molecular glue that holds epithelial cells together into organized sheets.
- •It acts as a potent tumor suppressor by sequestering β-catenin at the membrane, inhibiting proliferative Wnt signaling.
- •Loss of E-cadherin is the hallmark defining event of the Epithelial-Mesenchymal Transition (EMT) and metastasis.
- •Germline mutations cause Hereditary Diffuse Gastric Cancer and severely increase the risk of lobular breast cancer.
Basic Information
- Gene Symbol
- CDH1
- Full Name
- Cadherin 1
- Also Known As
- E-cadherinUvomorulinCAM 120/80
- Location
- 16q22.1
- Protein Type
- Transmembrane Adhesion Receptor
- Protein Family
- Classical Cadherins
Related Isoforms
Expressed in neural and mesenchymal tissues; cells often switch from E- to N-cadherin during EMT.
Placental cadherin, also found in basal layers of stratified epithelia.
Key SNPs
A well-studied promoter variant (-160C>A) associated with reduced transcriptional activity and increased cancer risk.
Evaluated in cancer risk panels, frequently linked to gastric and prostate cancer susceptibility.
Overview
CDH1 encodes E-cadherin, a masterpiece of molecular engineering that physically zips epithelial cells together. Found at the adherens junctions of almost all epithelial tissues (like the lining of the gut, breast ducts, and skin), E-cadherin molecules reach out across the intercellular space to bind to identical E-cadherin molecules on neighboring cells. This homophilic binding strictly requires calcium ions, which act as a hinge to rigidify the extracellular domains.
However, E-cadherin is far more than just glue. Its intracellular tail is a powerful signaling hub. It binds a complex of catenins (p120, α, and β-catenin) that anchor the complex to the actin cytoskeleton, providing mechanical strength. Crucially, by trapping β-catenin at the cell membrane, E-cadherin prevents it from migrating to the nucleus and activating the Wnt proliferation pathway. Because it physically restrains cells and blocks Wnt signaling, CDH1 is a highly potent tumor suppressor gene.
Conceptual Model
A simplified mental model for the pathway:
Intentionally simplified; real signaling is shaped by feedback loops, tissue context, and timing.
Core Health Impacts
- • Barrier integrity: Maintains the structural integrity and barrier function of epithelial tissues.
- • Contact inhibition: Mediates contact inhibition, forcing densely packed cells to stop dividing.
- • Wnt suppression: Suppresses the Wnt/β-catenin proliferation pathway.
- • EMT defense: Prevents the Epithelial-Mesenchymal Transition (EMT) and metastasis.
- • Cancer protection: Protects against Hereditary Diffuse Gastric Cancer and lobular breast cancer.
Protein Domains
Extracellular (EC) Repeats
Five tandem repeat domains (EC1-EC5) that bind calcium. The outermost domain (EC1) mediates the homophilic "handshake" with E-cadherin on the adjacent cell.
Transmembrane Domain
A single alpha-helical pass through the lipid bilayer that anchors the receptor and transmits tension between the outside and inside of the cell.
Cytoplasmic Tail
A highly conserved intracellular domain that binds p120-catenin (for stability) and β-catenin (for Wnt sequestration and actin linkage).
Upstream Regulators
Calcium Ions (Ca2+) Activator
Binding of extracellular calcium to the cadherin repeats is absolutely required for E-cadherin to become rigid, dimerize, and bind to neighboring cells.
SNAI1 (Snail) & SNAI2 (Slug) Inhibitor
Master EMT transcription factors that directly bind the CDH1 promoter to strongly repress its transcription, initiating metastasis.
TWIST1 & ZEB1 Inhibitor
Additional EMT-inducing transcription factors that silence CDH1 expression in response to TGF-β and other microenvironmental signals.
DNA Methyltransferases (DNMTs) Inhibitor
Enzymes that frequently hypermethylate the CDH1 promoter in sporadic cancers, leading to profound epigenetic silencing of the gene.
Downstream Targets
β-catenin (CTNNB1) Inhibits
A dual-function protein. E-cadherin binds β-catenin at the membrane to form adherens junctions, thereby sequestering it and preventing it from entering the nucleus to drive Wnt target genes.
p120-catenin (CTNND1) Activates
Binds the juxtamembrane domain of E-cadherin, stabilizing the complex at the cell surface and preventing its endocytosis and degradation.
α-catenin (CTNNA1) Activates
Links the E-cadherin/β-catenin complex directly to the actin cytoskeleton, providing mechanical strength to the epithelial sheet.
EGFR & RTKs Inhibits
E-cadherin can physically associate with and restrict the mobility/activation of various receptor tyrosine kinases, dampening growth factor signaling.
Hippo Pathway (YAP/TAZ) Activates
High cell density and intact E-cadherin junctions activate the Hippo kinase cascade, sequestering YAP/TAZ in the cytoplasm to stop proliferation (contact inhibition).
Role in Aging
The gradual decline of E-cadherin expression and adherens junction stability is a hallmark of epithelial aging. This loss of barrier integrity and structural organization contributes directly to multiple age-related pathologies.
Barrier Dysfunction
In the aging gut and skin, reduced E-cadherin weakens tight and adherens junctions. This "leaky gut" allows pathogens and endotoxins into the bloodstream, driving systemic inflammaging.
Loss of Contact Inhibition
As E-cadherin levels drop with age (often due to cumulative epigenetic silencing), cells become less responsive to spatial constraints, increasing the risk of hyperplasia and tumor formation.
Wnt/β-catenin Hyperactivity
Fewer E-cadherin molecules at the membrane means more free β-catenin can enter the nucleus. In older tissues, this aberrant Wnt signaling can exhaust stem cell pools and drive oncogenesis.
Senescence and EMT
Senescent cells secrete inflammatory cytokines (the SASP) like TGF-β, which potently downregulates CDH1 in neighboring cells, initiating EMT and creating a pro-tumorigenic microenvironment.
Epigenetic Drift
The promoter region of CDH1 becomes progressively hypermethylated with advancing age in normal epithelia, creating a "field defect" that lowers the threshold for cancer initiation.
Wound Healing Impairment
Effective wound healing requires a coordinated, temporary downregulation of E-cadherin to allow cells to migrate over the wound bed. In aging, this dynamic regulation becomes rigid and dysfunctional.
Disorders & Diseases
Hereditary Diffuse Gastric Cancer (HDGC)
A highly penetrant autosomal dominant cancer syndrome caused by germline truncating mutations in CDH1. It carries an estimated 70% lifetime risk of diffuse gastric cancer.
Lobular Breast Carcinoma
Women with germline CDH1 mutations have a 40-50% lifetime risk of invasive lobular breast cancer. Even in sporadic cases, the complete loss of E-cadherin is the defining diagnostic hallmark of lobular (versus ductal) breast carcinoma. The cells grow in characteristic "Indian files" due to lack of adhesion.
Sporadic Carcinomas (EMT)
In almost all epithelial cancers (colon, lung, prostate), the somatic silencing of CDH1 (via methylation or Snail/Slug expression) is the critical trigger that allows the tumor to break through the basement membrane and metastasize.
Developmental Clefts
Rare specific germline missense mutations in CDH1 are associated with non-syndromic cleft lip and palate, highlighting E-cadherin’s role in the fusion of facial prominences during embryogenesis.
Interventions
Supplements
Known to upregulate E-cadherin expression and promote epithelial differentiation in various cell types, particularly in the colon.
A compound from broccoli sprouts reported to inhibit epigenetic silencing (HDACs/DNMTs) of CDH1, restoring its expression in cancer models.
Soy-derived isoflavone that has been shown to counteract EMT-inducing transcription factors like Snail, thereby preserving E-cadherin.
Lifestyle
Chronic inflammation drives cytokines (like TNF-α and TGF-β) that activate Snail/Slug to repress E-cadherin. Reducing systemic inflammation protects the epithelial barrier.
H. pylori infection or chronic alcohol/NSAID abuse damages the gastric mucosa, accelerating the loss of E-cadherin and promoting carcinogenesis.
The primary, life-saving clinical intervention for individuals carrying highly penetrant germline CDH1 mutations, due to the insidious nature of diffuse gastric cancer.
Medicines
Used to reverse the epigenetic hypermethylation of the CDH1 promoter, attempting to restore E-cadherin expression and revert cells to an epithelial state.
Cells that lose E-cadherin often become highly dependent on Focal Adhesion Kinase (FAK) for survival and motility; targeting FAK exploits this synthetic vulnerability.
Because E-cadherin loss frees β-catenin to drive proliferation, blocking downstream Wnt signaling is a major therapeutic goal in CDH1-deficient tumors.
Lab Tests & Biomarkers
Genetic Testing
Diagnostic test for Hereditary Diffuse Gastric Cancer (HDGC). A positive result usually prompts prophylactic total gastrectomy.
Research/diagnostic assays assessing the methylation status of the CDH1 promoter in tumor tissue, indicating epigenetic silencing.
Tissue Markers (IHC)
The gold standard pathological stain to differentiate lobular breast cancer (completely negative) from ductal breast cancer (strongly positive at the membrane).
When E-cadherin is lost, β-catenin staining often shifts from the membrane to the cytoplasm and nucleus, indicating active Wnt signaling.
Circulating Markers
The extracellular domain of E-cadherin can be cleaved by proteases (like ADAM10) and shed into the blood. Elevated serum levels are being evaluated as a biomarker for cancer progression and metastasis.
Hormonal Interactions
Estrogen Transcriptional Regulator
Often upregulates E-cadherin in breast and ovarian epithelia, promoting a differentiated, non-invasive phenotype.
Progesterone Epithelial Stabilizer
Works in concert with estrogen to maintain adherens junctions and the structural integrity of the endometrium.
Deep Dive
Network Diagrams
E-Cadherin Adherens Junction Assembly
CDH1 Loss Drives Wnt/β-catenin Signaling
Biochemical Mechanics: The Cadherin Zipper
The mechanical strength of the adherens junction is a masterpiece of dynamic structural biology. The extracellular portion of E-cadherin consists of five repeating domains (EC1-EC5).
The Calcium Hinge: Between each EC domain is a hinge region. Calcium ions bind to these hinges. Without calcium, the protein is floppy and inactive. With calcium, the receptor becomes a rigid rod, capable of extending away from the cell surface.
Homophilic Binding: The very tip of the molecule (the EC1 domain) contains a conserved tryptophan residue (Trp2). In a process called strand-swapping, the Trp2 of an E-cadherin molecule on Cell A inserts into a hydrophobic pocket on the EC1 domain of an E-cadherin molecule on Cell B. This creates an immensely strong, specific lock.
Cytoskeletal Tension: For the junction to be stable, the intracellular tail of E-cadherin must bind β-catenin and α-catenin, which link it to the actin cytoskeleton. When adjacent cells pull against each other, α-catenin changes conformation, recruiting more actin and reinforcing the junction under tension.
Epithelial-Mesenchymal Transition (EMT)
EMT is an ancient developmental program used during embryogenesis (e.g., neural crest cell migration). Cancers hijack this program to metastasize, and the loss of CDH1 is the defining molecular event.
The Trigger: Tumor microenvironment signals, especially TGF-β from immune cells or hypoxia, activate master EMT transcription factors: Snail, Slug, Twist, and ZEB1.
Repression: Snail binds directly to E-boxes in the CDH1 promoter, recruiting histone deacetylases (HDACs) and DNA methyltransferases to definitively shut off CDH1 transcription.
The Cadherin Switch: As E-cadherin is lost, the cells upregulate N-cadherin (Neural cadherin) or Vimentin. N-cadherin binds weakly to stromal cells and fibroblasts, allowing the tumor cell to detach from its neighbors, change shape, and invade the surrounding tissue and blood vessels.
The β-catenin Sequestration Trap
The most profound signaling role of E-cadherin is its regulation of the Wnt pathway. This is a story of physical sequestration.
The Balancing Act: β-catenin has two jobs. If it’s at the membrane, it’s a structural glue. If it’s in the nucleus, it’s a powerful growth-inducing transcription factor. A normal cell produces a steady stream of β-catenin.
The Membrane Sink: E-cadherin has an extremely high affinity for β-catenin. In a healthy, densely packed epithelial tissue, vast arrays of E-cadherin trap almost all available β-catenin at the membrane. Any excess β-catenin in the cytoplasm is rapidly degraded by the APC destruction complex.
The Release: When E-cadherin is mutated (as in HDGC) or transcriptionally silenced (during EMT), the membrane “sink” vanishes. A massive flood of β-catenin is released into the cytoplasm. It overwhelms the APC destruction complex, enters the nucleus, binds TCF/LEF, and drives the explosive transcription of MYC and Cyclin D1, fueling unchecked proliferation.
Relevant Research Papers
Links go to PubMed (abstracts are public); some papers also offer free full text via PMC or the publisher.
The landmark study establishing CDH1 germline mutations as the cause of Hereditary Diffuse Gastric Cancer (HDGC).
A nuanced study showing that while CDH1 loss initiates EMT, some invasive breast cancers surprisingly require E-cadherin for survival during systemic metastasis.
One of the first major papers demonstrating that CDH1 is frequently inactivated by epigenetic silencing in sporadic cancers.
Comprehensive review detailing the dual role of the E-cadherin/catenin complex in cell adhesion and Wnt signaling.
The pivotal discovery that the transcription factor Snail directly binds the CDH1 promoter to trigger the epithelial-mesenchymal transition.
Details the specific pathology of invasive lobular breast carcinoma, a disease defined entirely by the biallelic loss of CDH1.