CDH1 Human, HEK

What is the CDH1 gene and what protein does it encode?

The CDH1 gene encodes E-cadherin, a calcium-dependent cell adhesion protein critical for maintaining epithelial tissue integrity. E-cadherin functions as a tumor suppressor by inhibiting cell invasion and metastasis. Mutations in this gene are associated with several cancer types, most notably hereditary diffuse gastric cancer (HDGC) and lobular breast cancer. The protein plays essential roles in cell-cell adhesion, epithelial morphogenesis, and signal transduction pathways including WNT/β-catenin signaling .

What are the primary cancer risks associated with CDH1 mutations?

CDH1 mutations significantly elevate cancer risks across multiple tissue types. For individuals with pathogenic CDH1 variants and a family history of related cancers, lifetime risk estimates are as follows:

• Hereditary diffuse gastric cancer: 70% for men and 56% for women

• Lobular breast cancer: 42% for women

• Brain tumors: Emerging evidence shows a 4.4% prevalence in CDH1 mutation carriers versus 0.2% in the general population

How do different CDH1 variants impact disease manifestation?

The functional consequences of CDH1 variants are heterogeneous. Recent research has identified specific variants with distinct molecular impacts:

• Ectodomain variants (e.g., p.A592T) demonstrate increased intramolecular flexibility

• Intracellular variants (e.g., p.A817V) show reduced β-catenin binding, resulting in elevated cytosolic and nuclear β-catenin levels

• Variant effects include altered membrane expression, disrupted cell migration, and abnormal cellular aggregation patterns

What cellular models are most appropriate for studying CDH1 function?

When selecting cellular models for CDH1 research, consider both epithelial and neural cell types depending on the research question. For studying gastric cancer mechanisms, gastric epithelial cell lines with intact cell-cell adhesion machinery provide relevant contexts. Recent findings demonstrate CDH1 expression in oligodendroglial cells isolated from rat brain, suggesting additional research applications in neural models . Cell models should be selected based on endogenous E-cadherin expression levels and the specific pathway interactions under investigation.

What gene editing approaches are effective for studying CDH1 variants?

CRISPR/Cas9-mediated knock-in techniques have proven highly effective for studying CDH1 variants. This approach allows precise modeling of specific variants such as p.A592T or p.A817V to assess their functional impacts. When designing CRISPR experiments:

• Incorporate appropriate controls including wild-type CDH1 and empty vector

• Consider both heterozygous and homozygous models to assess gene dosage effects

• Validate genetic modifications through sequencing

• Confirm variant expression through protein detection methods

What assays are most informative for characterizing CDH1 variant functions?

Multiple complementary assays should be employed to comprehensively assess CDH1 variant effects:

• Cell membrane expression analysis through immunofluorescence and surface biotinylation

• Cell migration assays (wound healing, transwell migration)

• Cell aggregation studies to assess adhesion properties

• Protein-protein interaction assays, particularly for β-catenin binding

• Subcellular fractionation to quantify β-catenin distribution between cytosolic and nuclear compartments

How does E-cadherin interact with the WNT/β-catenin signaling pathway?

E-cadherin functions as a critical regulator of WNT/β-catenin signaling through direct sequestration of β-catenin at the cell membrane. CDH1 variants that affect the intracellular domain (like p.A817V) can disrupt this interaction, leading to:

• Reduced β-catenin binding at the cell membrane

• Increased cytosolic and nuclear β-catenin levels

• Enhanced WNT/β-catenin signaling activity

• Potential activation of downstream transcriptional targets

These effects can be experimentally reversed using specific inhibitors such as the MAPK interacting serine/threonine kinase 1 inhibitor CGP 57380, providing insights into potential therapeutic targets .

What structural and molecular dynamics should be considered when studying CDH1 variants?

Molecular dynamics simulation models reveal critical insights into how CDH1 variants alter protein behavior. The p.A592T variant in the ectodomain demonstrates increased intramolecular flexibility, potentially disrupting adhesive functions. When designing studies examining structural consequences of variants:

• Compare wild-type and variant protein structures through computational modeling

• Assess protein stability and folding characteristics

• Evaluate impacts on calcium-binding domains

• Quantify changes in protein-protein interaction interfaces

• Consider both static structural changes and dynamic conformational behaviors

How do CDH1 mutations influence cellular phenotypes beyond adhesion?

Beyond direct adhesion effects, CDH1 mutations impact multiple cellular processes:

• Epithelial-to-mesenchymal transition (EMT) regulation

• Cell polarity establishment and maintenance

• Cytoskeletal organization and dynamics

• Receptor tyrosine kinase signaling

• Cell cycle progression and apoptosis sensitivity

Research designs should incorporate assays that capture these diverse cellular phenotypes to fully characterize variant effects.

What controls are essential when conducting CDH1 functional studies?

Robust experimental design for CDH1 research requires multiple controls:

• Wild-type CDH1 expression controls to establish baseline function

• Empty vector controls for transfection experiments

• Isogenic cell lines differing only in CDH1 status

• Rescue experiments to confirm variant-specific effects

• Pharmacological interventions that target downstream pathways (e.g., MAPK inhibitors)

• Both heterozygous and homozygous variant models to assess dosage effects

How should researchers account for potential off-target effects in CDH1 gene editing?

When employing CRISPR/Cas9 or other gene editing approaches:

• Design multiple guide RNAs with minimal predicted off-target sites

• Sequence verify edited clones for intended modifications

• Screen for potential off-target modifications at predicted sites

• Use multiple independently derived clones to confirm phenotypes

• Consider complementary approaches (siRNA, shRNA) to validate findings

• Include wild-type cells subjected to the editing protocol as controls

What approaches can resolve contradictory findings in CDH1 research?

Contradictory findings in CDH1 research can stem from multiple sources:

• Cell type-specific effects (epithelial versus neural contexts)

• Variant-specific functional impacts

• Differences in experimental conditions and assay sensitivity

• Varying genetic backgrounds of experimental models

• Heterogeneity in patient populations

To resolve these contradictions, researchers should employ multiple complementary approaches, carefully document experimental conditions, and consider context-specific effects of CDH1 variants.

How can CDH1 variant functional data be integrated with clinical observations?

Effective translation of basic research findings requires integration with clinical data:

• Correlate variant functional effects with patient tumor characteristics

• Track genotype-phenotype relationships across families

• Assess variant impacts on age of disease onset

• Consider organ-specific manifestations of different variants

• Develop functional classification systems with clinical predictive value

What emerging screening approaches are being developed for CDH1-related cancers?

Novel approaches for early detection include:

• Confocal endoscopic microscopy for gastric cancer screening, which attaches a small microscope to an endoscope to provide detailed visualization of the stomach lining, potentially offering improved sensitivity over conventional endoscopy

• Cambridge Protocol for endoscopic surveillance

• Liquid biopsy approaches to detect circulating tumor DNA with CDH1 mutations

• Multi-modal imaging technologies for both gastric and breast cancer screening

What psychosocial factors should researchers consider when studying hereditary CDH1 syndromes?

Research into hereditary cancer syndromes must consider psychosocial dimensions:

• Disclosure challenges for young adults with CDH1 mutations in dating contexts

• Decision-making processes regarding prophylactic surgeries

• Long-term quality of life following preventive interventions

• Family communication patterns about genetic risk

• Cultural factors influencing genetic testing uptake and medical management decisions

How is CDH1 implicated in cancers beyond gastric and breast cancer?

Recent evidence suggests CDH1's role extends beyond its established associations:

• Brain tumors: CDH1 variants are significantly overrepresented in glioma families (13.3%) compared to controls (1.7%)

• Oligodendrogliomas: CDH1 variants are found in 6% of IDH-mutant, 1p/19q-codeleted oligodendrogliomas

• Pituitary adenomas: Observed at higher rates in CDH1 mutation carriers

These findings suggest CDH1's tumor suppressive function spans multiple tissue types and warrant further investigation into tissue-specific mechanisms.

What therapeutic opportunities might emerge from advanced understanding of CDH1 biology?

Deeper mechanistic understanding of CDH1 creates potential therapeutic avenues:

• MAPK pathway inhibitors to modulate dysregulated β-catenin signaling

• WNT pathway modulators for CDH1-deficient tumors

• Cell adhesion mimetics to restore lost functionality

• Synthetic lethality approaches targeting dependencies created by CDH1 loss

• Immunotherapeutic approaches leveraging altered cell surface presentation in CDH1-mutant cells

How might multi-omics approaches enhance CDH1 research?

Integrative approaches offer comprehensive insights:

• Whole-genome sequencing to identify novel CDH1 variants

• Transcriptomics to assess global expression changes

• Proteomics to map altered protein interaction networks

• Metabolomics to identify downstream metabolic vulnerabilities

• Single-cell analyses to resolve cellular heterogeneity in responses

• Spatial transcriptomics to map tissue-specific effects of CDH1 loss