CDH16 Antibody

What is CDH16 and what is its molecular characterization?

The protein has a calculated molecular weight of 90 kDa, though Western blot analysis typically detects it at approximately 130 kDa due to post-translational modifications . As a member of the cadherin family, CDH16 contributes to cell-cell adhesion and preferentially interacts with itself in a homophilic manner, potentially contributing to the sorting of heterogeneous cell types .

What tissue types express CDH16 and how can researchers detect it?

CDH16 expression has been primarily detected in:

• Kidney tubular epithelial cells

• Thyroid follicular cells

• Cauda epididymis

• Mesonephric remnants

Immunohistochemical analysis has revealed membranous CDH16 staining in 100% of normal thyroid tissues, 86% of follicular adenomas, and 60% of follicular carcinomas . In contrast, only 6.6-9.4% of papillary thyroid carcinomas (PTCs) show CDH16 positivity, making it a potential diagnostic marker for distinguishing these entities .

In renal tissues, CDH16 positivity is frequent in various renal cell tumor subtypes:

• 100% of nephrogenic adenomas

• 98% of oncocytomas

• 97% of chromophobe renal cell carcinomas

• 85% of clear cell renal cell carcinomas

• 76% of papillary renal cell carcinomas

Detection methods include Western blot, immunohistochemistry, and immunofluorescence, with antibodies showing reactivity to human, mouse, and rat samples .

What are the recommended applications and dilutions for CDH16 antibodies?

Based on validated research protocols, the following applications and dilutions are recommended:

For immunohistochemistry of human kidney and renal cell carcinoma tissues, antigen retrieval with TE buffer pH 9.0 is recommended, though citrate buffer pH 6.0 may be used as an alternative . It is advisable to titrate the antibody in each testing system to obtain optimal results, as optimal dilutions may be sample-dependent .

How does CDH16 expression relate to cancer development and progression?

CDH16 demonstrates significant potential as a diagnostic and prognostic marker, particularly in thyroid and renal cancers. Downregulation of CDH16 appears to be a critical event in carcinogenesis of certain tissues.

In papillary thyroid carcinoma (PTC), loss of CDH16 expression is significantly associated with aggressive tumor characteristics including:

• Bilaterality (OR 2.11; 95% CI 1.68–2.64; p < 0.0001)

• Multifocality (OR 1.71; 95% CI 1.39–2.10; p < 0.0001)

• Extrathyroidal extension (OR 3.91; 95% CI 3.13–4.89; p < 0.0001)

• Lymphovascular invasion (OR 1.86; 95% CI 1.46–2.39; p < 0.0001)

• Tall cell variant morphology (p = 0.0055)

• Distant metastasis (OR 2.44; 95% CI 1.45–4.13; p = 0.0008)

Multivariate logistic regression analysis has established CDH16 as an independent predictor for lymph node metastasis (Odds ratio = 2.46; 95% CI = 1.60–3.79; p < 0.0001) . Furthermore, CDH16 loss is associated with shorter disease-free survival (p = 0.0015), suggesting its value as a prognostic marker .

The mechanism likely involves disruption of cell-cell adhesion, promoting cellular detachment and subsequent metastatic progression . These findings suggest that CDH16 could potentially serve as a therapeutic target for aggressive thyroid cancers.

How can researchers effectively use CDH16 in differential diagnosis of neoplasms?

CDH16 immunohistochemistry has emerged as a valuable tool for differential diagnosis across several tumor types, particularly in distinguishing subtypes of thyroid and renal neoplasms.

For thyroid tumors, CDH16 demonstrates distinct staining patterns:

• Present in 100% of normal thyroid tissues

• Present in 86% of follicular adenomas

• Present in 60% of follicular carcinomas

• Present in only 6.6-9.4% of papillary thyroid carcinomas

This stark contrast in expression makes CDH16 a potentially powerful component of diagnostic panels for distinguishing papillary thyroid carcinomas from other thyroid lesions. The significantly reduced expression in papillary carcinomas compared to normal thyroid tissue (p < 0.0001) underscores its diagnostic utility .

For renal tumors, CDH16 positivity frequencies vary:

• 100% of nephrogenic adenomas

• 98% of oncocytomas

• 97% of chromophobe renal cell carcinomas

• 85% of clear cell renal cell carcinomas

• 76% of papillary renal cell carcinomas

Researchers should incorporate CDH16 as part of a comprehensive immunohistochemical panel rather than as a standalone marker. When designing such diagnostic panels, it's essential to include complementary markers that can address potential overlap in expression patterns among different tumor types.

What methodological considerations are important when studying correlations between CDH16 and genetic alterations?

Research has identified important correlations between loss of CDH16 expression and genetic alterations, particularly in thyroid cancer. When designing studies to investigate these relationships, researchers should consider:

• Comprehensive molecular profiling: Studies have shown correlations between CDH16 loss and BRAF and TERT mutations in papillary thyroid carcinoma . Researchers should employ Sanger sequencing or next-generation sequencing approaches to analyze these mutations concurrently with CDH16 expression studies.

• Stratification of patient cohorts: Patients with both CDH16 negative expression and TERT mutation exhibited the shortest disease-free survival (p < 0.0001) . Researchers should stratify patient cohorts based on combinations of molecular alterations to identify synergistic effects.

• Multivariate analysis: To establish CDH16 as an independent predictor, multivariate logistic regression analysis should be performed to control for confounding variables .

• Survival analysis: Kaplan-Meier curves should be employed to assess disease-free survival in relation to CDH16 expression status and genetic alterations .

• Validation cohorts: Findings should be validated in independent patient cohorts to ensure reproducibility and clinical applicability.

This integrated approach allows researchers to establish robust associations between CDH16 expression, genetic alterations, and clinical outcomes, potentially identifying new therapeutic targets.

What are the critical quality control measures for CDH16 antibody experiments?

When using CDH16 antibodies for research applications, several quality control measures should be implemented:

• Positive controls: Always include known positive controls such as normal kidney tissue, normal thyroid tissue, or HEK-293 cells, which have been validated to express CDH16 .

• Negative controls: Include tissues known to be negative for CDH16 expression or use appropriate isotype controls to evaluate non-specific binding.

• Antigen retrieval optimization: For immunohistochemistry, compare antigen retrieval methods. Research suggests that TE buffer pH 9.0 is optimal, though citrate buffer pH 6.0 may be used as an alternative .

• Antibody validation: Confirm antibody specificity through knockdown/knockout experiments. Published literature has validated CDH16 antibodies in such applications .

• Molecular weight verification: When performing Western blot analysis, verify that the detected band appears at the observed molecular weight of approximately 130 kDa, despite the calculated weight of 90 kDa .

• Membrane preparation: Since CDH16 is a membrane-bound protein, ensure proper membrane fraction preparation when performing biochemical analyses.

Implementing these quality control measures will enhance the reliability and reproducibility of CDH16 antibody-based experiments.

How should researchers interpret discrepancies in CDH16 detection across different studies and methods?

Several factors may contribute to variability in CDH16 detection across different studies:

• Antibody clone variations: Different studies have reported varying rates of CDH16 positivity in papillary thyroid carcinomas, ranging from 6.6-9.4% to 51.4% . These discrepancies may be attributed to differences in antibody clones, detection systems, or scoring criteria.

• Sample size considerations: Studies with larger sample sizes (such as those examining over 1,600 PTC cases ) may provide more reliable prevalence data compared to smaller studies (such as those examining only 35 cases ).

• Methodological differences: Different detection methods (Western blot, immunohistochemistry, immunofluorescence) may yield varying results due to differences in protein conformation, epitope accessibility, or antibody sensitivity.

• Scoring criteria: Variations in scoring criteria for positivity (percentage of positive cells, intensity thresholds) may contribute to discrepancies between studies.

• Tissue processing variables: Fixation time, processing methods, and storage conditions can affect antigen preservation and detection.

To address these issues, researchers should clearly document methodological details, validate findings across multiple detection methods, and consider performing meta-analyses of published data to establish consensus on CDH16 expression patterns.

What are promising research avenues for therapeutic targeting of CDH16?

Given the association between loss of CDH16 expression and aggressive tumor characteristics, several therapeutic approaches warrant investigation:

• CDH16 restoration strategies: Developing methods to restore CDH16 expression in tumors showing downregulation might inhibit metastatic potential. This could involve epigenetic modifiers if CDH16 silencing is mediated by promoter methylation.

• Targeting downstream pathways: Identifying and targeting molecular pathways activated by CDH16 loss could provide alternative therapeutic approaches, particularly in aggressive papillary thyroid carcinomas.

• Combination therapies: Research suggests that patients with both CDH16 negative expression and TERT mutation exhibited the shortest disease-free survival . This indicates potential for developing combination therapies targeting both alterations.

• CDH16-based immunotherapy: Exploring the potential of CDH16 as a target for antibody-drug conjugates or engineered T-cell therapies in tumors maintaining CDH16 expression.

• CDH16 as a biomarker for therapy selection: Investigating whether CDH16 status can predict response to conventional therapies, potentially guiding personalized treatment approaches.

These avenues represent promising directions for translating CDH16 research into clinical applications. As noted by researchers, "downregulation of CDH16 in PTC might be a potential target for designing novel therapeutic strategies to treat PTC" .

How can interaction studies of CDH16 with other cadherins inform research design?

As a member of the cadherin family, CDH16 likely interacts with other cadherins and adhesion molecules. Understanding these interactions can inform more sophisticated research approaches:

• Co-immunoprecipitation studies: Designing experiments to identify binding partners of CDH16 in kidney and thyroid tissues.

• Proximity ligation assays: Employing these techniques to visualize protein-protein interactions involving CDH16 within tissue contexts.

• Competitive binding studies: Understanding whether other cadherins compensate for CDH16 loss in tumor progression.

• Cadherin switching analysis: Investigating whether downregulation of CDH16 is accompanied by upregulation of other cadherins (such as N-cadherin), potentially contributing to epithelial-mesenchymal transition.

• Functional redundancy experiments: Determining whether other kidney-expressed cadherins can compensate for CDH16 loss through overexpression studies.

These approaches can reveal the complex interplay between CDH16 and the broader cellular adhesion network, potentially identifying new therapeutic targets and diagnostic markers.