### NECTIN4 Gene Overview

**Gene Symbol**: NECTIN4  
**Location**: Chromosome 1

**Function**: The NECTIN4 gene encodes a protein that is part of the nectin family, which plays an essential role in cell adhesion through both homophilic (same molecules binding to each other) and heterophilic (different molecules binding) interactions. The protein contains two immunoglobulin-like C2-type domains and one V-type domain, making it a single-pass type I membrane protein. Its soluble form is produced by the action of the metalloproteinase ADAM17/TACE.

### 1. Associated Genes

While the summaries mention NECTIN1 as a known interaction partner, NECTIN4 is also believed to be associated with or functionally relevant to several other genes involved in similar biological processes:

- **ADAM17**: The metalloproteinase responsible for cleaving NECTIN4 at the cell surface, affecting its soluble form.
- **PATJ (Pals1-associated tight junction protein)**: Involved in apical junction formation in epithelial tissues and cellular adhesion.
- **PVR (Poliovirus receptor)**: Interacts in cell adhesion and may have relevance in viral entry mechanisms, alongside other nectins.

### 2. Aging and Age-Related Diseases

Current literature does not clearly indicate direct associations of NECTIN4 with aging or age-related diseases. However, since NECTIN4 is implicated in cell adhesion and signal transduction, it could indirectly contribute to age-related cellular changes:

- **Cancer**: The secreted form of NECTIN4 has been identified in breast tumor cell lines and patients, suggesting a role in tumor biology, which may be influenced by age-related factors, particularly since cancer risk often increases with age.

- **Ectodermal Dysplasia-Syndactyly Syndrome type 1**: While not age-related per se, this autosomal recessive disorder may present developmental issues that can influence quality of life and longevity.

### 3. Drug Interactions

As of my latest data, specific drugs directly interacting with NECTIN4 are not well established. However, because NECTIN4 is involved in proteolytic processes mediated by ADAM17, drugs targeting ADAM17 (also referred to in therapeutic contexts for inflammation and cancer) may have indirect implications for actions related to NECTIN4.

- **ADAM17 Inhibitors**: These may offer insights into modulation of NECTIN4's functions since its cleavage is modulated by this protein.

### 4. Pathways and Biological Processes

NECTIN4 is involved in several key biological processes, including:

- **Cell Adhesion**: It plays a critical role in mediating cell-cell adhesion necessary for normal tissue architecture and integrity.
- **Immune Response**: Involved in interactions that can impact immune signaling pathways, although this may vary with different co-interacting proteins.
- **Tumorigenesis**: Involvement in pathways related to breast cancer, given its expression patterns in tumor cell lines and possible roles in tumor microenvironments.
- **Epithelial-Mesenchymal Transition (EMT)**: Its function may relate to processes affecting cellular migration and invasion, particularly in cancer contexts.

Overall, NECTIN4 is a significant member of the cell adhesion family, particularly in the contexts of developmental biology, pathology, and potentially therapeutic discovery related to cancer and epithelial tissue dynamics. Further research is needed to clarify its roles in aging and specific drug-target interactions.