The ANPEP gene encodes the enzyme aminopeptidase N, which has diverse biological functions, particularly in peptide digestion and cellular signaling. Below are additional details on the gene, including associations, aging, drugs, pathways, and biological processes.

### 1. Associated Genes

While the summaries primarily mention CD13 and other cell types, ANPEP has associations with several other genes involved in similar or related biological functions, including:

- **SLC6A19**: This gene encodes an amino acid transporter that may interact with ANPEP in amino acid transport mechanisms.
- **ACE** (Angiotensin I Converting Enzyme): Involved in the renin-angiotensin system, closely related to ANPEP's role in processing regulatory peptides.
- **MHC Class II Genes**: Such as **HLA-DR**, as ANPEP may process peptides bound to these molecules during antigen presentation.

### 2. Aging and Age-Related Diseases

ANPEP is implicated in various processes that may influence aging and age-related diseases:

- **Cancer**: Altered expression and activity of ANPEP have been associated with tumor growth and metastasis. Its involvement in angiogenesis suggests a role in the progression of age-related cancers.
- **Neurodegenerative Diseases**: Through its action in the central nervous system and interactions with various neuropeptides, ANPEP might influence neurodegeneration processes.
- **Inflammatory Diseases**: Given its expression in immune cells and its role in processing cytokines/chemokines, variations in ANPEP function could be associated with inflammation-related age diseases.

### 3. Drug Interactions

Though specific drugs targeting ANPEP may not be extensively detailed, the following classes of drugs are known to interact indirectly:

- **Antihypertensives**: Drugs that target the renin-angiotensin system (e.g., ACE inhibitors) may influence the pathways involving ANPEP, especially in cardiovascular contexts.
- **Anticancer Agents**: Since ANPEP is involved in tumorigenesis, compounds that affect angiogenesis or metalloproteases could have interactions, albeit not directly with the ANPEP enzyme.
- **Immunomodulators**: Drugs that affect immune responses may interact with ANPEP due to its role in peptide processing and presentation on antigen-presenting cells.

### 4. Pathways and Biological Processes

ANPEP is involved in several important biological pathways and processes, including:

- **Peptide and Protein Metabolism**: It plays a critical role in the final digestion of peptides and the processing of various bioactive peptides.
- **Angiogenesis**: It is involved in the promotion of blood vessel formation, impacting tumor growth and inflammatory responses.
- **Cytokine and Chemokine Processing**: ANPEP may modulate the activity of these signaling molecules, affecting immune responses and inflammation.
- **Cell Signaling**: It connects to pathways involved in amino acid transport and cellular communication, potentially impacting various physiological processes.

The detailed understanding of ANPEP and its functions continues to evolve, emphasizing its importance in metabolism, immunity, cancer biology, and possibly the aging process.