The POFUT1 gene encodes an enzyme that plays a pivotal role in glycosylation processes and is involved in several cellular signaling pathways. Below, I will provide more details in line with your queries.

1. **Associated Genes**:
   - **NOTCH1**: POFUT1 is crucial for the proper fucosylation of NOTCH1, influencing its signaling pathway.
   - **FRINGE (RFNG)**: This gene works in tandem with POFUT1, as it modifies the fucosylation initiated by POFUT1 on NOTCH.
   - **Agrin (AGRN)**: POFUT1 fucosylates agrin, influencing its function in clustering acetylcholine receptors.
   - **EOGT (Epidermal Growth Factor O-linked Glycosylation 1)**: Although primarily involved in O-glucose glycosylation, it may relate to the pathways where POFUT1 is functional.

2. **Aging and Age-related Diseases**:
   - While direct associations of POFUT1 with aging or specific age-related diseases may require more targeted studies, its roles in signaling processes (e.g., NOTCH signaling) have implications in developmental processes, tissue homeostasis, and possibly in regenerative medicine.
   - Aberrant NOTCH signaling has been correlated with various age-related diseases, such as neurodegeneration and cancer, although a direct link between POFUT1 and these pathologies necessitates further investigation.

3. **Drug Interactions**:
   - Currently, specific drugs targeting POFUT1 have not been well characterized; however, drugs or small molecules that modulate NOTCH signaling (e.g., gamma-secretase inhibitors) may indirectly affect POFUT1's activity and its downstream effects:
     - **Gamma-secretase inhibitors**: These affect NOTCH signaling and could have downstream effects on POFUT1-mediated fucosylation.
     - **Fucosylation inhibitors**: Compounds that inhibit fucose addition might interact with POFUT1 indirectly by affecting the pathway in which it participates.

4. **Pathways and Biological Processes**:
   - **NOTCH Signaling Pathway**: POFUT1 is essential for the functional modification of NOTCH receptors, which are involved in various developmental processes.
   - **Cell Adhesion and Migration**: Through its action on agrin and related proteins, POFUT1 plays a role in muscle cell signaling and synaptic clustering.
   - **Wnt Signaling Pathway**: Some evidence indicates roles in modulating Wnt signaling.
   - **EGF Signaling Pathway**: EGF-like repeats that POFUT1 modifies are critical for EGF signaling.
   - **Protein Glycosylation**: The primary metabolic process that POFUT1 is involved in is the addition of O-fucose to proteins, affecting their stability, folding, and functionality.

In summary, POFUT1 is an integral enzyme with significant implications in cellular signaling, specifically related to the NOTCH pathway and glycosylation processes. Its roles in aging and age-related conditions as well as associations with therapeutic agents merit further investigation.