Epidermal Growth Factor Receptor (EGFR)

EGFR is a receptor tyrosine kinase that binds ligands including EGF, TGF-alpha, and heparin-binding EGF, triggering homo- and heterodimerization and autophosphorylation. Upon activation, EGFR recruits adapter proteins like GRB2 and engages multiple downstream signaling cascades including RAS-RAF-MEK-ERK, PI3K-AKT, PLCγ-PKC, and STAT pathways (UniProt: P00533). The receptor also regulates cell migration, learning, and memory performance.

In the brain, EGFR participates in mammalian pain signaling and cognitive functions. Beyond neurobiology, EGFR is implicated in lung cancer and neonatal nephrocutaneous inflammatory syndrome (UniProt: P00533).

EGFR exhibits elevated levels in Alzheimer's disease: analysis of post-mortem AD brain tissue versus age-matched controls showed upregulation with a mean log₂ fold-change of +0.53 (Chaparral AD proteomics). This upregulation suggests potential involvement in AD-associated pathophysiology, though the functional significance of increased EGFR in AD requires further investigation.