EGFR (ERBB1)

What it is. Receptor tyrosine kinase that binds EGF-family ligands to drive proliferation and survival signaling.

Why it matters here. Oncogenic driver via amplification/mutation; central node for growth control and a classic drug target.

Notes. Ligand: EGF; Pathways: EGFR→RAS→MAPK; EGFR→PI3K→AKT.