Recombinant Human EGFR (ErbB1)

Epidermal growth factor receptor (EGFR, also known as ErbB1 or HER-1), along with receptors ErbB2, ErbB3, and ErbB4, belongs to the receptor tyrosine kinase superfamily and is a transmembrane glycoprotein that activates various signaling pathways fundamental to cellular proliferation, differentiation, and survival1, 2.

EGFR consists of an extracellular ligand binding domain, a single transmembrane domain, and an intracellular carboxyl-terminal domain with intrinsic tyrosine activity that, following ligand binding, is responsible for the phosphorylation of signaling molecules and serves as a docking site for intracellular adaptor proteins1, 2.

Seven ligands are known to activate EGFR: epidermal growth factor (EGF), transforming growth factor-⍺, heparin-binding EGF, β-cellulin, amphiregulin, epiregulin, and epigen. EGFR plays important roles during embryogenesis and organogenesis and in the growth, differentiation, maintenance, and repair of adult tissues, including the nervous system2.

Additionally, EGFR plays a role in skin homeostasis2, angiogenesis in wound healing2, kidney physiology2, and autophagy3.

Dysregulation and somatic mutation of EGFR are associated with disease and cancer.

Changes to EGFR expression and/or signaling pathways that impact EGFR function are associated with Parkinson’s disease2, Alzheimer’s disease1, 2, and amyotrophic lateral sclerosis2.

In several human cancers (lung, glioblastoma, brain, breast, colorectal, ovarian), EGFR signaling is altered due to EGFR gene amplification and/or protein overexpression, mutations, or in-frame deletions3.

Inappropriate activation of EGFR in cancer can also result from abnormal receptor endocytosis and trafficking.

EGFR is the target of multiple cancer therapies, including monoclonal humanized antibodies and selective small molecule inhibitors.

Additionally, EGFR is a host factor that facilitates viral entry for hepatitis B4, hepatitis C5, and gastroenteritis6.

EGFR also plays a role in SARS-CoV-2 infection and is a possible target of antiviral therapy7, 8, 9.