※ EGFR family introduction

    EGFRs (Epidermal growth factor receptors) are transmembrane receptor tyrosine kinases. Four members have been identified in human, EGFR/ErbB-1, HER2/ErbB-2, HER3/ErbB-3 and HER4/ErbB-4. EGFRs consist of an extracellular ligand-binding domain and a cytoplasmic region containing a kinase domain. EGFRs can be activated via binding some EGF-like molecules, TGF-α and neuregulins to extracellular domain. Ligand binding can also induce the formation of receptor homodimers or heterodimers, which will lead to some phosphorylation of tyrosine residues on one receptor, and provide docking sites for downstream signal molecules. The EGFR signaling network is highly complex, signal will be transducted from cell surface into nucleus through a variety of molecules. The signaling network will finally affect several cellular processes, including cell apoptosis, cell migration, cell growth, cell adhesion and differentiation (1).

Reference
1. Yarden, Y. (2001) The EGFR family and its ligands in human cancer. signalling mechanisms and therapeutic opportunities. Eur J Cancer, 37 Suppl 4, S3-8. PMID:11597398