Anti-EGFR Therapy: Mechanism and Advances in Clinical Efficacy in Breast Cancer
Figure 2
(a) Basic Structure of EGFR demonstrating relevant domains. (I) The extracellular domains: (1) domain I: L1; (2) domain II:
CR1; domain III: L2; domain IV: CR2. (II)
Transmembrane domains. (III) The intracellular domains (1) juxtamembrane domain;
(2) tyrosine kinase domain; (3) regulatory region domain. The phosphorylation
of several substrates by the tyrosine kinase domain of the EGFR receptor is
responsible for activating the various signaling cascades seen in Figure 1. (b) Structure of domains I–IV of EGFR (no ligand bound). Note the
“protruding loop” in domain II (CR1) directed away from the C-shaped region of the ligand-binding zone formed by domains I, II,
and III. (c) The tyrosine kinase domain of
EGFR showing the N-lobe and C-lobe flanking the activation loop and active site
cleft [2, 3].
