3g5v

Antibodies Specifically Targeting a Locally Misfolded Region of Tumor Associated EGFR

spinqualitylabelsall models 3g5v, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3g5v is a 3 chain structure with sequence from Homo sapiens and Mus musculus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.001Å Ligands: ACT, FMT, GOL Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease EGFR_HUMAN Defects in EGFR are associated with lung cancer (LNCR) [MIM:211980. LNCR is a common malignancy affecting tissues of the lung. The most common form of lung cancer is non-small cell lung cancer (NSCLC) that can be divided into 3 major histologic subtypes: squamous cell carcinoma, adenocarcinoma, and large cell lung cancer. NSCLC is often diagnosed at an advanced stage and has a poor prognosis. Function EGFR_HUMAN Receptor tyrosine kinase binding ligands of the EGF family and activating several signaling cascades to convert extracellular cues into appropriate cellular responses. Known ligands include EGF, TGFA/TGF-alpha, amphiregulin, epigen/EPGN, BTC/betacellulin, epiregulin/EREG and HBEGF/heparin-binding EGF. Ligand binding triggers receptor homo- and/or heterodimerization and autophosphorylation on key cytoplasmic residues. The phosphorylated receptor recruits adapter proteins like GRB2 which in turn activates complex downstream signaling cascades. Activates at least 4 major downstream signaling cascades including the RAS-RAF-MEK-ERK, PI3 kinase-AKT, PLCgamma-PKC and STATs modules. May also activate the NF-kappa-B signaling cascade. Also directly phosphorylates other proteins like RGS16, activating its GTPase activity and probably coupling the EGF receptor signaling to the G protein-coupled receptor signaling. Also phosphorylates MUC1 and increases its interaction with SRC and CTNNB1/beta-catenin. Isoform 2 may act as an antagonist of EGF action. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Epidermal Growth Factor Receptor (EGFR) is involved in stimulating the growth of many human tumors, but the success of therapeutic agents has been limited in part by interference from the EGFR on normal tissues. Previously, we reported an antibody (mab806) against a truncated form of EGFR found commonly in gliomas. Remarkably, it also recognizes full-length EGFR on tumor cells but not on normal cells. However, the mechanism for this activity was unclear. Crystallographic structures for Fab:EGFR(287-302) complexes of mAb806 (and a second, related antibody, mAb175) show that this peptide epitope adopts conformations similar to those found in the wtEGFR. However, in both conformations observed for wtEGFR, tethered and untethered, antibody binding would be prohibited by significant steric clashes with the CR1 domain. Thus, these antibodies must recognize a cryptic epitope in EGFR. Structurally, it appeared that breaking the disulfide bond preceding the epitope might allow the CR1 domain to open up sufficiently for antibody binding. The EGFR(C271A/C283A) mutant not only binds mAb806, but binds with 1:1 stoichiometry, which is significantly greater than wtEGFR binding. Although mAb806 and mAb175 decrease tumor growth in xenografts displaying mutant, overexpressed, or autocrine stimulated EGFR, neither antibody inhibits the in vitro growth of cells expressing wtEGFR. In contrast, mAb806 completely inhibits the ligand-associated stimulation of cells expressing EGFR(C271A/C283A). Clearly, the binding of mAb806 and mAb175 to the wtEGFR requires the epitope to be exposed either during receptor activation, mutation, or overexpression. This mechanism suggests the possibility of generating antibodies to target other wild-type receptors on tumor cells. Antibodies specifically targeting a locally misfolded region of tumor associated EGFR.,Garrett TP, Burgess AW, Gan HK, Luwor RB, Cartwright G, Walker F, Orchard SG, Clayton AH, Nice EC, Rothacker J, Catimel B, Cavenee WK, Old LJ, Stockert E, Ritter G, Adams TE, Hoyne PA, Wittrup D, Chao G, Cochran JR, Luo C, Lou M, Huyton T, Xu Y, Fairlie WD, Yao S, Scott AM, Johns TG Proc Natl Acad Sci U S A. 2009 Mar 31;106(13):5082-7. Epub 2009 Mar 16. PMID:19289842 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Epidermal growth factor receptor 3D structures

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