3KRR

Crystal Structure of JAK2 complexed with a potent quinoxaline ATP site inhibitor

Summary for 3KRR

• Entry DOI: 10.2210/pdb3krr/pdb
• Descriptor: Tyrosine-protein kinase JAK2, 8-[3,5-difluoro-4-(morpholin-4-ylmethyl)phenyl]-2-(1-piperidin-4-yl-1H-pyrazol-4-yl)quinoxaline (3 entities in total)
• Functional Keywords: small molecule inhibitor, atp site kinase inhibitor, atp-binding, disease mutation, kinase, membrane, nucleotide-binding, phosphoprotein, proto-oncogene, sh2 domain, transferase, tyrosine-protein kinase
• Biological source: Homo sapiens (human)
• Cellular location: Endomembrane system; Peripheral membrane protein (By similarity): O60674
• Total number of polymer chains: 1
• Total formula weight: 35213.03

Authors

Tavares, G.A.,Gerspacher, M.,Kroemer, M.,Scheufler, C. (deposition date: 2009-11-19, release date: 2010-07-21, Last modification date: 2024-10-09)

Primary citation

Baffert, F.,Regnier, C.H.,De Pover, A.,Pissot-Soldermann, C.,Tavares, G.A.,Blasco, F.,Brueggen, J.,Chene, P.,Drueckes, P.,Erdmann, D.,Furet, P.,Gerspacher, M.,Lang, M.,Ledieu, D.,Nolan, L.,Ruetz, S.,Trappe, J.,Vangrevelinghe, E.,Wartmann, M.,Wyder, L.,Hofmann, F.,Radimerski, T.
Potent and Selective Inhibition of Polycythemia by the Quinoxaline JAK2 Inhibitor NVP-BSK805
Mol.Cancer Ther., 9:1945-1955, 2010

PubMed Abstract: The recent discovery of an acquired activating point mutation in JAK2, substituting valine at amino acid position 617 for phenylalanine, has greatly improved our understanding of the molecular mechanism underlying chronic myeloproliferative neoplasms. Strikingly, the JAK2(V617F) mutation is found in nearly all patients suffering from polycythemia vera and in roughly every second patient suffering from essential thrombocythemia and primary myelofibrosis. Thus, JAK2 represents a promising target for the treatment of myeloproliferative neoplasms and considerable efforts are ongoing to discover and develop inhibitors of the kinase. Here, we report potent inhibition of JAK2(V617F) and JAK2 wild-type enzymes by a novel substituted quinoxaline, NVP-BSK805, which acts in an ATP-competitive manner. Within the JAK family, NVP-BSK805 displays more than 20-fold selectivity towards JAK2 in vitro, as well as excellent selectivity in broader kinase profiling. The compound blunts constitutive STAT5 phosphorylation in JAK2(V617F)-bearing cells, with concomitant suppression of cell proliferation and induction of apoptosis. In vivo, NVP-BSK805 exhibited good oral bioavailability and a long half-life. The inhibitor was efficacious in suppressing leukemic cell spreading and splenomegaly in a Ba/F3 JAK2(V617F) cell-driven mouse mechanistic model. Furthermore, NVP-BSK805 potently suppressed recombinant human erythropoietin-induced polycythemia and extramedullary erythropoiesis in mice and rats.

PubMed: 20587663
DOI: 10.1158/1535-7163.MCT-10-0053

Experimental method

X-RAY DIFFRACTION (1.8 Å)