AZD1480 is a novel ATP-competitive JAK2 inhibitor (IC50: 0.26 nM), selectivity act against Tyk2 and JAK3, and to a smaller extent against JAK1. AZD1480 has been used in trials studying the treatment of Solid Malignancies, Post-Polycythaemia Vera, Primary Myelofibrosis (PMF), and Essential Thrombocythaemia Myelofibrosis.
kinase assays: Inhibition studies of AZD1480 are performed using recombinant Jak1, Jak2, or Jak3 under buffer conditions of 50 mM HEPES pH 7.3, 1 mM DTT, 0.01% Tween-20, 50 mM/ml BSA, and 10 mM MgCl2. Jak3 enzyme is expressed as N-terminal GST fusion in insect cells and purified by glutathione-affinity and size-exclusion chromatographies. Enzymes are assayed in the presence of AZD1480 (10 point dose response, in triplicate, from 8.3 μM to 0.3 nM in half-log dilution steps) using 1.5 μM peptide substrate (Jak1: FITC-C6-KKHTDDGYMPMSPGVA-NH2, Jak2 and Jak3: FAM-SRCtide) and screened under their respective ATP Km (Jak1: 55 μM, Jak2: 15 μM, Jak3: 3 μM) and approximated physiological ATP concentration of 5 mM. Phosphorylated and unphosphorylated peptides are separated and quantified by a Caliper LC3000 system for calculating percent inhibition.
Renca or 786-O cells are suspended in DMEM medium with 5% FBS , and seeded in 96-well plates (5×103 per well) to allow adhesion and then treated with DMSO or AZD1480 for 48 hours. Cell viability is determined by MTS assay. Absorbance at 490 nm is measured with Mikrotek Laborsysteme. Mouse endothelial cells and splenic CD11b+/c- myeloid cells are enriched from tumor-bearing mice,and cultured in 5% FBS RPMI-1640 medium. HUVECs are cultured on collagen 1–coated plates in complete medium. All cells are treated with DMSO and AZD1480 at various doses for 24 hours. Cell viability is determined by counting cell number manually. All the experiments are repeated 3 times. (Only for Reference)