CHEMBL5732752

Biochemical Assays for PI3Kalpha, PI3Kbeta: The luminescence-based ATP detection reagent KinaseGlo was obtained from Promega, (Cat. No. V6714, Lot No. 236161) through Catalys, Wallisellen, Switzerland. (L-alpha-phosphatidylinositol (PI), Liver, Bovine) were obtained from Avanti Polar Lipid (Cat. No. 840042C, Lot#LPI-274), Phosphatidylinositol-4,5-bisphosphate (PIP(4,5)2(Avanti, Cat. No. 840046X) or L-α-phosphatidylinositol (PI) was obtained from Avanti Polar Lipid (Cat. No. 840042C, Lot#LPI-274). L-α-Phosphatidylserine (PS) was from Avanti Polar Lipid (Cat. No. 840032C), n-Octylglucoside Avanti Polar Lipid (Cat. No. 10634425001). Luminescence is a well established readout to determine ATP concentrations and can thus be used to follow the activity of many kinases regardless of their substrate. The Kinase Glo Luminescent Kinase Assay (Promega, Madison/WI, USA) is a homogeneous HTS method of measuring kinase activity by quantifying the amount of ATP remaining in solution following a kinase reaction.50 nL of compound dilutions were dispensed onto black 384-well low volume Non Binding Styrene (NBS) plates (Costar Cat. No. NBS#3676) as described in section 8.2. L-α-phosphatidylinositol (PI), provided as 10 mg/ml solution in methanol, was transferred into a glass tube and dried under nitrogen beam. It was then resuspended in 3% OctylGlucoside by vortexing and stored at 4° C. 5 μL of a mix of PI/OG with the PI3Ka and Pi3Kb subtypes were added. Kinase reactions were started by addition of 5 μl of ATP-mix containing in a final volume 10 μL 10 mM TRIS-HCl pH 7.5, 3 mM MgCl2, 50 mM NaCl, 0.05% CHAPS, 1 mM DTT and 1 μM ATP, and occurred at room temperature. Reactions were stopped with 10 μl of KinaseGlo and plates were read 10 mins later in a Synergy2 reader using an integration time of 0.1 seconds per well. 2.5 μM of NVP-BGT226 (standard) was added to the assay plates to generate the 100% inhibition of the kinase reaction, and the 0% inhibition was given by the solvent vehicle (90% DMSO in water). NVP-BGT226 was used as a reference compound and included in all assay plates in the form of 16 dilution points in duplicate.IC50 values of the percentage inhibition of each compound at 8 concentrations (usually 10, 3.0, 1.0, 0.3, 0.1, 0.030, 0.010 and 0.003 μM) n=2 were derived by fitting a sigmoidal dose-response curve to a plot of assay readout over inhibitor concentration as described. All fits were performed with the program XLfit4 (ID Business Solutions, Guildford, UK).