Metoprolol succinate is a selective adrenergic beta-1 blocking agent that is commonly used to treat ANGINA PECTORIS; HYPERTENSION; and CARDIAC ARRHYTHMIAS.

In vitro biochemical assays against histone methyltransferases: Activity against EZH2 is assessed using 5 member PRC2 complex (Flag-EZH2, EED, SUZ12, AEBP2, RbAp48). The assay protocol may be summarized as follows: 10 mM stocks of compounds are prepared from solid in 100% DMSO. An 11 point serial dilution master plate is prepared in 384 well format (1:3 dilution, columns 6 and 18 were equal volume DMSO controls) and dispensed to assay ready plates using acoustic dispensing technology to create a 100 nL stamp of compound and DMSO controls. The assay additions consisted of equal volume additions of 10 nM EZH2 and the substrate solution (5 μg/mL HeLa nucleosomes and 0.25 μM [3H]-SAM) dispensed into assay plates using a multi-drop combi dispense. Reaction plates are incubated for 1 hr and quenched with an equal volume addition of 0.5 mg/mL PS-PEI Imaging Beads (RPNQ0098) containing 0.1 mM unlabeled SAM. The plates are sealed, dark adapted for 30 minutes, and a 5 minute endpoint luminescence image is acquired using a Viewlux imager. Plate statistics such as Z' and signal to background as well as dose response curves are analyzed using Activity BaseXE. The in vitro biochemical activity of EZH1 is assessed as part of a 5 member PRC2 complex using a 384 well SPA assay identical to EZH2. Buffer components, reagent dispensing, compound plate preparation, quench conditions and data analysis are identical for EZH1 and EZH2 with final assay concentrations of 20 nM EZH1, 5 μM/mL HeLa nucleosomes and 0.25 μM [3H]-SAM. Further data analysis, pIC50 pivots and visualizations are enabled by TIBCO Spotfire. Compounds are profiled at Reaction Biology Corp. (Malvern, PA) to assess inhibition in their panel of histone methyltransferase assays. Methyltransferase activity is assessed using HotSpot technology, a miniaturized radioisotope-based filter binding assay.Inhibitors are dissolved in dimethyl sulfoxide (DMSO) and tested at concentrations up to 100 uM with a final DMSO concentration of 2%. Buffer containing the methyltrasferase at the listed concentration and its preferred substrate as shown in the accompanying table is preincubated with compound for 10 min. Reactions are initiated by the addition of 1 uM S-adenosyl-L-[methyl-3H]methionine (SAM), allowed to incubate for 60 min at 30C followed by transfer to P81 filter-paper and PBS wash before detection.