In Vitro Cell-Free Assay: In a final reaction volume of 50 μl, CK2 ααββ (4 ng, 8.5 mU) was incubated with various concentrations of test compounds in DMSO (1 ul, 2% by volume), 20 mM MOPS pH 7.2, 10 mM EGTA, 0.15 M NaCl, 10 mM DTT, 0.002% Brij-35, 200 μM RRRDDDSDDD (SEQ ID NO.: 4), 10 mM MgAcetate, ATP 15 uM and 0.33% (by volume) (hr-3311ATP: Stock 1 mCi/100 μl; 3000 Ci/mmol (Perkin Elmer)). Reactions were maintained for 40 min at 23° C. The reactions were quenched with 100 ul of 0.75% Phosphoric acid, then transferred to and filtered through a Phosphocellulose filter plate (Millipore, MSPH-N6B-50). After washing each well 4 times with 0.75% Phosphoric acid, scintillation fluid (20 uL) was added to each well and the residual radioactivity was measured using a Wallac luminescence counter.
Inhibition Assay: 5 uM ATP: Test compounds dissolved and diluted in DMSO (2 μl) were added to a reaction mixture comprising 10 μl of 5× Reaction Buffer (40 mM MOPS pH 7.0, 5 mM EDTA), 10 μl of recombinant human PIM2 solution (4 ng PIM-2 dissolved in dilution buffer (20 mM MOPS pH 7.0; EDTA 1 mM; 5% Glycerol; 0.01% Brij 35; 0.1%; 0.1% 2-mercaptoethanol; 1 mg/ml BSA)) and 8 ul of water. Reactions were initiated by the addition of 10 ul of ATP Solution (49% (15 mM MgCl2; 5 uM ATP) 1% ([γ-33P]ATP: Stock 1 mCi/100 μl; 3000 Ci/mmol (Perkin Elmer)) and 10 ul of substrate peptide solution (RSRSSYPAGT (SEQ ID NO.: 6), dissolved in water at a concentration of 1 mM), Reactions were maintained for 10 min at 30° C. The reactions were quenched with 100 ul of 0.75% Phosphoric acid, then transferred to and filtered through a Phosphocellulose filter plate (Millipore, MSPH-N6B-50). After washing each well 4 times with 0.75% Phosphoric acid, scintillation fluid (20 uL) was added to each well and