BG45 is an HDAC I type inhibitor with IC50 of 289 nM, 2.0 μM, 2.2 μM and >20 μM for HDAC3/1/2/6 in cell-free assays, respectively.

HDAC3:289 nM, HDAC1:2 μM, HDAC2:2.2 μM, HDAC6:>20 μM

BG45 causes significant cell growth inhibition and induces caspase-dependent apoptosis in a series of MM cells. In RPMI8226 cells, BG45 synergistically enhances bortezomib-induced cytotoxicity. [1]

In mice bearing MM.1S xenograft of human MM, BG45 (50 mg/kg, i.p.) significantly inhibits MM tumor growth. When in combination with bortezomib, BG45 (50 mg/kg, i.p.) enhances bortezomib-induced cytotoxicity. [1]

Kinase assays: Initial rate constants are measured at 21 °C in the presence of 100 mM HEPES (pH 7.5), 0.3 mg/mL poly(Glu-Tyr) peptide substrate, 10 mM MgCl2, 1 mg/mL bovine serum albumin, 5% DMSO, 20 nM MET-KD and various concentrations of ATP and SGX523. Total reaction volumes (20 μL) are quenched with 20 μL Kinase-Glo detection buffer. Luminescence is detected in a plate-reading luminometer and the results are analyzed by nonlinear regression.

The growth inhibitory effects of BG45 in MM cell lines are assessed by measuring 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide (MTT) dye absorbance. To measure proliferation of MM cells, the rate of DNA synthesis is measured by [3H]thymidine uptake.(Only for Reference)