Preparing and Evaluating Proteasome Inhibitors

Harmine (Tocris 5075), LDN-192960 (Sigma-Millipore SML0755), KRIBB11 (Tocris 5480), bortezomib (Selleckchem S1013), carfilzomib (Selleckchem S2853), ixazomib (Selleckchem S2180), and oprozomib (Selleckchem S7049) were dissolved in DMSO at a stock concentration of 10 mM and treatments were carried out as indicated. Curcumin (Sigma-Millipore 08511) was diluted in DMSO at a stock concentration of 5 mM in the dark and prepared fresh prior to each experiment and the excess solution was never stored. Curcumin treatment at a final concentration of 5 µM was always carried out in media containing either 1% bovine serum albumin (BSA) or 10% fetal bovine serum (FBS) to maintain maximum stability and to avoid aggregation [15 (link),19 (link)].