Figure 4

Effect of BU-32 on proteasomal catalytic activity of SKBR3 cells. Proteasome inhibition by Bortezomib and BU-32 in the SKBR3 breast cancer cell line was measured. The cells were treated with different concentrations of proteasome inhibitor from 1 to 50 nM for 24 hours, and were then analyzed for the inhibition of chymotryptic-like, caspase-like, and tryptic-like intracellular proteasome activities. Results are mean of three individual experiments. RLU: Relative Luminescence Units.