We observed strong inhibition of cell viability (Figure 6B) and apoptosis induction (Figure 6C, Figure S5 in the Supplementary Materials) in AMO-bzb cells transfected with synthetic siRNA#1 and treated with bortezomib, confirming that PSMβ5 down-regulation sensitizes bortezomib-resistant MM cells to the drug. Here, PSMB5 is linked to Miyoshi myopathy.