In primary MCL samples, because we could not assess the effect of bortezomib on proteasome activity in each case due to limitation of MCL cell number, we treated samples with both 20 nM and 100 nM bortezomib when determining its effect on NF-κB activation to ensure that sufficient proteasome inhibition was attained. Here, NFKB1 is linked to mantle cell lymphoma.