To directly assess the contribution of RelB on anti-apoptotic NF-κB signature expression in MM cells, we developed a stable RelB knockdown approach by RNA interference in RelB-positive MM cell lines using either a lentivirus carrying a shRNA targeting RelB or a scrambled control, and analyzed anti-apoptotic NF-κB target gene expression. This evidence concerns the gene NFKB1 and Miyoshi myopathy.