In isolated mononuclear cells from healthy donors and patients with multiple myeloma, I-BET151 inhibits NF-κB signaling pathways in monocytes in a dose-dependent manner and diminishes the expression of osteoclast-specific genes, such as TRACP, MMP9, Ctsk, and c-Src, all of which contributes to the inhibition of osteoclast formation. The gene discussed is NFKB1; the disease is plasma cell myeloma.