Further mechanistic studies in mature osteoclasts confirmed the mechanism of action by which IKKβIII and IKKβV exerted their anti-osteoclast effects by preventing RANKL-induced IκB phosphorylation and partial inhibition of these same pathways when activated with tumour-derived factors from the human MDA-231 breast cancer cells. The gene discussed is TNFSF11; the disease is breast cancer.