Regrettably, some trials that assessed the effect of denosumab in bone metastatic breast cancer patients have been terminated without providing any essential insights (NCT03070002, NCT01952054) Notably, a novel orally available small-molecule RANKL inhibitor, AS2676293 has been found to markedly inhibit bone metastasis of human breast cancer cells in mouse models, possibly providing a more efficacious and affordable solution [86]. Here, TNFSF11 is linked to breast cancer.