In a pilot clinical study, termed BRCA-D, the proliferation marker Ki67 was significantly down-regulated in the breast biopsy of BRCA1 mutation carriers who received short-term treatment with Denosumab, suggesting that RANKL inhibition may be a feasible method for the chemo-prevention of breast cancer in women with BRCA1 mutations. The gene discussed is TNFSF11; the disease is breast carcinoma.