To further elucidate the role of OPG in breast carcinogenesis, OPG was knocked down using a specific OPG siRNA in the triple-negative breast cancer (TNBC) cells, namely MDA-MB-231 and BT-20, while a scrambled sequence was utilized as a control (OPG-si and Ctrl, respectively). The gene discussed is TNFRSF11B; the disease is triple-negative breast carcinoma.