Sclerostin induced tumor growth, bone metastasis and osteolysis in breast cancer

Breast cancer is the second leading cause of cancer-related deaths among women worldwide. Many patients suffer from bone metastasis. Sclerostin, a key regulator of normal bone remodeling, is critically involved in osteolytic bone diseases. However, its role in breast cancer bone metastasis remains unknown. Here, we found that sclerostin was overexpressed in breast cancer tumor tissues and cell lines. Inhibition of sclerostin by antibody (Scl-Ab) significantly reduced migration and invasion of MDA-MB-231 and MCF-7 cells in a time-and dose-dependent manner. In xenograft model, sclerostin inhibition improved survival of nude mice and prevented osteolytic lesions resulting from tumor metastasis. Taken together, sclerostin promotes breast cancer cell migration, invasion and bone osteolysis. Inhibition of sclerostin may serve as an efficient strategy for interventions against breast cancer bone metastasis or osteolytic bone diseases.