A new treatment to inhibit bone destruction induced by breast cancer

Breast cancer (BC) is the most common cancer in women, worldwide. After treatment of the primary tumor, bone metastases often occur and cause bone disruption, caused by an increased activity of osteoclasts (OCs), cells that resorb bone. OCs are activated by cancer cells, which in turn inhibit osteoblasts (OBs), cells that form bone. Bone metastases also cause muscle weakness, that, to date, has no effective therapy. The treatment of BC-induced bone metastases is based on the use of antiresorptive drugs that block OC activity and the progression of bone destruction. However, no OB-targeting drugs able to stimulate new bone formation are available for the treatment of bone metastases. In a recent paper, the member of ECTS Academy, Hanna Taipaleenmäki, reported that certain types of metastatic breast cancer cells secrete sclerostin, a protein able to inhibit OBs. This led to the hypothesis that sclerostin inhibition might counteract bone metastasis formation and damage. In an experimental model they used a monoclonal anti-sclerostin antibody (Scl-Ab), and observed an increase of OB number and bone formation rate, with a corresponding decrease of OCs number and activity. Together, these effects restricted tumor burden and osteolytic bone destruction, thereby increasing the overall survival. Interestingly, the Scl-Ab treatment did not affect the function of healthy muscle, while it improved the performance of muscles damaged due to BC bone metastases. In conclusion, blocking sclerostin activity is a promising new treatment for bone metastasis and for the muscle weakness associated to this cancer condition.

See the original article here: https://www.ncbi.nlm.nih.gov/pubmed/30965315