Antibody Treatment May Reduce Bone Damage by 80 Percent in Osteosarcoma Patient

By Admin at 4 Apr 2016, 16:30 PM

Osteosarcoma is a rare form of primary bone cancer that typically affects children and young adults. The invasive tumor growth that occurs with osteosarcoma leads to extensive bone destruction and, often, amputations.

New research published in The Journal of Pathology revealed a novel treatment that may protect bones and reduce amputations in people with osteosarcoma. While many forms of cancer can cause bone damage, this occurs when cancer cells from a tumor elsewhere in the body spread to the bones (metastasis).

It turns out that osteosarcoma damages bones differently from metastasized cancer cells, and this discovery was key to finding the new treatment. In osteosarcoma, the cancer cells express specialized enzymes and receptors that degrade bone tissue directly.

The receptor uPARAP/Endo180 is known to be involved in bone matrix turnover during normal bone growth. The new study revealed it may also be a key player in the bone degeneration of advanced osteosarcoma tumors, possibly following an attack on bone by osteoclasts (bone cells that break down bone tissue) in the early tumor stage.

Researchers used an antibody to target this newly discovered bone degradation pathway and inactivate the uPARAP/Endo180 receptor. This reduced bone degradation by up to 80 percent in a mouse model of osteosarcoma.

Lars Engelholm of the University of Copenhagen, Denmark, explained that by treating mice with osteosarcoma with the new antibody, they were able to block the micro-processes osteosarcoma cells use to degrade bones, thereby protecting the bone tissue. Researcher Clement Trovik from Haukeland University Hospital in Norway added:

“For cancer patients, especially children and young adults, amputation of an arm or a leg is a very serious consequence of illness and we have for years been searching for therapeutics to prevent cancer-induced bone degradation.

These new results show promising results for such future treatments. Treatment with the new antibody will, in addition to the traditional treatment, enable us to save more bone tissue for reconstruction and thereby prevent amputations.”

The finding is just one of a number of potential new treatments for osteosarcoma. Immunotherapy drugs, including muramyl tripeptide (MTP or mifamurtide), may help the patient’s immune system to attack osteosarcoma cells. Adding MTP to chemotherapy has been found to benefit some patients. There are other forms of antibody therapy being studied as well. The American Cancer Society explained:

“Doctors are … studying new medicines that target specific molecules on the cancer cells. These are known as targeted therapies. Some of these are man-made versions of immune system proteins, known as monoclonal antibodies.

These antibodies attach to certain proteins on the cancer cell and help to stop the growth or kill the cancer cells. Examples now being studied include antibodies against the insulin-like growth factor receptor 1 (IGF-1R), a protein that may help cancer cells grow.”

Gateway-Funded Clinical Trial Success Story: Meet Maddy, Osteosarcoma Survivor

At Age 17, Maddy Oliver was diagnosed with osteosarcoma, an aggressive bone malignancy with one of the lowest survival rates for pediatric cancer. Watch Maddy's update one and a half years after completion of her cancer clinical trial.

See more Gateway funded clinical trial success stories here.