DETROIT, MI - Prostate cancer may be difficult to treat, but once it spreads to the bones, it is even more devastating. If prostate cancer is not caught in its earliest stages, it metastasizes to the bones, taking on a more deadly form of the disease.

The United States Department of Defense Prostate Cancer Research Program awarded a grant to Wayne State University (WSU) researcher, Michael Cher, MD, to study gene therapy treatments to halt prostate cancer growth in bones. "Men who die of prostate cancer do so after it has spread to the skeleton," said Dr.Cher, assistant professor of urology and pathology at the Wayne State University School of Medicine. "Once the cancer spreads to the bones, it becomes more difficult to treat and impossible to cure."

Bone cancer causes severe bone destruction, which is very painful to the patient. Dr. Cher and his research associate, Dr. Jeffrey Nemeth, found that the bone destruction is caused by a group of proteins called matrixmetalloproteinases (MMPs), which are able to digest tissue. In bone biopsies from prostate cancer patients and in bone tumors in animal models, Drs. Cher and Nemeth found a sharp increase in MMP activity.

Through genetic manipulation, Dr. Cher and Dr. Nemeth are trying to program the bone cells to secrete TIMPs, a group of proteins that inhibit MMP activity. "We are training the human bone cells to create a hostile environment that will reject the cancer cells and suppress cancer growth," he said. If this strategy is successful in the animal model, the investigations could move into clinical trials.

Hormone treatment is the only therapy currently available to halt bone cancer. "Although it may put the cancer in remission for a brief time, it always ultimately fails," said Dr. Cher. Inadequate treatment modalities have contributed to prostate cancer becoming the second leading cause of cancer death in men, with lung cancer being the first.

"We're hoping that we can advance to the point where we can inject genetically modified bone cells into patients with prostate cancer bone metastases, thereby inhibiting cancer growth and increasing our likelihood of treating bone metastases before complications develop."

The Wayne State University School of Medicine is the largest single-campus medical school in the country and is fourth largest overall. As a leader in research and patient care, WSU has expertise in many areas including cancer, women's and children's health, and the neurosciences.