Prostate cancer remains one of the most common cancers and the second-leading cause of cancer death in American men, according to the American Cancer Society. So far, treatments for prostate cancer include drugs that affect the entire body, instead of only cancer cells. Work by a team of researchers at Purdue University offers hope they have found a new method of not only finding and targeting these cancer cells, but also carry therapeutic drugs directly to the site of infection.

The scientists have synthesized what they have termed a homing device: a molecule that finds and penetrates prostate cancer cells. The molecule attaches to a protein that is only present in 90% of all prostate cancers (prostate-specific membrane antigen, or PSMA). If the targeting molecule could be linked to new drugs being designed to destroy the vasculature of solid tumors, says Philip Low, professor of Biochemistry, then the method would kill the cancer cells directly and the vasculature that feeds the tumors.

Scientists have for many years looked to monoclonal antibodies as molecular homing devices. But the Purdue scientists used a rational-design approach. They developed their homing molecule after studying the PSMA structure in computer models.

The team also has developed imaging agents for body scans that can be linked to and be carried by the molecule. Currently, only one imaging agent for prostate cancer cells has been approved by the US Food and Drug Administration. The research team says it hopes to enter its radioimaging application into clinical trials this fall.

 A successful targeted drug delivery system would be a giant step not only in the fight against cancer but also in providing some relief to those who endure the painful side effects associated with existing therapies.