Faculty Focus: Wynn Volkert

Magic Bullets for Killing Cancer

Wynn Volkert develops radiopharmaceuticals, which kill cancer cells without harming healthy cells as traditional radiation therapy can. Rob Hill photo

For more than two decades, labs in the basement of the Truman Veterans Hospital have been buzzing with researchers in MU's Radiopharmaceutical Science Institute (RSI), which develops radioactive molecules that target cancer cells from inside the body. It's a welcome alternative to traditional external radiation therapy, which wreaks havoc on both good and bad cells. "This is really where nuclear medicine is going," says Wynn Volkert, director of the RSI and Curators' Professor of radiology. "We hope to be able to replace some of the external beam therapy."

Radiopharmaceuticals kill cancer cells without harming healthy cells. The specially designed radioactive molecules target receptors that are unique to different types of tissue. For example, a molecule designed to target bone does not bind to the surrounding muscle tissue. That's how the bone-cancer drug Quadramet, developed at MU in the 1980s, works. The molecules are also attracted to areas with rapid cell division — cancer's calling card.

When cancer spreads, a condition called metastasis, it becomes difficult to target the disease from outside the body. "If someone has metastatic disease, with external beam therapy, you may not know where all these cells are," Volkert says. "So the potential power would be to inject your radioactive drug to spread throughout the body, and if you've got the right homing technology, no matter where the cells are, it'll pick them up. It's the magic bullet hypothesis."

For about eight years, RSI investigators have been working with a molecular model based on a design by researcher Timothy Hoffman. "We showed the potential value of it pretty quickly," Volkert says. Already they are using the model to develop drugs to treat breast, prostate and pancreatic cancers, and they're working to target other human cancers including melanoma, lymphoma and colon cancers. Their current funding — which comes from the National Institutes of Health, the American Cancer Society, the Veterans Administration and the departments of Energy and Defense — allows the researchers to develop basic techniques and strategies for treating cancer before licensing their work out to drug companies that may be interested only in short-term results.

But the chief benefit of the institute may be the development of a cross-disciplinary approach to cancer research. "The nice thing about the institute is, we formed it to help facilitate interactions between our faculty and faculty outside the institute as well," Volkert says. "It's a group that's capable of starting from fundamental processes and concepts and moving all the way up into human patients."

Reprinted with permission of MIZZOU magazine.