Health Watch -- Treating Prostate Cancer

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A drug that's been used to treat enlarged prostate also may reduce the risk of prostate cancer.

The drug finasteride has been used to treat patients with non-cancerous enlarged prostate glands. Now results of the Prostate Cancer Prevention Trial show that the drug, known by the brandname Proscar, also can help delay or prevent prostate cancer. But while the drug can lower the risk for prostate cancer by up to 25 percent, it also has some side effects, including raising the risk for high-grade prostate cancer in some patients.

The drug works by preventing testosterone from being converted to an androgen involved in the development of prostate cancer. This drug is the result of decades worth of research conducted at UT Southwestern Medical Center at Dallas.

Back in the 1970s, UT Southwestern researcher Dr. Jean Wilson noticed that men with a certain genetic deficiency didn't develop enlarged prostates or prostate cancer. He suspected that affecting the action of this gene might lead to a treatment. Later, he identified the genes responsible for the enzyme that appeared to affect the development of prostate cancer. In the 1990s, UT Southwestern molecular geneticist Dr. David Russell cloned the critical enzyme. Other researchers were then able to build on this work to develop the drug finasteride, or Proscar. The drug reduces the size of enlarged prostates, helping relieve symptoms without the need for surgery.

The researchers had long theorized that the drug could also help prevent prostate cancer, and now it appears that research has proved them right.