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Press Release
Anti-cancer Compound Crosses Blood-brain Barrier in Animal Study
November 30, 2005
An cancer-fighting compound developed in the New Orleans lab of VA Nobel laureate Andrew Schally, PhD, was able to penetrate the blood-brain barrier in recent animal research, representing a potentially important advance in the treatment of human brain cancer. The research team included William Banks, MD, director of the Geriatric Research, Education and Clinical Center at the St. Louis VA Medical Center.
The blood-brain barrier is a network of blood vessels with tightly-knit cells that keeps harmful substances from passing from the bloodstream into the brain. This barrier, however, also keeps out many potentially helpful agents, including most chemotherapy drugs. Researchers are experimenting with promising techniques to bypass the blood-brain barrier, but brain cancer remains one of the most aggressive and difficult-to-treat cancers.
Schally's compound, JV-1-42, blocks growth-hormone-releasing hormone (GHRH), believed to be a growth factor for tumors. In previous studies in his lab, related compounds shrunk human-derived tumors implanted in mice. The question remained, though, as to whether the GHRH antagonists could sneak through the blood brain barrier.
In the new study, the researchers labeled JV-1-42 with a radioactive tracer and injected it into the mice. They then examined brain tissue from the mice and found that the drug had penetrated into the brain at therapeutic levels, suggesting it might work similarly in humans.
"The compound is promising," said Banks, an authority on delivering drugs to the brain. He noted that one reason why the drug may be able to cross the blood-brain barrier is that unlike most chemotherapy drugs, it is basically nontoxic to healthy cells. "It acts as a growth inhibitor, rather than as a metabolic poison," said Banks. "It should only target cells with GHRH receptors."
"That's the advantage—no side effects," added Schally. "That's why we're so keen to develop these compounds." The researcher, who shared the 1977 Nobel Prize for Medicine with another VA researcher, Rosalyn Yarrow, said his lab has spent more than a decade exploring GHRH antagonists as a potential cancer treatment. "These compounds work not only in brain tumors, but they're very potent in prostate and breast cancer, and other tumors," he said. "They affect 16 cancers that represent major international health problems."
Banks' and Schally's team included lead author Laura Jaeger, a doctoral student at St. Louis University, where Banks is a professor of geriatrics; and Jozsef L. Varga, of Schally's lab. Their study appeared in the Aug. 30, 2005, Proceedings of the National Academy of Sciences.
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