Arsenic Shows Promise as Cancer Treatment, Study Finds
ScienceDaily (July 15, 2010) — Miss Marple notwithstanding, arsenic might not be many people's favorite chemical. But the notorious poison does have some medical applications. Specifically, a form called arsenic trioxide has been used as a therapy for a particular type of leukemia for more than 10 years. Now researchers at the Stanford University School of Medicine have shown that it may be useful in treating a variety of other cancers.
Combining arsenic with other therapies may give doctors a two-pronged approach to beating back forms of the disease caused by a malfunction in a critical cellular signaling cascade called the Hedgehog pathway. The U.S. Food and Drug Administration has already approved arsenic trioxide for use in humans, which could pave the way for clinical trials of this approach.
"Many pharmaceutical companies are developing anticancer drugs to inhibit the Hedgehog pathway," said Philip Beachy, PhD, professor of developmental biology and the Ernest and Amelia Gallo Professor in the School of Medicine. In addition, Beachy recently identified an antifungal drug commonly used in humans, itraconazole, as a Hedgehog pathway inhibitor. "However, these compounds target a component of the pathway that can be mutated with patients then becoming resistant to the therapy. Arsenic blocks a different step of the cascade."
Beachy is the senior author of the new findings about arsenic, which will be published online in the Proceedings of the National Academy of Sciences July 12. Jynho Kim, DVM, PhD, a postdoctoral scholar in Beachy's lab, is the first author of the study.
The mechanism of action described by the researchers in the current paper differs from what happens during arsenic poisoning, which occurs when higher levels of the compound choke off a cell's energy production system.
Article continues: http://www.sciencedaily.com/releases/2010/07/100712154428.htm