A group of promising cancer-fighting compounds derived from the herb wormwood will be developed for potential use in humans, according to researchers at the University of Washington. The compounds make use of a substance known as artemisinin, found in the wormwood plant and used throughout Asia since ancient times to treat malaria.

Researchers became interested in artemisinin about 10 years ago. The chemical helps control malaria because it reacts with the high iron concentrations found in the single- cell malaria parasite. When artemisinin comes into contact with iron, a chemical reaction ensues, spawning “free radicals.” The free radicals attack the cell membrane and other molecules, breaking it apart and killing the parasite.

“Cancer cells need a lot of iron to replicate DNA when they divide,” said scientist Henry Lai.” As a result, cancer cells have much higher iron concentrations than normal cells. When we began to understand how artemisinin worked, I started wondering if we could use that knowledge to target cancer cells.”

Once inside the cancer cell, the iron is released and reacts with the artemisinin. That makes the compound both highly toxic and, because of cancer’s rapacious need for iron, highly selective. Surrounding, healthy cells are essentially undamaged.

Although the compounds are promising, potential medical applications are still years away, officials say.

University of Washington, Oct 14, 2004