Small molecule offers hope for cancer treatment
Published Tuesday, January 16, 2007 11:39PM EST
A small, non-toxic molecule may soon be available as an inexpensive treatment for many forms of cancer, including lung, breast and brain tumours, say University of Alberta researchers.
But there's a catch: the drug isn't patented, and pharmaceutical companies may not be interested in funding further research if the treatment won't make them a profit.
In findings that "astounded" the researchers, the molecule known as DCA was shown to shrink lung, breast and brain tumours in both animal and human tissue experiments.
"You typically get this eureka type of feeling. It's the most exciting thing a scientist can get," Dr. Evangelos Michelakis, a professor at the University of Alberta department of medicine and a key study author, told CTV News.
The study was published Tuesday in the journal Cancer Cell.
The molecule appears to repair the damage that cancer cells cause to mitochondria, the units that convert food into energy.
"Cancer cells actively suppress their mitochondria, which alters their metabolism, and this appears to offer cancer cells a significant advantage in growth compared to normal cells, as well as protection from many standard chemotherapies," Michelakis said in a written statement.
As mitochondria regulate cell death, cancer cells can resist being killed off.
For years, DCA -- or dichloroacetate -- has been used to treat children with inborn errors of metabolism due to mitochondrial diseases.
Until recently, researchers believed damage to mitochondria in cancer cells was permanent.
But Michelakis questioned this theory and began testing DCA, which activates a critical enzyme, as a way to "revive" cancer-affected mitochondria.
He says one of the most exciting things about this compound is that it might be able to treat many different forms of cancer because they all suppress mitochondrial function.
Therefore, DCA can primarily affect the cancer cells without affecting the normal ones.
Researchers also say DCA may prove to be effective because it is a small compound, thus easily absorbed in the body.
After oral intake, it can reach areas in the body that other drugs cannot, making it possible to treat cancer of the brain, for example.
In addition, because DCA has been used in both healthy people and ailing patients with mitochondrial diseases, researchers know it is a relatively non-toxic molecule that can be immediately tested in patients with cancer.
The compound, which is sold both as powder and as a liquid, is widely available at chemistry stores.
But because it's not patented or owned by any drug firm, it would be an inexpensive drug to administer. And researchers may have a difficult time finding money for further research.
Dr. Dario Altieri, of the University of Massachusetts, said the drug is exactly what doctors need because it could limit side-effects for patients. But there are "market considerations" that drug companies would have to take into account.
Michelakis remains hopeful he will be able to secure funding for further research.
"We hope we can attract the interest of universities here in Canada and in the United States," said Michelakis.
With a report from CTV's Avis Favaro and Elizabeth St. Philip