Stem-cell-protecting drug could prevent the harmful side effects of radiation therapy

September 6, 2012

Radiation therapy is one of the most widely used cancer treatments, but it often damages normal tissue and can lead to debilitating conditions. A class of drugs known as mammalian target of rapamycin (mTOR) inhibitors can prevent radiation-induced tissue damage in mice by protecting normal stem cells that are crucial for tissue repair, according to a preclinical study published by Cell Press in the September issue of the journal Cell Stem Cell.

"We can exploit the emerging findings for the development of new preventive strategies and more effective treatment options for patients suffering this devastating disease," says senior study author J. Silvio Gutkind of the National Institute of Dental and Craniofacial Research.

In response to , cancer patients often develop a painful condition called mucositis—tissue swelling in the mouth that can leave these patients unable to eat or drink and force them to rely on opioid-strength . Radiation therapy may cause this debilitating condition by depleting normal stem cells capable of repairing damaged tissue.

In the new study, Gutkind and his team found that the mTOR inhibitor rapamycin protects stem cells taken from the mouths of healthy individuals (but not ) from radiation-induced death and DNA damage, dramatically extending the lifespan of these normal stem cells and allowing them to grow. Rapamycin exerted these protective effects by preventing the accumulation of harmful molecules called reactive . Moreover, mice that received rapamycin during did not develop mucositis.

Because rapamycin is approved by the and is currently being tested in clinical trials for the prevention and treatment of various types of cancer, the new findings could have immediate and important implications for a large proportion of cancer patients. "Mucositis prevention would have a remarkable impact on the quality of life and recovery of cancer patients and at the same time would reduce the cost of treatment," Gutkind says. "Our study provides the basis for further testing in humans, and we hope that these findings can be translated rapidly into the clinic."

More information: Iglesias-Bartolome et al.: "mTOR inhibition prevents epithelial stem cell senescence and protects from radiation-induced mucositis." DOI:10.1016/j.stem.2012.06.007

Finkel et al.: "Relief with Rapamycin: mTOR Inhibition Protects against Radiation-Induced Mucositis"(In Translation Article)

Related Stories

Study reveals how cancer drug causes diabetic-like state

April 3, 2012

Scientists at Dana-Farber Cancer Institute have discovered why diabetic-like symptoms develop in some patients given rapamycin, an immune-suppressant drug that also has shown anti-cancer activity and may even slow ageing.

Recommended for you

Study reveals new insight into DNA repair

August 3, 2015

DNA double-strand breaks (DSBs) are the worst possible form of genetic malfunction that can cause cancer and resistance to therapy. New information published this week reveals more about why this occurs and how these breaks ...

Strange circular DNA may offer new way to detect cancers

July 30, 2015

Strange rings of DNA that exist outside chromosomes are distinct to the cell types that mistakenly produced them, researchers have discovered. The finding raises the tantalizing possibility that the rings could be used as ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.