"This work may open up therapeutic avenues for people who need radiation treatment," said Michelle Monje, an MD/PhD student and first author on the paper. The work, led by Theo Palmer, PhD, assistant professor of neurosurgery, and co-authored by postdoctoral scholar Hiroki Today, MD, PhD, will be published in the Nov. 14 advance online issue of the journal Science and in the Dec. 5 print edition.
People with brain tumors and leukemia often receive radiation therapy to destroy cancerous cells. But that treatment also damages healthy brain cells - in particular those cells in the memory center of the brain, called the hippocampus. This damage leads to serious problems with memory and learning. Memory loss is especially noticeable in children who undergo whole-brain radiation, the majority of whom end up in special education classes after the procedure, according to Monje.
Doctors had hoped that implanting brain stem cells - cells that reside in the brain and can form into any brain cell type - could replace the lost neurons. But those relief worker cells rarely flourish in their transplanted home. "They are still there, but they can't do their job," Monje said. "Something was wrong in the environment where the stem cells should be making neurons."
Monje and Palmer suspected the culprit might be inflammatory cells that rush to the site of radiation or injury-induced damage. This idea arose in part because people with Alzheimer's disease or other forms of dementia associated with brain inflammation often fare better when they receive a group of drugs called nonsteroidal anti-inflammatory drugs, or NSAIDs, that foil infla
Contact: Amy Adams
Stanford University Medical Center