DURHAM, N.C., May 28 (UPI) -- U.S. and British scientists say stem cells that respond after a severe injury in the lungs of mice may produce rapidly dividing cells that cause lung cancer.
"There are chemically resistant, local-tissue stem cells in the lung that only activate after severe injury," Duke University Medical Center Professor Barry Stripp said. "Cigarette smoke contains a host of toxic chemicals, and smoking is one factor that we anticipate would stimulate these stem cells. Our findings demonstrate that, with severe injury, the resulting repair response leads to large numbers of proliferating cells that are derived from these rare stem cells."
Stripp said the finding could be related to the increased incidence of lung cancer in people with chronic disease states, in particular among cigarette smokers.
"On the positive side, I think that it might be possible to improve lung function in the context of disease if we could understand which pathways regulate lung stem cell activation and then target these pharmacologically," said lead author Adam Giangreco of the organization Cancer Research UK. "In terms of lung cancer susceptibility, however, our observation that stem cell activation leads to clonal expansion after injury could, in the context of additional mutations, promote the development of cancerous or precancerous lesions from activated stem cells."
The findings appear in the early online edition of the Proceedings of the National Academy of Sciences.