Direct damage from radiation may be passed to neighboring cells

Cells communicate, organize, share resources, and form direct connections with one another. They also are affected by damage to their neighbors. Research led by John Little of the Harvard School of Public Health shows that cells hit by radiation can send signals to neighboring cells that result in DNA damage. These findings challenge the long-held assumption that radiation harms cells only by direct contact, suggesting that radiation’s biological effects are more complex than previously thought. In 1992, Little’s lab first published evidence that given a population of cells in which only an occasional cell is irradiated, biological effects associated with radiation damage can occur in nonirradiated, or bystander, cells. “This is really quite a new concept,” said Little. “In fact, at first no one really believed it.”