Sci. Trans. Med. 1, 3ra7 (2009)

Blocking a key cell-signalling pathway increases certain tumours' sensitivity to high doses of ionizing radiation while protecting healthy tissue from the harmful rays.

David Roberts of the National Cancer Institute in Bethesda, Maryland, and his colleagues inhibited the cell-surface receptor CD47 or the protein that binds it, TSP1, which regulates cell growth and survival in response to stress, such as that caused by radiation. They found that suppressing the CD47–TSP1 pathway in normal human cells improved their survival after irradiation and, in mice, led to reduced radiation injury.

In addition, the tumours of mice treated with a CD47-blocking molecule prior to radiation exposure were up to 89% smaller 30 days after irradiation than those of mice receiving radiation alone.