Cancer stem cells from breast tumours have lower levels of reactive oxygen species (ROS) than other cell types from the same tumour. The finding, reported online in Nature, may explain why breast cancer often becomes resistant to radiation therapy.
It's known that ionizing radiation prompts cells to release ROS, causing cell damage. Michael Clarke and colleagues found that breast cancer stem cells are relatively resistant to ionizing radiation both in vivo and in vitro. This may be because the cells generate low levels of ROS and develop less DNA damage than other cell types within the same tumour. Indeed human breast cancer stem cells also show the increased expression of several important anti-ROS genes previously shown to mediate radioresistance.
Michael Clarke (Stanford University, Palo Alto, CA, USA)
Abstract available online.
(C) Nature press release.
Message posted by: Trevor M. D'Souza