DNA damage response of A549 cells treated with particulate matter (PM10) of urban air pollutants

We describe the events triggered by a sub-lethal concentration of airborne particulate matter (PM10) in A549 cells, which include the formation DNA double-strand breaks, gamma H2A.X generation, and 53BP1 recruitment. To protect the genome, cells activated ATM/ATR/Chk1/Chk2/p53 pathway but, after 48 h, cells turned into a senescence-like state. Trolox, an antioxidant, was able to prevent most of the alterations observed after particulate matter exposure, demonstrating the important role of ROS as mediator of PM10-induced genotoxicity and suggesting that DNA damage could be the mechanisms by which particulate matter augment the risk of lung cancer. (C) 2009 Elsevier Ireland Ltd. All rights reserved.