TUSC2 expression is regulated by asbestos and reactive oxygen species. A. TUSC2 is down-regulated by asbestos in mesothelial cell line Met5A and healthy primary culture of mesothelial cells. 1 - non-treated cells; 2 - cells treated with 2.5 μg/cm2 crocidolite asbestos. B. TUSC2 suppression by asbestos is restored upon pre-incubation with reactive oxygen species (ROS) scavengers. Pre-treatment of cells with 500 U/mL catalase (bar 3) or 250 U/mL superoxide dismutase, (SOD) (bar 4) for 30' prior to addition of asbestos to Met5A cells. Data were obtained in triplicates via semi-quantitative RT-PCR and are expressed in percentage change from control (non-treated cells).