TP53 and osteosarcoma: Furthermore, in another study, SFN was shown to increase ROS levels in a p53-null osteosarcoma (MG-63) as well as bronchial epithelial (BEAS-2B) cell lines where ROS accumulation was accompanied by increased expression levels of Nrf2 and heme oxygenase-1 (OH-1) leading to cell death [43,44].