Thus, we hypothesized that overexpression of Brf2, which is also observed in many forms of cancer (Cabarcas and Schramm, 2011), is required to overcome the Brf2-dependent reduction of SeCys tRNAs observed during prolonged oxidative stress, in order to maintain sufficient expression levels of selenoproteins required for ROS detoxification and redox homeostasis. Here, SELENOS is linked to cancer.