HMOX1 and cancer: The mutp53-activated NRF2 target gene signature is associated with poor patient prognosis in breast cancer, and includes genes with pro-survival function, such as thioredoxin (TXN); in contrast, mutp53 represses other NRF2 targets including heme oxygenase 1 (HMOX1), which have been shown to display cytotoxic effects in cancer cells, although being cytoprotective in untransformed cells [46].