KEAP1 and neoplasm: Indeed, increased expression and activity of NRF2, resulting from mutations in KEAP1 and/or NRF2, have been observed in various tumor cells, including skin, breast, prostate, lung, head/neck, and endometrium (Kim et al. 2010; Ohta et al. 2008; Padmanabhan et al. 2006; Shibata et al. 2008; Singh et al. 2006; Stacy et al. 2006).