NFE2L2 and adenocarcinoma: While NRF2 protein levels are highly inducible in normal cells in response to oxidative and xenobiotic stress or electrophile exposure, constitutive NRF2 expression is observed in several cancers [3,4,5,6,7,8], including the squamous and adenocarcinoma subtypes of non-small cell lung cancer (NSCLC) [3], and squamous cancers of the esophagus, skin, larynx, and other tissues [6].