For example, CDO1 expression was preferably silenced due to hypermethylated promoter in NSCLC cells with KEAP1 mutation, thereby protecting cells from oxidative damages through NRF2-mediated antioxidant defense; while its restoration remarkably antagonized the viability in NSCLC cells by producing toxic sulfur-based chemicals or depleting intracellular NADPH [19]. Here, KEAP1 is linked to non-small cell lung carcinoma.