Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor which belongs to the Cap N Collar (CNC-bZIP) subfamily with an implication in adaptive responses to oxidative stress. Nrf2 is a basic leucine zipper transcription factor that can bind to a NF-E2/AP-1 repeat sequence in the promoter of the beta-globin gene and has two types of binding partners, a cytoplasmic repressor (Keap I) and multiple nuclear binding partners. During oxidative stress on a cell, Nrf2 is released from Keap I, possibly via PKC phosphorylation at serine 40, and translocates to the nucleus. In the nucleus, Nrf2 binds to antioxidant responsive element (ARE) and leads to transcriptional activation of downstream genes for GSTs, glutamate-cysteine ligase, HO-1, and thioredoxin. Nrf2 and its downstream proteins have shown to have important functions in protection against oxidative stress or chemical-induced cellular damage in liver and lung, prevention in cancer formation in GI tract, and promotion of the wound-healing process.