Effect of Nrf2 in tumor progression and its inhibitors in cancer therapy

Nrf2 is the key transcription factor mainly for regulating oxidative homeostasis and cytoprotective responses against oxidative stress. Nrf2/Keap1 pathway is one of the most important cellular defense mechanisms against endogenous or exogenous oxidative stress. With its activation, a wide range of stress-related genes is transactivated to restore the cellular homeostasis. Recent studies revealed that the aberrant activation of Nrf2 is related to the malignant progression, chemotherapeutic drug resistance and poor prognosis. Nrf2 plays a crucial role in cancer malignancy and chemotherapeutic resistance by controlling the intracellular redox homeostasis through the activation of cytoprotective antioxidant genes. Nrf2 inhibitor containing many natural products has been deemed as a novel therapeutic strategy for human malignancies. This article reviews the progress of studies of the Nrf2/Keap1 pathway, and its biological impact in solid malignancies and molecular mechanisms for causing Nrf2 hyperactivation in cancer cells. In conclusion, we summarized the deve-lopment of Nrf2 inhibitors in recent years, in the expectation of providing reference for further drug development and clinical studies.