In tumor microenvironment, Nrf2 is activated by tumor suppressor genes BRCA1 and protein p21 via the inhibition of Keap1/Nrf2 complex formation59, 60 and is blocked by oncogene Fyn‐mediated degradation.61 The expression of antioxidant and phase II enzymes was found to be abrogated in the Nrf2‐deficient mice. This evidence concerns the gene BRCA1 and neoplasm.