NFE2L2 and cancer: In contrast, NRF2 was reported to transcriptionally activate the expression of proteasome subunit genes in a few cancers, including colon and breast cancer [91,92], and it was also demonstrated to be an activator of proteasome subunit genes in cells treated with electrophiles, such as sulforaphane and 3H-1,2-dithiole-3-thione [93].