Cabbage Juices and Indoles Modulate the Expression Profile of AhR, ERα, and Nrf2 in Human Breast Cell Lines

Abstract

Our previous studies showed the diversified effect of cabbage juices and indoles on the estrogen metabolism key enzymes (CYP1A1, CYP1A2, CYP1B1) in breast epithelial cells differing in ER status, i.e., in tumorigenic—MCF7, MDA-MB-231 and non-tumorigenic—MCF10A cells. The aim of the present study was to further investigate the mechanism of chemopreventive action of cabbage juice and its active components by evaluating their effect on the expression of AhR, ERα, and Nrf2 using the same treatment regimen. The mRNA level of AhR and ERα was changed in a cell type-dependent manner and in general correlated with previously observed modulation of CYP expression. However, in most cases the alterations in mRNA were not accompanied by the changes in the level of relevant proteins. Marked differences were also found in the effect of cabbage juices and indoles; although both cabbage juices and indoles increased most of the NQO1 transcript levels in all tested lines, indoles also enhanced GSTP transcription in MCF7 and MDA-MB-231. Overall, the results of this study partly explain the mechanism behind the chemopreventive activity of white cabbage products and indicate that modulation of the expression of specific transcription factors may play an important role in this process.