Endocrine Abstracts

As a phytoestrogen, kaempferol plays a chemopreventive role inhibiting cancer formation and progression. In this study, chemopreventive activity of kaempferol was examined by measuring its effect on growth, epithelial-mesenchymal transition (EMT), and migration of MCF-7 breast cancer cells increased by 17β-estradiol (E2, a positive control) or triclosan (TCS), an endocrine-disrupting chemical (EDC). As an EDC, TCS is known to interfere estrogen receptor (ER) dependent pathway in MCF-7 cells expressing ERs. In MTT assay, TCS (10⁻⁴–10⁻⁷ M) or E2 (10⁻⁹ M) induced cell growth of MCF-7 cells, which was reversed to a control level by co-treatment of ICI 182,780 (10⁻⁸ M), an ER antagonist, or kaempferol (50 uM). In a wound-healing scratch assay, TCS enhanced migration of MCF-7 cells like E2, but co-treatment of kaempferol or ICI 182,720 decreased the migration ability of MCF-7 cells to a control level. In RT-PCR and western blot assay, we examined the effect of TCS and DIM on mRNA and protein expression of EMT-related markers such as E-cadherin, N-cadherin, snail and slug. TCS induced the increased expression of EMT promoting markers such as N-cadherin, snail and slug but down-regulated the expression of E-cadherin, an epithelial marker inhibiting EMT process. On the contrary, kaempferol was shown to reverse the expression pattern of EMT-related markers induced by TCS or E2. In conclusion, kaempferol effectively suppressed growth, EMT, and migration ability of MCF-7 breast cancer cells increased by E2 and TCS.