SMAD4 and breast cancer: KMP was able to reverse the EMT process in gastric, ovarian, and breast cancer cells by increasing E-cadherin expression and reducing the expression of mothers against decapentaplegic homolog 2 (Smad2), mothers against decapentaplegic homolog 4 (Smad4), transforming growth factor-β1 (TGF-β), N-cadherin, vimentin, and Snail [79].