ERBB2 and breast cancer: Various bile acids have been reported to have anti-neoplastic and anti-carcinogenic properties in a number of cancer cell models: chenodeoxycholic acid (CDCA) reduced growth of tamoxifen-resistant breast cancer cells by downregulation of human epidermal growth factor receptor 2 (HER2) promoter activity (Giordano et al., 2011), LCA and several of its synthetic enantiomers reduced colon cancer cell proliferation and viability (Katona et al., 2009).