This is the case for UGT2B7 induced by several anti-cancer agents in liver cell models, for UGT2B15 induced by tamoxifen and UGT2B17 induced by exemestane in breast cancer-cell models, as well as for UGT1A4 induced by fulvestrant in breast cancer and liver cell models.42–46. Here, UGT1A4 is linked to breast cancer.