It's reported that many factors can regulate FUT8 expression, such as microRNA (Bernardi et al., 2013) and selective inhibitor of Src tyrosine kinases (Kaminska et al., 2008), etc. However, whether fentanyl could upregulate the FUT8 and α1, 6-fucosylation level, and further influence stemness and EMT in breast cancer is yet to be elucidated. Here, FUT8 is linked to breast cancer.