Dysregulated expression of HS2ST1 is associated with a CSC and metastasis-associated signature in breast cancer cells carrying a mutation in caveolin (Bonuccelli et al., 2009), and upregulation of HS2ST1 is associated with reduced invasive behavior and senescence in breast cancer cells (Kang et al., 2020; Vijaya Kumar et al., 2020). This evidence concerns the gene HS2ST1 and breast cancer.