They characterised the expression of TAS2R1, TAS2R4, TAS2R10, TAS2R38 and TAS2R49 in those cells, finding that TAS2R4 is expressed at 40–70% in mammary epithelial cells in comparison to the commonly used breast cancer marker proteins, estrogen receptor and E-cadherin. Here, TAS2R4 is linked to breast cancer.