ESR1 and breast neoplasm: Later, it was found that the activation of FXR by CDCA increased cell proliferation and activated estrogen receptor (ER) and estrogen in breast cancer cells, which is in line with the clinical founding that FXR overexpression was significantly correlated with the expression of ER and the proliferation marker Ki-67 in ER-positive breast tumors from postmenopausal women [125].