NR1H4 and breast cancer: To investigate the critical role of FXR in breast cancer metastasis, immunohistochemistry analysis was performed and the results showed that the immunoreactive score (IRS) of FXR was significantly higher in cancer tissues than in normal tissues, especially in metastatic cancer tissues compared to non-metastatic ones, which indicated that high expression of FXR was correlated to the metastasis of breast cancer (Fig. 2A, B).