Recent evidence indicates that breast cancer prognosis is associated with a differential pattern of estrogen receptor (ER) nuclear binding to genes that was determined by a reprogramming of ER binding to these genes by FOXA1 (a FOXO transcription factor); ER and FOXA1 were also found to be co-expressed in samples from metastatic lesions obtained from women with advanced disease [236]. This evidence concerns the gene ESR1 and breast cancer.