CREB1 and breast carcinoma: The negative correlation between miR-27b and NR5A2 and CREB1 expression has further been corroborated in human breast cancer tissues from tamoxifen-untreated and tamoxifen-resistant patients, suggesting that miR-27b may be a predictive marker for tamoxifen responsiveness, as well as a potential therapeutic target to overcome tamoxifen resistance [67].