CREB1 and cancer: One group of these cancers is characterized by intra-abdominal epithelial or soft-tissue tumors, where the driver mutation is a fusion between a CREB family member and EWSR1 or FUS [i.e., EWSR1-CREM, FUS-CREM or EWRS1-ATF1 fusions, also called FET-CREB fusions (147–149)].