Trefoil Factor 2 (TFF2), also known as spasmolytic peptide (SP), is one of three structurally related secreted proteins that contain trefoil domains. Trefoil factor 2 belongs to the trefoil factor family that consists of three members named TFF1, TFF2 and TFF3. They are characterized by having at least one copy of the trefoil motif, a 40-amino acid domain that contains three conserved disulfides. Mature human TFF2 shares 87% and 83% amino acid sequence identity with mouse and rat TFF2. The TFFs are stable secretory proteins expressed highly in the gastrointestinal tract (gastric mucosa). TFF2 can inhibit gastrointestinal motility and gastric acid secretion. Additionally, it functions as a structural component of gastric mucus, possibly by stabilizing glycoproteins in the mucus gel through interactions with carbohydrate side chains. Administration of TFF2 can reduce the severity of experimental colitis. TFF2 is down-regulated in many gastric cancers, although it is up-regulated in some breast cancers.