TFF1 and neoplasm: TFFs are secreted into the gastrointestinal lumen with mucins to protect the mucosal epithelium,28 whereas TFFs also exist in the bloodstream and urine,29, 30 suggesting that TFFs might function not only in a paracrine or autocrine fashion but also in a hormonal fashion, and this study revealed that subcutaneously administered TFF1 significantly suppressed tumor growth in vivo.