TFF2 and cancer: Elevated expression of SP/NK-1R has been identified in multiple cancer types and promotes angiogenesis, proliferation, and metastasis of solid tumor cells, including breast (9, , , –13), gastric (14, 15), liver (16, –18), colon (19), and pancreatic (20, –22) cancer, as well as melanoma (23), in an autocrine, paracrine, or neurocrine manner.