FFAR2 and malignant colon neoplasm: The protective effect of butyrate was substantiated in another study that reported a significant downregulation of free fatty acid receptor 2 (FFAR2), a butyrate receptor, in human colon cancer tissues than in healthy tissues, while mice deficient in FFAR2 also developed significantly more colon polyps than wild-type mice (Sivaprakasam et al., 2016).