OLFM4 and inflammatory bowel disease: Olfactomedin-4 (Olfm4) is a glycoprotein gene studied mostly in relation to the digestive system pathologies; in gastrointestinal malignancies, it has a role as an antiapoptotic factor, in Helicobacter pylori infection it downregulates innate immunity through the negative feedback on the NF-κB pathway, whereas in the inflammatory bowel diseases it affects the anti-inflammatory function (Wang et al., 2018).