OLFM4, a glycoprotein belonging to the olfactomedin family, is expressed in stem cells located at the base of intestinal crypts [29] and is associated with colorectal cancers through its colocalization with the G-protein-coupled receptor 5 (Lgr5) on columnar stem cells in the crypt base [30]. The gene discussed is XCR1; the disease is colorectal cancer.