Horseshoe conformations are also found for the N-terminal four Ig domains of a number of other IgSF molecules including all members of the deleted in colorectal cancer (DCC), CNTN, L1, Dscam, cell adhesion associated oncogene regulated (CDON), MAM domain–containing glycosylphosphatidylinositol anchors (MDGA), and activated leukocyte cell adhesion molecule (ALCAM) families (Chen et al., 2013). Here, ALCAM is linked to colorectal cancer.