CADM3 (cell adhesion molecule 3) is a calcium-independent cell adhesion protein mediating both homophilic and heterophilic cell-cell adhesion interactions 1. In the peripheral nervous system, CADM3 functions as the primary axonal ligand for glial Cadm4, where it regulates myelinated axon organization and the distribution of ion channels like Kv1 potassium channels; this interaction can be partially compensated by Cadm1 and Cadm2 1. CADM3 is associated with Charcot-Marie-Tooth disease, axonal type 2FF, a hereditary motor neuropathy where CADM3 mutations were identified through whole exome/genome sequencing as causative genetic factors 2. Beyond neurological functions, CADM3 serves as a biomarker in multiple contexts: it is significantly correlated with colorectal cancer prognosis 3, is downregulated in amyotrophic lateral sclerosis cerebrospinal fluid suggesting neuropathological significance 4, and is highly expressed in superficial CD34-positive fibroblastic tumors where it aids diagnostic classification 5. In fibroblast biology, CADM3 participates in a regulatory axis controlling collagen I synthesis and skin thickness through AKT/ERK pathway activation 6. Additionally, CADM3 suppression by miR-140-5p inhibits retinoblastoma cell proliferation and invasion 7, indicating tumor-suppressive potential in certain cancer contexts.