CADM4 (Cell adhesion molecule 4, IGSF4C, TSLL2) is a membrane glycoprotein of the immunoglobulin superfamily. It is involved in cell-cell interaction, adhesion, regulation of contact inhibition and proliferation. It is expressed in glia and axons, where it functions in Schwann cell and axon interaction. It is also important for the development of the myelin unit in the peripheral nervous system, and absence of CADM4 leads to myelin abnormalities akin to those in Charcot-Marie-Tooth syndrome. CADM4 is thought to be involved in tumor suppression, and expression is lost in breast carcinomas, prostate carcinomas, renal carcinomas and gliomas. In immunohistochemistry, CADM4 has highest cytoplasmic and membranous positivity in neurons in the cerebral cortex, followed by positivity in cell-cell attachment sites in proximal renal tubules, the glandular epithelia of the prostate, the transitional epithelia of the bladder, and a few additional tissues. References: PLoS One. 2015; 10(4): e0124259, PMID: 25893857; Oncogene. 2006 Mar 9;25(10):1446-53, PMID: 16261159; Int J Cancer. 2012 Mar 15;130(6):1329-37, PMID: 21544807; Oncol Lett. 2018 Feb; 15(2): 2401–2406, PMID: 29434950; J Neurosci. 2013 Jul 3;33(27):10950-61, PMID: 23825401