CSPG4 (Chondroitin sulfate proteoglycan 4, MCSP, NG2) is a transmembrane proteoglycan that functions in angiogenesis, cell survival and migration, and the modulation of neuronal networks and pericyte functions. CSPG4 is an important prognostic marker in cancer, as it is upregulated in glioblastoma and is expressed on the cell surface of malignant melanoma cells, where it is involved in progression and spreading. In normal tissue, CSPG4 is highly expressed on NG2-glia cells in the brain, and is also found on osteoblasts, melanocytes, smooth muscle cells, mesenchymal stem cells, and pericytes. It is also a useful marker for oligodendrocyte precursor cells in developing and adult humans. Mutations in CSPG4 can result in a disruption in white matter integrity and oligodendrocyte morphology in the brain and are correlated with familial schizophrenia. In immunohistochemistry, CSGP4 has membranous and cytoplasmic positivity in all tissues throughout the body. References: Cellular & Molecular Biology Letters. 2017. 22(4), PMID: 28536635; Int J Mol Sci. 2018 Sep; 19(9): 2724, PMID: 30213051; Mol Psychiatry. 2019 May;24(5):757-771, PMID: 29302076