Forty years ago, NG2/CSPG4 proteoglycan (PG) was discovered as a marker of oligodendrocyte precursor cells (OPCs), together with platelet-derived growth factor receptor á (PDGFR-á) in the developing central nervous system (CNS) [1] and CNS cancers such as gliomas [2]. The gene discussed is CSPG4; the disease is central nervous system cancer.