MAPK9 and neoplasm: Ten of the fourteen genes (DVL1, PRKACB, APC, MAPK9, CAMK2A, CACNA1A, ERBB4, NF1, MAPK8IP2, and PPM1A) were mainly expressed by oligodendrocyte progenitor cells (OPCs) located in the tumor margin, as determined through single-cell sequencing data analysis (Table 3).