PDGFRA and neoplasm: We sorted tumor OPCs by flow cytometry based on their surface expression of PDGFRα (Figure 1L,M), and validated that PDGFRα high expression fraction not only enriched the tumor cells growing in nonadherent culture condition (Figure 1N), but also those more effectively initiating secondary tumors after orthotopically grafted in the NOD‐SCID mouse brains (Figure 1O).