SERPINE2 and cancer: The A2B5+, BRAF+ population was marked by high levels of canonical markers of PA cancer cells, including oligodendrocyte-associated markers (OLIG1, OLIG2, PDGFRA), glial markers (GFAP, APOD, APOE), serine proteases (SERPINA3, SERPINE2), and other PA markers such as PLEKHB1. At pathway level, gene set enrichment analysis (GSEA) revealed enrichment of gene signatures associated with CNS tumors (n = 16) or normal CNS cell types such as neurons, oligodendrocytes, or astrocytes (n = 15) (Supplementary Data 5).