Using singleR and manual annotation based on marker genes, we classified cells into four subpopulations: immune cells (identified by markers CD14, FCGR1A, MSR1, and CD163), oligodendrocytes (identified by markers OLG2, FA2H, UGT8, and CNP), astrocytes (identified by marker GFAP), and cancer cells (identified by markers PARP1, CD44, and IFAP) (Fig. 1G–I). Here, PARP1 is linked to cancer.