GFAP and neoplasm: Immunostaining for GFAP, CD45, and Ki67 protein expression enabled the segmentation and isolation of 34 segments representing tumor cells (T, GFAP+), 10 segments representing proliferating tumor cells (K, GFAP+Ki67+), and 20 segments representing immune cells (I, CD45+) using digital spatial profiling on the NanoString GeoMx platform (Table 2, Supplementary Tables S1 and S2).