MKI67 and glioblastoma: To investigate the distribution of proliferative cells across spatially distinct GBM regions, Ki-67 immunohistochemistry (IHC) was performed on tissue sections from GBM patients (N = 36), revealing a high number of proliferative cells in the Core superficial medial region (Fig. 1J) followed by anterior medial (Fig. 1K) and Rim regions (Fig. 1L).