CD8A and glioblastoma: The E2F6 expression was remarkably positively related to tumor purity (r = 0.316, P = 3.66e − 11), CD8+ T cells (r = 0.187, P = 1.25e − 04), and macrophages (r = 0.192, P = 8.08e − 05) but no significant correlation with neutrophils (r = 0.145, P = 2.90e − 03) in GBM (Figure 7(f)).