CHEK2 and glioblastoma: In addition, the co-expression of APEX1 and CHEK2 genes was positively correlated in the TCGA glioblastoma data set (r = 0.198, p = 3.6.10–6, n = 540; Tumor Glioblastoma-TCGA-540-MAS5.0-u133a dataset; R2: Microarray Analysis and Visualization Platform).