PBK and glioblastoma: PBK, a protein related to the mitogen‐activated protein kinase (MAPKK) family, implicated in tumorigenesis of several systemic cancers including breast, prostate and lung cancers (Abe et al., 2000; Brown‐Clay et al., 2015; Park et al., 2006; Shih et al., 2012), is also upregulated in GBM, especially in GBM stem cells (Stangeland et al., 2015).