CHEK1 and glioblastoma: Interestingly, several studies have demonstrated that DNA damage-induced signaling is enhanced in CSCs of various origins (glioblastoma, NSCLC, head and neck, prostate and pancreas), including increased activation of Chk1, and such cells are particularly sensitive to Chk1-inhibitors (Bao et al., 2006; Bartucci et al., 2012; Venkatesha et al., 2012; Wang et al., 2012; Wu et al., 2012; Fang et al., 2013; Bertrand et al., 2014; Signore et al., 2014).