The activation of DNA damage response upstream regulators, the serine/threonine kinases ATR and ATM, is associated with a reduced load of TMZ-induced DNA double strand breaks and increased TMZ resistance in GBM (Eich et al., 2013), as are mutations in MSH6, a mismatch repair gene (Yip et al., 2009). Here, MARK2 is linked to glioblastoma.