PTEN and glioblastoma: Collective mutations in tumor suppressor genes PTEN (Wang et al., 1997; Han et al., 2016), TP53 (Dittmer et al., 1993; Nagpal et al., 2006; Zhang et al., 2018), and NF1 (Pearson and Regad, 2017; Soomro et al., 2017; Szopa et al., 2017) are common in primary GBM.