Consistent with prior work demonstrating MEK inhibitor efficacy selectively against NF1-mutant glioblastoma (35, 36), in vitro cell viability analysis showed that NF1-mutant glioblastoma cells were significantly more sensitive to selumetinib compared with NF1 wild-type glioblastoma cells (Supplemental Figure 9). This evidence concerns the gene MAP2K7 and glioblastoma.