a, Meningioma DNA methylation analysis of chromosome 22q segment copy number deletions of any size containing the entire NF2 locus across Merlin-intact (n=32 of 192 meningiomas, 17%), Immune-enriched (n=165 of 216 meningiomas, 76%), and Hypermitotic (n=154 of 157 meningiomas, 98%) DNA methylation groups (n=565, Chi-squared test, two-sided). b, Meningioma NF2 transcripts per million (TPM) expression across Merlin-intact (n=72), Immune-enriched (n=65), and Hypermitotic (n=63) DNA methylation groups (n=200, ANOVA, one-sided). c, Immunoblot for Merlin or GAPDH in 3 meningiomas with loss of at least one copy of the NF2 locus from each meningioma DNA methylation group. d, Confocal microscopy and quantification of Annexin V in M10GdCas9-KRAB cells stably expressing a non-targeting control single-guide RNA (sgNTC) or a single-guide RNA suppressing NF2 (sgNF2) after 24 hours of actinomycin D or vehicle control treatment. DNA is marked with DAPI. Scale bar 10 μM. From left to right, 53, 88, 69, or 56 cells are shown (ANOVA, one-sided). e, Immunoblot for FLAG, cleaved Caspase-7 (cCaspase-7), or GAPDH from CH-157MN xenografts stably expressing doxycycline-inducible Merlin encoding a FLAG tag (NF2-FLAG) in NU/NU mice after 7 days of doxycycline or vehicle treatment, and 24 hours after 4 Gy ionizing radiation or control treatment. f, Immunoblot for ARHGAP35 or FLAG after FLAG immunoprecipitation from CH-157MN cells stably expressing Merlin encoding a FLAG tag (NF2FLAG). EV, empty vector. g, QPCR for NF2 or NR3C1 in M10GdCas9-KRAB cells stably expressing sgNTC, sgNF2, or sgNF2 with NF2 rescue (sgNF2+NF2HA). 3 biological replicates per condition (Student’s t test, one-sided). h, Quantification of Annexin V confocal microscopy in IOMM-Lee cells stably expressing a short-hairpin RNA suppressing NF2 (sgNF2-2) and transiently expressing a non-targeting control siRNA (siNTC) or siRNAs suppressing NR3C1 (siNR3C1). Cells were treated as in d. From left to right, 39, 80, 58, or 52 cells are shown (ANOVA, one-sided). i, NR3C1 TPM expression in euploid meningiomas (n=52) or meningiomas with loss of NF2 as the only CNV (n=28) (Student’s t test, one-sided). j, Model of Merlin pro-apoptotic tumor suppressor function in meningioma cells. Lines represent means, and error bars represent standard error of the means. ***p≤0.0001.