Merlin protein expression was statistically significantly different (P < .05) between groups of different mitotic activity in meningioma (Fig. 1A), as defined by MIB-1 (Ki-67) labeling index (Mitotic index ≥ 4 mitoses/10 HPF and Mitotic index ≥ 20 mitoses/10 HPF) according to the WHO 2016 grading criteria for meningioma.2 We also performed differential expression analysis of Merlin on the basis of the meningioma grade, which classically define aggressive meningiomas. The gene discussed is MKI67; the disease is meningioma.