BCL9 and meningioma: FOXM1 is an unexpected but key mediator of the Wnt/β-catenin signaling as it binds to β-catenin, thus enhancing β-catenin nuclear localization and transcriptional activity.15,16 Several studies suggested that TCF/LEF and β-catenin coactivators, such as Pygopus/Bcl9, mediate β-catenin nuclear import or retention/anchoring.43 In the present study, we systematically analyzed the Merlin expression patterns in meningioma cell lines and tumor specimens.