• Journal of Korean Neurosurgical Society
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• v.30 no.sup1
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• pp.140-143
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• 2001

We report a case of huge trigeminal schwannoma in a 10-year-old boy with neurofibromatosis type II, extending into the three spaces of the left middle, posterior, and infratemporal fossa. Initially we thought the child had a solitary trigeminal schwannoma, and most of the mass was resected successfully through one-stage operation, cranio-orbito-zygomatic intradural approach. However during the follow-up of the patient we found radiographically other multiple intracranial tumors of bilateral acoustic schwannomas, right trigeminal schwannoma, and foramen magnum tumor. Eventually the patient was diagnosed as neurofibromatosis type II presenting multiple intracranial tumors. We think childhood trigeminal schwannoma, even though in the case of solitary tumor, should be considered as possible initial manifestation of neurofibromatosis type II and that careful follow-up for the possibility of occurrence of other brain tumors such as schwannomas or meningiomas is necessary.

• Korean Journal of Bronchoesophagology
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• v.11 no.2 s.22
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• pp.36-39
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• 2005

Neurofibromatosis type II is an autosomal dominant, highly penetrant disease whose hallmark is bilateral vestibular schwannoma. Hearing loss is the most symptom in Neurofibromatosis type II. The patient can also present with tinnitus, disequilibrium, and headache. Cranial nerve symptoms, such as facial numbness or weakness, dysphagia, or hoarseness, can also be present. The authors experienced a case of neurofibromatosis type II having huge retropharyngeal mass, retropharyngeal abscess, and bilateral acoustic neuromas. The infection was controled with aggressive antibiotics with drainage. The huge neurilemmoma in retropharyngeal space was removed successfully via transoral approach. The authors report the case with literature review.

• BMB Reports
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• v.49 no.7
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• pp.357-358
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• 2016

Merlin, encoded by the NF2 gene, is a tumor suppressor that exerts its function via inhibiting mitogenic receptors at the plasma membrane. Although multiple mutations in Merlin have been identified in Neurofibromatosis type II (NF2) disease, its molecular mechanism is not fully understood. Here, we show that Merlin interacts with LRP6 and inhibits LRP6 phosphorylation, a critical step for the initiation of Wnt signaling. We found that treatment of Wnt3a caused phosphorylation of Merlin by PAK1, leading to detachment of Merlin from LRP6 and allowing the initiation of Wnt/β-catenin signaling. A higher level of β-catenin was found in tissues from NF2 patients. Enhanced proliferation and migration caused by knockdown of Merlin in glioblastoma cells were inhibited by suppression of β-catenin. Conclusively, these results suggest that sustained Wnt/β-catenin signaling activity induced by abrogation of Merlin-mediated inhibition of LRP6 phosphorylation might be a cause of NF2 disease.