title: Craniopharyngiomas of adamantinomatous type harbor beta-catenin gene mutations.
abstract: Craniopharyngioma is a rare tumor occurring in the sellar region comprising 3% of all intracranial tumors. To elucidate the contribution of beta-catenin gene mutation to tumorigenesis, we examined genetic alterations and expression of beta-catenin in 10 cases of adamantinomatous and 6 cases of papillary craniopharyngiomas. Beta-catenin gene mutations were found in all of the adamantinomatous and none of the papillary craniopharyngiomas. Immunohistochemically, all cases of adamantinomatous craniopharyngioma showed cytoplasmic and nuclear expression of beta-catenin. In contrast, papillary craniopharyngiomas showed exclusively membranous expression. The results suggest that adamantinomatous- and papillary-type craniopharyngiomas are not only clinicopathologically, but also genetically, distinctive variants. Mutation of the beta-catenin gene therefore seems to play an important role in the tumorigenesis of adamantinomatous craniopharyngioma. Among the adamantinomatous-type tumors, beta-catenin-positive mesenchymal cells were observed in two cases. Microdissection-based mutational analysis revealed that these mesenchymal cells also harbor the same beta-catenin gene mutations as those of epithelial cells, suggesting their tumorous nature. Thus, at least a subset of adamantinomatous craniopharyngioma is considered to be biphasic.
authors.affiliation: Pathology Division, National Cancer Center Research Institute, 5-1-1 Tsukuji, Chuo-ku, Tokyo 104-0045, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sekine
authors.forename: Tatsuhiro
authors.initials: T
authors.lastname: Shibata
authors.forename: Akiko
authors.initials: A
authors.lastname: Kokubu
authors.forename: Yukio
authors.initials: Y
authors.lastname: Morishita
authors.forename: Masayuki
authors.initials: M
authors.lastname: Noguchi
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Nakanishi
authors.forename: Michiie
authors.initials: M
authors.lastname: Sakamoto
authors.forename: Setsuo
authors.initials: S
authors.lastname: Hirohashi
mesh_terms: D000328:Adult; D002648:Child; D002675:Child, Preschool; D003397:Craniopharyngioma / Q000235:genetics* / Q000473:pathology; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D015534:Trans-Activators / Q000235:genetics*; D051176:beta Catenin
chemical_list: C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D004273:DNA, Neoplasm; D015534:Trans-Activators; D051176:beta Catenin