title: Nuclear localization of beta-catenin involved in precancerous change in oral leukoplakia.
abstract: BACKGROUND
  Oral leukoplakia is a precancerous change developed in the oral mucosa, and the mechanism that oral leukoplakia becomes malignant through atypical epithelium is not known. Here we compared the beta-catenin expression detected by immunohistochemical staining in the normal oral epithelium and in the oral leukoplakia with or without dysplasia.
  
  
  RESULTS
  The normal oral epithelium showed beta-catenin expression only in the cell membrane, but not in the nuclei. In the oral leukoplakia without dysplasia, 7 out of 17 samples (41%) showed beta-catenin expression in the cell membrane, and 5 samples (29%) showed expression in the nuclei. In the oral leukoplakia with dysplasia, nuclear expression of beta-catenin was shown in 11 out of 12 samples (92%). Incidence of nuclear beta-catenin expression was significantly different between dysplasia and normal oral epithelium (P < 0.01), and also between oral leukoplakia with dysplasia and those without dysplasia (P < 0.01). Wnt3 expression was detected in the epithelial cell membrane or cytoplasm in oral leukoplakia where nuclear expression of beta-catenin was evident, but not in epithelial cells without nuclear expression of beta-catenin.
  
  
  CONCLUSIONS
  The components of canonical Wnt pathway, such as Wnt3, beta-catenin, and cyclin D1, were detected, implying that this pathway is potentially involved in the progression of dysplasia in oral leukoplakia.
authors.affiliation: Department of Oral Surgery, Kawasaki Medical School, Kurashiki 701-0192, Japan. kishida@med.kawasaki-m.ac.jp
authors.forename: Kosei
authors.initials: K
authors.lastname: Ishida
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ito
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Wada
authors.forename: Hiroyo
authors.initials: H
authors.lastname: Deguchi
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Hata
authors.forename: Masaru
authors.initials: M
authors.lastname: Hosoda
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nohno
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology; D002467:Cell Nucleus / Q000378:metabolism* / Q000473:pathology; D056741:Cyclin D; D016213:Cyclins / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D007972:Leukoplakia, Oral / Q000378:metabolism* / Q000473:pathology; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000378:metabolism / Q000473:pathology; D011230:Precancerous Conditions / Q000378:metabolism* / Q000473:pathology; D051176:beta Catenin / Q000378:metabolism*
chemical_list: C495270:CTNNB1 protein, human; D056741:Cyclin D; D016213:Cyclins; D051176:beta Catenin