title: Pilomatrix carcinomas contain mutations in CTNNB1, the gene encoding beta-catenin.
abstract: Mutations in beta-catenin are present in benign pilomatrixomas. beta-catenin is a downstream effector in the WNT-signalling pathway, acting as a signal for differentiation and proliferation. Mutations in CTNNB1, the gene encoding beta-catenin, are present in a wide variety of benign and malignant neoplasms. We examined beta-catenin in a series of pilomatrix carcinomas (15 cases) by using immunohistochemistry and DNA sequencing of exon 3 from CTNNB1, and compared these to a series of benign pilomatrixomas (13 cases). All 11 pilomatrix carcinomas available for examination showed nuclear localization of beta-catenin and mutations in exon 3 similar to those demonstrated in benign pilomatrixomas. Two of 11 pilomatrix carcinomas showed significant nuclear accumulation of p53, whereas this was absent in all 13 benign pilomatrixomas. Expression of nuclear cyclin D1 was similar in both benign pilomatrixomas and pilomatrix carcinomas. Clinical follow-up from the 15 malignant cases reported in this study and by others indicates that wide excision offers superior control of local recurrence, compared to simple excision. Immunohistochemical and molecular analysis of beta-catenin reveals that both pilomatrix carcinomas and benign pilomatrixomas harbour mutations in beta-catenin. This implies a common initial pathogenesis and is compatible with the proposition that pilomatrix carcinomas may at least on occasion arise from their benign counterparts.
authors.affiliation: Department of Pathology, Division of Dermatopathology, Brigham and Women's Hospital, Boston, MA, USA. alazar@mdanderson.org
authors.forename: Alexander J F
authors.initials: AJ
authors.lastname: Lazar
authors.forename: Eduardo
authors.initials: E
authors.lastname: Calonje
authors.forename: Wayne
authors.initials: W
authors.lastname: Grayson
authors.forename: Angelo P
authors.initials: AP
authors.lastname: Dei Tos
authors.forename: Martin C
authors.initials: MC
authors.lastname: Mihm
authors.forename: Mark
authors.initials: M
authors.lastname: Redston
authors.forename: Phillip H
authors.initials: PH
authors.lastname: McKee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism; D002648:Child; D019938:Cyclin D1 / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006201:Hair Diseases / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009154:Mutation; D018296:Pilomatrixoma / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D016133:Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D015534:Trans-Activators / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D051176:beta Catenin
chemical_list: C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D015534:Trans-Activators; D016159:Tumor Suppressor Protein p53; D051176:beta Catenin; D019938:Cyclin D1