title: Infrequent mutations of the p53 gene in pulmonary carcinoid tumors.
abstract: Archival specimens of 25 pulmonary carcinoids including 15 cases of typical carcinoid, 9 atypical carcinoids, and 1 large-cell neuroendocrine carcinoma were analyzed for mutations in exons 5 to 8 of the p53 gene. Mutations were identified in 4 tumors, including 3 out of 15 (20%) typical carcinoids and the single large-cell neuroendocrine carcinoma, but none of the atypical carcinomas showed a mutation. The mutations were acquired during tumor development since they were not present in the corresponding nontumorous tissue. All mutations in the typical carcinoids, a tumor type without epidemiological link to cigarette smoking, were G to A transitions. The level of p53 protein was investigated by immunohistochemistry with the polyclonal antibody CM-1. None of the pulmonary carcinoids investigated showed a positive reaction, despite the presence of missense mutations in two cases. Negative staining of carcinoids with mutations was also observed with the monoclonal antibodies pAb1801 and DO-1. Our data suggest that point mutations of the p53 gene are infrequent in pulmonary carcinoids thus contrasting the findings in other histological types of lung cancer, in particular small-cell lung cancer. Moreover, negative immunostaining for p53 is no indicator for the absence of p53 missense mutations in typical carcinoids.
authors.affiliation: Institute of Pathology, GSF-Forschungzentrum für Umwelt und Gesundheit, Neuherberg, Germany.
authors.forename: D R
authors.initials: DR
authors.lastname: Lohmann
authors.forename: B
authors.initials: B
authors.lastname: Fesseler
authors.forename: B
authors.initials: B
authors.lastname: Pütz
authors.forename: U
authors.initials: U
authors.lastname: Reich
authors.forename: J
authors.initials: J
authors.lastname: Böhm
authors.forename: H
authors.initials: H
authors.lastname: Präuer
authors.forename: P H
authors.initials: PH
authors.lastname: Wünsch
authors.forename: H
authors.initials: H
authors.lastname: Höfler
mesh_terms: D000328:Adult; D000368:Aged; D001483:Base Sequence; D002276:Carcinoid Tumor / Q000235:genetics*; D018288:Carcinoma, Small Cell / Q000235:genetics; D005260:Female; D016158:Genes, p53; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017354:Point Mutation; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
chemical_list: D016159:Tumor Suppressor Protein p53