title: Caveolin-1 expression in lung carcinoma varies according to tumour histotype and is acquired de novo in brain metastases.
abstract: OBJECTIVE
  To study caveolin-1 (Cav-1) expression in metastatic lung carcinomas.
  
  
  RESULTS
  Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
  
  
  CONCLUSIONS
  Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions.
authors.affiliation: Department of Biomedical Sciences & Oncology, University of Turin, Turin, Italy. paola.cassoni@unito.it
authors.forename: Paola
authors.initials: P
authors.lastname: Cassoni
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Daniele
authors.forename: Elena
authors.initials: E
authors.lastname: Maldi
authors.forename: Luisella
authors.initials: L
authors.lastname: Righi
authors.forename: Veronica
authors.initials: V
authors.lastname: Tavaglione
authors.forename: Silvia
authors.initials: S
authors.lastname: Novello
authors.forename: Marco
authors.initials: M
authors.lastname: Volante
authors.forename: Giorgio Vittorio
authors.initials: GV
authors.lastname: Scagliotti
authors.forename: Mauro
authors.initials: M
authors.lastname: Papotti
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000310:Adrenal Gland Neoplasms / Q000378:metabolism / Q000556:secondary; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D001932:Brain Neoplasms / Q000378:metabolism* / Q000556:secondary; D018287:Carcinoma, Large Cell / Q000378:metabolism* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D051242:Caveolin 1 / Q000235:genetics / Q000378:metabolism*; D004273:DNA, Neoplasm / Q000235:genetics; D018450:Disease Progression; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005784:Gene Amplification / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D051242:Caveolin 1; D004273:DNA, Neoplasm; C512478:EGFR protein, human; D066246:ErbB Receptors