title: Expression of mesothelioma-related markers in meningiomas: an immunohistochemical study.
abstract: BACKGROUND
  Meningiomas are common intracranial tumors. Recently, histogenetic and phenotypic similarities between meningiomas and mesotheliomas have been proposed. We were interested in whether these similarities are reflected on the immunohistochemical level, which would add new potentially diagnostic markers for meningiomas.
  
  
  METHODS
  The expression of mesothelioma-related markers (D2-40, Calretinin, Keratin 5/6, WT1, and Methotheioma-Ab1) was investigated in 87 cases of meningiomas and compared to EMA expression.
  
  
  RESULTS
  73.6% of meningioma cases were grade I, 20.7% were grade II, and 5.7% were grade III. 83.9% of meningioma cases were classical and 16.1% had special nonmeningothelial features. D2-40 was expressed in 37.9% of cases and was significantly restricted to classical meningiomas. Calretinin and WT1 were negative while Keratin 5/6 and Mesothelioma-Ab1 were weakly expressed in classical variants (5.7% and 3.4%, resp.). EMA was consistently expressed in all cases. Its expression was significantly higher than that of mesothelioma-related markers; this held true also when D2-40 expression was considered separately.
  
  
  CONCLUSIONS
  Mesothelioma-related markers are not extensively expressed in meningiomas, a finding that argues against their proposed histogenetic and phenotypic similarities. Compared to EMA, the significantly lower expression of mesothelioma-related markers and their restricted expression to classical meningioma variants hamper their potential future use as diagnostic markers for meningioma.
authors.affiliation: Department of Pathology, Faculty of Medicine, University of Alexandria, Alexandria 21533, Egypt.
authors.forename: Eman
authors.initials: E
authors.lastname: Abdelzaher
authors.affiliation: Department of Pathology, Faculty of Medicine, University of Alexandria, Alexandria 21533, Egypt.
authors.forename: Dina Mohamed
authors.initials: DM
authors.lastname: Abdallah
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008579:Meningioma / Q000378:metabolism* / Q000473:pathology*; D008654:Mesothelioma; D008875:Middle Aged
chemical_list: D014408:Biomarkers, Tumor