title: Claudin expression is dysregulated in prostate adenocarcinomas but does not correlate with main clinicopathological parameters.
abstract: OBJECTIVE
  Claudins, a large family of essential tight junction (TJ) proteins, are abnormally regulated in human carcinomas. The aim of this study was to determine the expression of claudins 1, 2, 3, 4, 5, 7, and 11 in prostate samples from Brazilian patients and correlate it with the clinicopathological features of prostate cancer.
  
  
  METHODS
  Using a tissue microarray (TMA) of specimens of prostate adenocarcinoma and benign prostatic hyperplasia (BPH) we analysed the expression of claudins 1, 2, 3, 4, 5, 7, and 11 by immunohistochemistry.
  
  
  RESULTS
  Claudin 4 was down-regulated and claudins 2, 3, and 5 were overexpressed in prostate adenocarcinomas compared with BPH samples. Expression of claudins 1 and 7 was similar in tumours and BPH samples. Claudin 11 was absent from all prostate samples. Overexpression of claudin 3 was associated with perineural invasion (p = 0.014) and tended to occur in advanced stages of the disease (p = 0.064). Increased expression of claudin 5 was marginally associated with perineural invasion (p = 0.060).
  
  
  CONCLUSIONS
  Our results suggest that alterations in claudin expression occur in prostate cancer cells, although we have not found an association with the main clinicopathological parameters.
authors.affiliation: Department of Anatomic Pathology, Hospital A. C. Camargo, São Paulo, Brazil. claumcc@terra.com.br
authors.forename: Cláudia Malheiros
authors.initials: CM
authors.lastname: Coutinho-Camillo
authors.forename: Silvia Vanessa
authors.initials: SV
authors.lastname: Lourenço
authors.forename: Francisco Paulo
authors.initials: FP
authors.lastname: da Fonseca
authors.forename: Fernando Augusto
authors.initials: FA
authors.lastname: Soares
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000556:secondary; D014408:Biomarkers, Tumor / Q000378:metabolism; D057167:Claudins / Q000378:metabolism*; D015536:Down-Regulation; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011468:Prostatectomy; D011470:Prostatic Hyperplasia / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; D057167:Claudins