title: Unique expression pattern of the EMT markers Snail, Twist and E-cadherin in benign and malignant parathyroid neoplasia.
abstract: BACKGROUND
  Epithelial and mesenchymal transitions (EMT) are essential for embryonic development and progression of non-invasive tumor cells into malignant, metastatic carcinomas. During embryogenesis, the parathyroid glands develop from pharyngeal pouches and migrate to their final destinations, densely enclosed by mesenchymal neural crest cells. In this study, we examined the expression of the EMT markers Snail, Twist and E-cadherin in normal parathyroid glands and benign and malignant parathyroid diseases.
  
  
  METHODS
  Using immunohistochemistry, we compared expression of E-cadherin, Snail and Twist in 25 patients with parathyroid adenoma, 25 patients with parathyroid hyperplasia, and nine patients with parathyroid cancer with normal parathyroid glands.
  
  
  RESULTS
  Normal parathyroid glands, parathyroid adenomas, and parathyroid hyperplasias showed a typical membranous E-cadherin staining pattern. Expression of Snail was found in 22/25 parathyroid adenomas and in all parathyroid hyperplasias. Twist was expressed in 22/25 of parathyroid adenomas and in 20/25 parathyroid hyperplasias. Snail and Twist positive cells were homogeneously distributed throughout the gland. However, in all nine parathyroid carcinomas, membranous E-cadherin staining was lost. In addition, the expression pattern of Snail and Twist was changed and mostly limited to the invasive front of cancer tissue samples.
  
  
  CONCLUSIONS
  Expression of Snail and Twist at the invasive front and consecutive loss of E-cadherin in parathyroid carcinomas suggests a key role of EMT in the tumorigenesis of this cancer. The unique expression pattern could help to distinguish between an adenoma and a non-metastatic carcinoma. Loss of E-cadherin and change of the expression pattern of Snail and Twist together should result in an en bloc resection or a close follow-up.
authors.affiliation: Department of Surgery, Philipps-University Marburg, Marburg, Germany. fendrich@med.uni-marburg.de
authors.forename: Volker
authors.initials: V
authors.lastname: Fendrich
authors.forename: Jens
authors.initials: J
authors.lastname: Waldmann
authors.forename: Georg
authors.initials: G
authors.lastname: Feldmann
authors.forename: Katja
authors.initials: K
authors.lastname: Schlosser
authors.forename: Alexander
authors.initials: A
authors.lastname: König
authors.forename: Annette
authors.initials: A
authors.lastname: Ramaswamy
authors.forename: Detlef K
authors.initials: DK
authors.lastname: Bartsch
authors.forename: Elias
authors.initials: E
authors.lastname: Karakas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D002471:Cell Transformation, Neoplastic / Q000378:metabolism*; D004847:Epithelial Cells / Q000502:physiology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000378:metabolism; D010281:Parathyroid Hormone / Q000097:blood; D010282:Parathyroid Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D000071250:Snail Family Transcription Factors; D016707:Tissue Fixation; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D051879:Twist-Related Protein 1 / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D015820:Cadherins; D010281:Parathyroid Hormone; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; D051879:Twist-Related Protein 1; D002118:Calcium