title: The metabolic marker tumour pyruvate kinase type M2 (tumour M2-PK) shows increased expression along the metaplasia-dysplasia-adenocarcinoma sequence in Barrett's oesophagus.
abstract: BACKGROUND
  Proliferating and tumour cells express the glycolytic isoenzyme, pyruvate kinase type M2 (M2-PK). In tumours cells, M2-PK usually exists in dimeric form (tumour M2-PK), causing the accumulation of glycolytic phosphometabolites, which allows cells to invade areas with low oxygen and glucose concentrations.
  
  
  OBJECTIVE
  To investigate the expression of tumour M2-PK during the metaplasia-dysplasia-adenocarcinoma sequence of Barrett's oesophagus, and to assess the prognostic usefulness of tumour M2-PK in oesophageal cancer.
  
  
  METHODS
  One hundred and ninety cases selected from the histopathology archives as follows: 17 reflux oesophagitis, 37 Barrett's oesophagus, 21 high grade dysplasia, 112 adenocarcinomas, and three control tumours. Sections were stained immunohistochemically with antibody to tumour M2-PK.
  
  
  RESULTS
  Tumour M2-PK was expressed in all cases, and increased cytoplasmic expression was seen with progression along the metaplasia-dysplasia-adenocarcinoma sequence. All cases of adenocarcinoma showed 100% staining so that tumour M2-PK was not a useful prognostic marker.
  
  
  CONCLUSIONS
  Tumour M2-PK is not a specific marker of Barrett's adenocarcinoma, but may be important as a marker of transformed and highly proliferating clones during progression along the metaplasia-dysplasia-adenocarcinoma sequence.
authors.affiliation: Department of Gastroenterology, University Hospital Birmingham, Edgbaston, Birmingham B15 2TH, UK. konradkoss@yahoo.com
authors.forename: K
authors.initials: K
authors.lastname: Koss
authors.forename: R F
authors.initials: RF
authors.lastname: Harrison
authors.forename: J
authors.initials: J
authors.lastname: Gregory
authors.forename: S J
authors.initials: SJ
authors.lastname: Darnton
authors.forename: M R
authors.initials: MR
authors.lastname: Anderson
authors.forename: J A Z
authors.initials: JA
authors.lastname: Jankowski
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology* / Q000473:pathology; D001471:Barrett Esophagus / Q000201:enzymology* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D003593:Cytoplasm / Q000378:metabolism; D004938:Esophageal Neoplasms / Q000208:ethnology* / Q000473:pathology; D004942:Esophagitis, Peptic / Q000201:enzymology / Q000473:pathology; D004947:Esophagus / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007413:Intestinal Mucosa / Q000473:pathology; D008679:Metaplasia / Q000201:enzymology / Q000473:pathology; D011379:Prognosis; D011770:Pyruvate Kinase / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D011770:Pyruvate Kinase