title: Tumor type M2 pyruvate kinase expression in advanced breast cancer.
abstract: BACKGROUND
  Recently, a high validity correlation of the tumor M2 pyruvate kinase (Tu M2-PK) isoenzyme in comparison to standard tumor markers has been demonstrated in solid tumors. We investigated this marker in 67 patients with advanced breast cancer (ABC) in comparison to healthy controls.
  
  
  METHODS
  Plasma Tu M2-PK was measured using an ELISA assay (ScheBo Tech, Giessen, Germany) while serum CA27.29 was determined using a chemiluminescent immunoassay (Bayer Diagnostics, Tarrytown, USA).
  
  
  RESULTS
  In a ROC analysis, the cut-off to discriminate patients from controls was established at 15 U/ml for Tu M2-PK (specificity 85%; positive predictive value 81%) and 30 U/ml for CA27.29 (specificity 91%; positive predictive value 92%). Median ABC baseline levels (ranges) in patients with ABC for Tu M2-PK and CA27.29 were 12.8 U/ml (4.8-252,495) and 130 U/ml (13.3-8130), respectively. Response assessment was done in 45 chemotherapy courses of 38 pts. In 13 out of 19 blocks (68.4%) with PD (progressive disease), an elevated level of Tu M2-PK at baseline or in the follow-up was found. In 17 out of 20 blocks (85%) with SD (stable disease), the Tu M2-PK level was normal at baseline or normalised within 4 weeks of treatment. All 6 patients with disease remission had a normal baseline Tu M2-PK level or the levels decreased promptly.
  
  
  CONCLUSIONS
  Tu M2-PK gives additional information about ABC, indicating disease activity and sensitivity to chemotherapy while CA27.29 reflects tumor burden.
authors.affiliation: Schwerpunkt Onkologie und Hämatologie, Universitätsklinikum Charité, Campus Mitte, Humboldt-Universität Berlin, Schumannstr. 20-21, 10117 Berlin, Germany. Diana.Lueftner@rz.hu-berlin.de
authors.forename: D
authors.initials: D
authors.lastname: Lüftner
authors.forename: J
authors.initials: J
authors.lastname: Mesterharm
authors.forename: C
authors.initials: C
authors.lastname: Akrivakis
authors.forename: R
authors.initials: R
authors.lastname: Geppert
authors.forename: P E
authors.initials: PE
authors.lastname: Petrides
authors.forename: K D
authors.initials: KD
authors.lastname: Wernecke
authors.forename: K
authors.initials: K
authors.lastname: Possinger
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011379:Prognosis; D011770:Pyruvate Kinase / Q000096:biosynthesis*; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D011770:Pyruvate Kinase