title: Low protein expression of MET in ER-positive and HER2-positive breast cancer.
abstract: OBJECTIVE
  The mesenchymal-epithelial transition factor (MET) is a receptor tyrosine kinase that plays a key role in cell survival, growth, angiogenesis and metastasis. Because its expression is frequently altered in tumors, MET is currently under investigation as a potential target for anticancer therapy. The purpose of the present study was to determine the prognostic value of tumor MET expression levels in patients with estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-positive breast cancer, in order to strengthen the rationale for targeted therapy using MET inhibitors in this breast cancer subpopulation.
  
  
  METHODS
  We determined the expression of MET in formalin-fixed paraffin-embedded surgical specimens of ER- and HER2-positive breast cancer by immunohistochemistry.
  
  
  RESULTS
  Comparisons of MET expression with clinical parameters, including survival of the patients, were performed with MET expression as a dichotomized variable classified as high or low. Out of 78 tumors, 3 (3.8%) showed high MET expression. The analysis examining the association between MET and survival did not yield any statistically significant result regarding overall survival or disease-free survival.
  
  
  CONCLUSIONS
  ER- and HER2-positive breast carcinomas do not exhibit high MET expression. This null finding, the first to be reported in the literature, is of great importance, since it indicates that this sub-group population is not proper candidate for clinical trials with MET inhibitors.
authors.affiliation: Associate Professor; Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna, Austria. martin.filipits@meduniwien.ac.at.
authors.forename: Flora
authors.initials: F
authors.lastname: Zagouri
authors.forename: Anita
authors.initials: A
authors.lastname: Brandstetter
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Moussiolis
authors.forename: Dimosthenis
authors.initials: D
authors.lastname: Chrysikos
authors.forename: Constantine
authors.initials: C
authors.lastname: Dimitrakakis
authors.forename: Alexandra
authors.initials: A
authors.lastname: Tsigginou
authors.forename: Spyros
authors.initials: S
authors.lastname: Marinopoulos
authors.forename: George C
authors.initials: GC
authors.lastname: Zografos
authors.forename: Theodoros N
authors.initials: TN
authors.lastname: Sergentanis
authors.forename: Meletios-Athanassios
authors.initials: MA
authors.lastname: Dimopoulos
authors.forename: Martin
authors.initials: M
authors.lastname: Filipits
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000473:pathology; D018275:Carcinoma, Lobular / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D019859:Proto-Oncogene Proteins c-met / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D019859:Proto-Oncogene Proteins c-met; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human; C491743:MET protein, human
keywords: Biomarkers; ER-positive; HER2-positive; MET; breast cancer; prognosis