title: Distinct expression of cytokeratin, N-cadherin and CD133 in circulating tumor cells of metastatic breast cancer patients.
abstract: OBJECTIVE
  Circulating tumor cells (CTCs) appear as potential candidates to predict the ability of breast tumors to metastasize. Moreover, epithelial-mesenchymal transition (EMT) and stem cell features are major mechanisms for metastasis.
  
  
  METHODS
  Using a triple fluorescence technique, the expression of EMT (N-cadherin) and stem cell markers (CD133) was analyzed in CTCs detected via cytokeratin in blood samples from 26 metastatic breast cancer patients.
  
  
  RESULTS
  We detected CTCs in 100% of the patients (n = 831 CTCs). In total, 67% of the CTCs were N-cadherin and CD133 negative. Nonetheless, 87.8 and 57.6%, respectively, of the CTCs that expressed one marker coexpressed the other. Both double-negative and double-positive CTCs were present in more than 90% of the patients. Within the CTCs of each patient, we demonstrated striking heterogeneities of marker expressions, cell shapes, clusters and sizes.
  
  
  CONCLUSIONS
  These data outline the importance of characterizing CTCs, especially through stem cell and EMT markers.
authors.affiliation: Klinik und Poliklinik für Frauenheilkunde und Geburtshilfe, Campus Innenstadt, Klinikum der Ludwig-Maximilians-Universität, Maistraße 11, 80337 Munich, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Bock
authors.forename: Brigitte
authors.initials: B
authors.lastname: Rack
authors.forename: Jens
authors.initials: J
authors.lastname: Huober
authors.forename: Ulrich
authors.initials: U
authors.lastname: Andergassen
authors.forename: Udo
authors.initials: U
authors.lastname: Jeschke
authors.forename: Sophie
authors.initials: S
authors.lastname: Doisneau-Sixou
mesh_terms: D000071916:AC133 Antigen; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D015331:Cohort Studies; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D015870:Gene Expression; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007633:Keratins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000378:metabolism*; D014411:Neoplastic Stem Cells; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D015203:Reproducibility of Results
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D014408:Biomarkers, Tumor; D015820:Cadherins; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D007633:Keratins
keywords: CD133; EMT; N-cadherin; breast cancer; circulating tumor cells; stem cells