title: Expression of the tumor markers sialyl Lewis A, sialyl Lewis X, Lewis Y, Thomsen-Friedenreich antigen, galectin-1 and galectin-3 in human osteoblasts in vitro.
abstract: OBJECTIVE
  Lewis antigens and the Thomsen-Friedenreich (TF) antigen are complex glycan structures that modulate processes such as cell adhesion and proliferation and tumor metastasis. The aim of our study was to analyze the expression of sialyl Lewis A (sLeA), sialyl Lewis X (sLeX), Lewis Y (LeY), TF, galectin-1 (Gal-1) and galectin-3 (Gal-3) in human osteoblasts in vitro.
  
  
  METHODS
  The expression of the tumor markers sLeA, sLeX, LeY, TF, Gal-1 and Gal-3 was studied by means of immunohistochemistry on cells grown on chamber slides (2D) and on paraffin sections three-dimensional scaffold-free cultures (3D). The results of the stainings were evaluated semiquantitatively with the immunoreactive scoring system (IRS).
  
  
  RESULTS
  Analysis of sLeA expression in both types of culture, 2D and 3D showed no detectable staining. After 5 days, in the 2D culture, expression of sLeX was weak, but the 3D culture (after 56 weeks) displayed a strong expression. LeY was expressed very slightly in the 2D culture, however LeY was not detectable in the 3D culture. The TF epitope was identified in the 2D cell culture model. In the 3D model, however, TF was completely lacking. Gal-1 was expressed very strongly in 2D culture, but in the 3D culture was not detectable. In contrast, Gal-3 was expressed in 3D culture but not in 2D.
  
  
  CONCLUSIONS
  Within this study, we present a systematic analysis of the expression of sLeA, sLeX, LeY, TF, Gal-1 and Gal-3 in human osteoblasts grown in 2D and in 3D scaffold-free cultures. Summarizing the results of our study, we suggest that Lewis antigens and Gal-1 and -3 might play an important role in cell-cell and cell-matrix interactions of osteoblastic cells.
authors.affiliation: Clinic of Orthopedics and Sportorthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Strasse 22, 81675 Munich, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Tübel
authors.forename: B
authors.initials: B
authors.lastname: Saldamli
authors.forename: I
authors.initials: I
authors.lastname: Wiest
authors.forename: U
authors.initials: U
authors.lastname: Jeschke
authors.forename: R
authors.initials: R
authors.lastname: Burgkart
mesh_terms: D015295:Antigens, Tumor-Associated, Carbohydrate / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D018395:CA-19-9 Antigen; D002478:Cells, Cultured; D037483:Galectin 1 / Q000032:analysis; D037502:Galectin 3 / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007983:Lewis Blood Group Antigens / Q000032:analysis; D016256:Lewis X Antigen / Q000032:analysis; D009844:Oligosaccharides / Q000032:analysis; D010006:Osteoblasts / Q000737:chemistry*; D000080506:Sialyl Lewis X Antigen
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D037483:Galectin 1; D037502:Galectin 3; C445499:LGALS1 protein, human; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen; C094162:Lewis Y antigen; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; C016467:Thomsen-Friedenreich antigen