title: Detection of protein alterations in male breast cancer using two dimensional gel electrophoresis and mass spectrometry: the involvement of several pathways in tumorigenesis.
abstract: BACKGROUND
  Little emphasis has been placed today on the elucidation of protein alterations in male breast carcinogenesis.
  
  
  METHODS
  Protein extracts were subjected to both isoelectric focusing (IEF) and non-equilibrium pH gradient electrophoretic (NEPHGE) analyses. Differentially expressed proteins in tumor tissues were identified by matrix assisted laser desorption /ionization time of flight (MALDI-TOF) mass spectrometry and database search.
  
  
  RESULTS
  Some of the alterations involve variations in the expression of cytokeratins 8, 18 and 19. More interestingly, tropomyosin1, a protein known to play a role in suppression of the malignant phenotype, was found to be under-expressed in cancer tissues, implicating a possible pivotal role for this protein in male breast carcinogenesis. Co-upregulation of molecular chaperones (heat shock protein HSP27 and protein disulfide isomerase), stress related proteins (peroxiredoxin 1 and peptidylprolyl isomerase A) and glycolytic enzymes (enolase 1) occurred also in male breast tumors. Some of the remaining alterations include proteins involved in invasion and metastasis, such as galectin 1 and cathepsin D.
  
  
  CONCLUSIONS
  The present study represents a first proteomic investigation of protein alterations in infiltrating ductal carcinomas (IDCA) of the male breast. A number of protein alterations in tumor tissues have been characterised thus, providing new insights into the molecular mechanisms underlying this disease.
authors.affiliation: Laboratoire d'Immuno-Oncologie Moléculaire, Faculté de Médecine de Monastir, Monastir, Tunisia. k.chahed@yahoo.fr
authors.forename: Karim
authors.initials: K
authors.lastname: Chahed
authors.forename: Maria
authors.initials: M
authors.lastname: Kabbage
authors.forename: Bechr
authors.initials: B
authors.lastname: Hamrita
authors.forename: Christelle Lemaitre
authors.initials: CL
authors.lastname: Guillier
authors.forename: Mounir
authors.initials: M
authors.lastname: Trimeche
authors.forename: Sami
authors.initials: S
authors.lastname: Remadi
authors.forename: Laurence
authors.initials: L
authors.lastname: Ehret-Sabatier
authors.forename: Lotfi
authors.initials: L
authors.lastname: Chouchane
mesh_terms: D000595:Amino Acid Sequence; D018567:Breast Neoplasms, Male / Q000378:metabolism* / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000378:metabolism* / Q000473:pathology; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000737:chemistry / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009363:Neoplasm Proteins