title: Increased macroH2A1.1 expression correlates with poor survival of triple-negative breast cancer patients.
abstract: OBJECTIVE
  Epithelial-Mesenchymal Transition (EMT) features appear to be key events in development and progression of breast cancer. Epigenetic modifications contribute to the establishment and maintenance of cancer subclasses, as well as to the EMT process. Whether histone variants contribute to these transformations is not known. We investigated the relative expression levels of histone macroH2A1 splice variants and correlated it with breast cancer status/prognosis/types.
  
  
  METHODS
  To detect differential expression of macroH2A1 variant mRNAs in breast cancer cells and tumor samples, we used the following databases: GEO, EMBL-EBI and publisher databases (may-august 2012). We extracted macroH2A1.1/macroH2A1 mRNA ratios and performed correlation studies on intrinsic molecular subclasses of breast cancer and on molecular characteristics of EMT. Associations between molecular and survival data were determined.
  
  
  RESULTS
  We found increased macroH2A1.1/macroH2A1 mRNA ratios to be associated with the claudin-low intrinsic subtype in breast cancer cell lines. At the molecular level this association translates into a positive correlation between macroH2A1 ratios and molecular characteristics of the EMT process. Moreover, untreated Triple Negative Breast Cancers presenting a high macroH2A1.1 mRNA ratio exhibit a poor outcome.
  
  
  CONCLUSIONS
  These results provide first evidence that macroH2A1.1 could be exploited as an actor in the maintenance of a transient cellular state in EMT progress towards metastatic development of breast tumors.
authors.affiliation: Université de Toulouse; Laboratoire de Biologie Moléculaire Eucaryote (LBME); F-31062 Toulouse, France; CNRS; LBME; F-31062 Toulouse, France.
authors.forename: Anne-Claire
authors.initials: AC
authors.lastname: Lavigne
authors.affiliation: Université de Toulouse; Laboratoire de Biologie Moléculaire Eucaryote (LBME); F-31062 Toulouse, France; CNRS; LBME; F-31062 Toulouse, France.
authors.forename: Magali
authors.initials: M
authors.lastname: Castells
authors.affiliation: Université de Toulouse; Laboratoire de Biologie Moléculaire Eucaryote (LBME); F-31062 Toulouse, France; CNRS; LBME; F-31062 Toulouse, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Mermet
authors.affiliation: Université de Toulouse; Laboratoire de Biologie Moléculaire Eucaryote (LBME); F-31062 Toulouse, France; CNRS; LBME; F-31062 Toulouse, France.
authors.forename: Silvia
authors.initials: S
authors.lastname: Kocanova
authors.affiliation: Université de Toulouse; Laboratoire de Biologie Moléculaire Eucaryote (LBME); F-31062 Toulouse, France; CNRS; LBME; F-31062 Toulouse, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Dalvai
authors.affiliation: Université de Toulouse; Laboratoire de Biologie Moléculaire Eucaryote (LBME); F-31062 Toulouse, France; CNRS; LBME; F-31062 Toulouse, France.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Bystricky
mesh_terms: D017398:Alternative Splicing; D045744:Cell Line, Tumor; D044127:Epigenesis, Genetic; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D006657:Histones / Q000235:genetics*; D006801:Humans; D011379:Prognosis; D016019:Survival Analysis; D064726:Triple Negative Breast Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology
chemical_list: D006657:Histones; C120756:macroH2A histone