title: Nuclear expression of snail is an independent negative prognostic factor in human breast cancer.
abstract: BACKGROUND
  Snail is a key regulator of epithelial-mesenchymal transition of tumor cells. Several studies have shown nuclear Snail expression to be a negative prognostic factor in human cancer, where it is generally associated with more aggressive tumor behavior and worse survival.
  
  
  OBJECTIVE
  To further explore the role of Snail expression in breast cancer, we conducted a study on a tissue microarray, encompassing 1043 breast cancer cases.
  
  
  RESULTS
  A total of 265 (25.4%) breast cancers were positive for Snail. Snail expression was significantly associated with greater tumor size, higher tumor stage and grade, positive lymph node status, and hormone receptor negative status and was differently expressed in the intrinsic subtypes of breast cancer, being the highest in the basal-like subtype and the lowest in the luminal A subtype. In multivariate analysis, Snail proved to be an independent negative prognostic factor for OS. In the intrinsic subtypes, Snail expression was a negative prognostic factor for OS in the luminal B HER2(-), the luminal B HER2(+), and the basal-like subtype.
  
  
  CONCLUSIONS
  This is the first study demonstrating that nuclear Snail expression is an independent negative predictor of prognosis in breast cancer, thus suggesting that it may represent a potential therapeutic target.
authors.affiliation: Institute of Pathology, University Hospital Basel, Schoenbeinstraße 40, 4031 Basel, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Muenst
authors.forename: S
authors.initials: S
authors.lastname: Däster
authors.forename: E C
authors.initials: EC
authors.lastname: Obermann
authors.forename: R A
authors.initials: RA
authors.lastname: Droeser
authors.forename: W P
authors.initials: WP
authors.lastname: Weber
authors.forename: U
authors.initials: U
authors.lastname: von Holzen
authors.forename: F
authors.initials: F
authors.lastname: Gao
authors.forename: C
authors.initials: C
authors.lastname: Viehl
authors.forename: D
authors.initials: D
authors.lastname: Oertli
authors.forename: S D
authors.initials: SD
authors.lastname: Soysal
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D002467:Cell Nucleus / Q000378:metabolism*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors