title: Tissue microarray-based study of patients with lymph node-positive breast cancer shows tyrosine phosphorylation of signal transducer and activator of transcription 3 (tyrosine705-STAT3) is a marker of good prognosis.
abstract: BACKGROUND
  Although lymph node-positive breast cancers are associated with poorer prognosis, individual patients may have different clinical outcomes. Signal transducer and activator of transcription 3 (STAT3) is a point of convergence for numerous oncogenic signalling pathways. The goal of this study was to determine the prognostic value of phosphorylated (tyrosine705)-STAT3 in node-positive breast cancer patients.
  
  
  METHODS
  Immunohistochemical analysis of Phospho- STAT3 was performed on a tissue microarray of breast cancer specimens. The expression pattern of Phospho-STAT3 was correlated with survival outcome, and clinical and pathological parameters.
  
  
  RESULTS
  Out of 125 interpretable tumours, positive Phospho- STAT3 nuclear expression was seen in 35 (28%) of tumours. There was no significant relationship between Phospho-STAT3 expression and clinical-pathological parameters including age, hormonal receptor status, grade and tumour size. Interestingly positive tumours had a significantly improved disease-free survival at 5 years (p=0.035). Additionally, positive Phospho-STAT3 nuclear expression was correlated with significantly improved survival at both 5 years (p=0.023) and 10 years (p=0.026). Finally, in multivariate analyses Phospho-STAT3 was found to be an independent prognostic marker of overall survival in node-positive breast cancer patients.
  
  
  CONCLUSIONS
  These findings support the role of Phospho- STAT3 as an important independent prognostic marker in node-positive breast cancer patients.
authors.affiliation: Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Ein Kerem, POB 12000, Jerusalem 91120, Israel. amirsonn@gmail.com
authors.forename: Amir
authors.initials: A
authors.lastname: Sonnenblick
authors.forename: Anat
authors.initials: A
authors.lastname: Shriki
authors.forename: E
authors.initials: E
authors.lastname: Galun
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Axelrod
authors.forename: Hagit
authors.initials: H
authors.lastname: Daum
authors.forename: Yakir
authors.initials: Y
authors.lastname: Rottenberg
authors.forename: Tamar
authors.initials: T
authors.lastname: Hamburger
authors.forename: Bela
authors.initials: B
authors.lastname: Mali
authors.forename: Tamar
authors.initials: T
authors.lastname: Peretz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D002277:Carcinoma / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000378:metabolism* / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D010766:Phosphorylation; D011379:Prognosis; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000378:metabolism* / Q000502:physiology; D016019:Survival Analysis; D046888:Tissue Array Analysis / Q000379:methods; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases