title: Enhancer of zeste homologue 2 expression in breast carcinoma smears in relationship with p53, Ki-67 and other prognostic parameters.
abstract: BACKGROUND
  The polycomb group protein enhancer of zeste homologue 2 (EZH 2) has been reported as a marker of aggressive breast cancer. The aim of this study was to investigate the correlation between the expression of EZH 2 with p53 and Ki-67 expression and other clinicopathological parameters in primary breast carcinomas in order to determine the role of the above marker as a prognosticator of tumor aggressiveness and patient outcome.
  
  
  METHODS
  One hundred primary operable breast cancer patients were investigated in order to identify the expression of EZH 2, Ki-67 and p53 in imprint smears immunocytochemically. The prevalence of expression of these markers was then correlated with clinicopathological parameters. Follow-up was available for all patients.
  
  
  RESULTS
  EZH 2 was expressed in 64% of the cases and correlated with higher levels of p53 (relative risk = 3.00, p < 0.0001) and Ki-67 (relative risk = 3.25, p < 0.0001). Malignant cells showed immunoreactivity for all markers in the nucleus. Univariate analysis revealed a strong association between EZH 2 protein expression and tumor grade and size, lymph node metastasis, and HER-2 and estrogen and progesterone receptor status. Multivariable statistical analysis revealed that lymph node metastasis was the main predictor for EZH 2 expression. Decreased patient survival was also significantly associated with EZH 2 expression (p < 0.0001).
  
  
  CONCLUSIONS
  EZH 2 expression may be a marker of poor prognosis in breast carcinoma patients and has been suggested as a candidate for targeted therapy.
authors.affiliation: Division of Cytology, First Department of Pathology, University of Athens Medical School, Athens, Greece.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Athanassiadou
authors.forename: Angelos
authors.initials: A
authors.lastname: Tsipis
authors.forename: Efstratios
authors.initials: E
authors.lastname: Patsouris
authors.forename: Maria
authors.initials: M
authors.lastname: Gonidi
authors.forename: Polyxeni
authors.initials: P
authors.lastname: Nicolopoulou-Stamati
authors.forename: George
authors.initials: G
authors.lastname: Chelidonis
authors.forename: Pauline
authors.initials: P
authors.lastname: Athanassiadou
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000473:pathology; D002467:Cell Nucleus / Q000473:pathology; D016009:Chi-Square Distribution; D003584:Cytological Techniques; D004268:DNA-Binding Proteins / Q000378:metabolism*; D000071221:Enhancer of Zeste Homolog 2 Protein; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D016015:Logistic Models; D008875:Middle Aged; D063151:Polycomb Repressive Complex 2; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D016019:Survival Analysis; D014157:Transcription Factors / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D019394:Ki-67 Antigen; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; C498409:EZH2 protein, human; D000071221:Enhancer of Zeste Homolog 2 Protein; D063151:Polycomb Repressive Complex 2