title: Comparison of positivity frequency of bcl-2 expression in prostate adenocarcinoma with low and high Gleason score.
abstract: BACKGROUND
  Multiple genetic and epigenetic factors have been implicated in the oncogenesis and progression of prostate cancer. The major difficulty is in that the clinical management stems from the reality that reliable and accurate prognostic biomarkers are not available and that effective treatment regimens forming hormone-resistant prostate cancers are yet to be developed. Among the most important regulators of apoptosis and programmed cell death is the bcl-2 gene and its related proteins. Elevated levels of bcl-2 protein may contribute to the progression of prostate cancers to a metastatic and hormone-insensitive state characterized by poor responses to chemotherapy.
  
  
  OBJECTIVE
  To characterize the expression of bcl-2 proteins as a prognostic factor in humans.
  
  
  METHODS
  A retrospective approach.
  
  
  METHODS
  Urology section, Federal University of São Paulo. DIAGNOSTIC TEST USED: Immunohistochemical analysis using bcl-2 protein antibody and normal staining by hematoxylin-eosin.
  
  
  METHODS
  Prognostic relations and protein expression were evaluated considering the total sample (28) divided into two groups, high (8 to 10) and low (2 to 4), separated according to the histological differentiation grade (Gleason score) with 10 and 18 samples, respectively.
  
  
  RESULTS
  The differentiation of grade into two groups separated according to the Gleason score in low and high types presented different bcl-2 expression (P < 0.001).
  
  
  CONCLUSIONS
  The higher frequency of bcl-2 immunostaining in tumor samples was observed in association with more advanced Gleason scores and suggests that an increase in the ratio of this anti-apoptotic protein often occurs during progression of prostate cancers.
authors.affiliation: Department of Surgery, Discipline of Urology, Universidade Federal de São Paulo/Escola Paulista de Medicina, São Paulo, Brazil.
authors.forename: F L
authors.initials: FL
authors.lastname: Hering
authors.forename: M V
authors.initials: MV
authors.lastname: Lipay
authors.forename: M A
authors.initials: MA
authors.lastname: Lipay
authors.forename: P R
authors.initials: PR
authors.lastname: Rodrigues
authors.forename: L J
authors.initials: LJ
authors.lastname: Nesralah
authors.forename: M
authors.initials: M
authors.lastname: Srougi
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry* / Q000473:pathology; D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000032:analysis; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000737:chemistry* / Q000473:pathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor; D019253:Proto-Oncogene Proteins c-bcl-2