title: Frequency of Ki-67 (MIB-1) and P53 expressions among patients with prostate cancer.
abstract: BACKGROUND
  Prostate cancer is the most common malignant tumor in men. Tumor grade is one of the most important prognostic factors of prostate cancer. P53 and Ki-67 expressions have also been considered to be prognostic factors.
  
  
  OBJECTIVE
  This study was performed to investigate the frequency of these proteins expression and compare the obtained results with Gleason's grading.
  
  
  METHODS
  In this cross-sectional study, 49 paraffin blocks of prostate cancers were assessed. Tumor grade was determined according to the Gleason's criteria.
  
  
  METHODS
  Ki-67 and P53 expressions were determined by immunohistochemical staining.
  
  
  METHODS
  The obtained results were analyzed and evaluated using Spearman's statistical test (SPSS version 15).
  
  
  RESULTS
  Three out of 49 (6.1%) cases were well differentiated, 21 (43%) moderately differentiated and 25 (51%) were poorly differentiated. P53 was negative in all well-differentiated cases. Ki-67 was negative in 14 cases (28%) including all well-differentiated tumors. Among moderately and poorly differentiated tumors Ki-67 was negative in eight (38%) and three (12%) of cases, respectively. A statistically significant relation was observed between the increased Ki-67 labeling index (LI) and increased Gleason's grade. Conversely, no statistically significant relation was found between P53 expression and increased Gleason's grade.
  
  
  CONCLUSIONS
  According to the findings of this study, it seems that Ki-67 can be used as a prognostic factor for prostate cancer. On the other hand, the probable relation between P-53 and prostate cancer prognosis requires further studies.
authors.affiliation: Molecular Pathology Research Center, Emam Reza Hospital, Kermanshah University of Medical sciences, Kermanshah, Iran.
authors.forename: Seyed Hamid
authors.initials: SH
authors.lastname: Madani
authors.forename: Somayeh
authors.initials: S
authors.lastname: Ameli
authors.forename: Sedigheh
authors.initials: S
authors.lastname: Khazaei
authors.forename: Malek
authors.initials: M
authors.lastname: Kanani
authors.forename: Babak
authors.initials: B
authors.lastname: Izadi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D003430:Cross-Sectional Studies; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D019394:Ki-67 Antigen / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D012720:Severity of Illness Index; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53