title: Increased polycomb-group oncogene Bmi-1 expression correlates with poor prognosis in hepatocellular carcinoma.
abstract: OBJECTIVE
  Recent studies have identified polycomb-group gene Bmi-1 as oncogene in the generation of mouse pre-cell lymphomas, and overexpression of Bmi-1 has been found in several human tumor with the disease progress and poor prognosis of the cancer patients.
  
  
  METHODS
  In present study, we investigated Bmi-1 expression and its prognostic significance in hepatocellular carcinoma (HCC) by performing immunohistochemical analysis, using a total of 137 HCC clinical tissue samples.
  
  
  RESULTS
  High Bmi-1 expression (Bmi-1 2+ or 3+) was shown in 29.9% cases. The positive immuno-staining of Bmi-1 was not only in well/moderately-differentiated tumor cells, but also in surrounding noncancerous or cirrhotic liver tissue. Bmi-1 expression level did not correlate with any clinicopathological parameters. However, survival analysis showed that the high-Bmi-1 group had a significantly shorter overall survival time than the low-Bmi-1 group (P=0.047). Multivariate analysis after 24 months revealed that Bmi-1 expression was a significant and independent prognostic parameter (P=0.002) for HCC patients.
  
  
  CONCLUSIONS
  Our study indicated that Bmi-1 could be a candidate biomarker for long-term survival in HCC.
authors.affiliation: State Key Laboratory of Oncology in Southern China and Department of Experimental Research, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Yuexiu District, Guangzhou, Guangdong Province 510060, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Ke
authors.initials: K
authors.lastname: Pan
authors.forename: Hua-kun
authors.initials: HK
authors.lastname: Zhang
authors.forename: De-sheng
authors.initials: DS
authors.lastname: Weng
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Jian-jun
authors.initials: JJ
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Hai-feng
authors.initials: HF
authors.lastname: Song
authors.forename: Min-shan
authors.initials: MS
authors.lastname: Chen
authors.forename: Jian-chuan
authors.initials: JC
authors.lastname: Xia
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008113:Liver Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000096:biosynthesis*; D063150:Polycomb Repressive Complex 1; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D012097:Repressor Proteins / Q000096:biosynthesis*
chemical_list: C069077:BMI1 protein, human; D014408:Biomarkers, Tumor; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D063150:Polycomb Repressive Complex 1