Prognostic role of high Bmi-1 expression in Asian and Caucasian patients with solid tumors: a meta-analysis

Biomed Pharmacother. 2014 Oct;68(8):969-77. doi: 10.1016/j.biopha.2014.10.017. Epub 2014 Oct 29.

Abstract

Recently, many studies have shown that the B-cell-specific moloney leukemia virus insertion site 1 (Bmi-1) exhibits altered expression in various cancers and may serve as prognostic biomarkers. We performed a meta-analysis to evaluate the prognostic role of Bmi-1 expression in solid cancers. Studies were recruited by searching PubMed, Embase and the Cochrane Library. Thirty-nine articles including 40 studies were involved in this meta-analysis. Our results indicated that the Bmi-1 showed the opposite prognostic effect in Asian and Caucasian populations. High Bmi-1 expression as a negative predictor for overall survival (OS) in Asian patients (HR=1.96, 95% CI 1.62-2.36), but a positive predictor in Caucasian populations (HR=0.77, 95% CI 0.63-0.93). Furthermore, we took a further subgroup analysis based on tumor type in these two populations, respectively. In Asian cases, high expression of Bmi-1 was associated with poor OS in oesophageal carcinoma (HR=1.93, 95% CI 1.52-2.46), gastric cancer (HR=1.50, 95% CI 1.22-1.85), lung cancer (HR=1.73, 95% CI 1.05-2.85), cervical cancer (HR=2.80, 95% CI 2.26-3.47) and colorectal cancer (HR=3.36, 95% CI 2.19-5.15), rather than in breast cancer and HCC. In Caucasian populations, high expression of Bmi-1 was associated with better OS in breast cancer (HR=0.70, 95% CI 0.51-0.97), but it showed no significance in oesophageal carcinoma. In conclusion, high Bmi-1 expression was significantly associated with poor survival in Asian patients with oesophageal carcinoma, gastric cancer, lung cancer, colorectal cancer and cervical carcinoma, whereas high level of Bmi-1 can predict better prognosis in Caucasian patients with breast cancer.

Keywords: Bmi-1; Cancer; Meta-analysis; Prognosis.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Asian People* / genetics
  • Biomarkers, Tumor / biosynthesis*
  • Biomarkers, Tumor / genetics
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Neoplasms / genetics
  • Neoplasms / metabolism*
  • Polycomb Repressive Complex 1 / biosynthesis*
  • Polycomb Repressive Complex 1 / genetics
  • Prognosis
  • White People* / genetics

Substances

  • BMI1 protein, human
  • Biomarkers, Tumor
  • Polycomb Repressive Complex 1