Abstract
BACKGROUND: The association of CD133 overexpression with clinicopathological significance and prognosis in patients with breast cancer remains controversial. We thus performed a meta-analysis to evaluate the role of CD133 expression in the development and prognosis of breast cancer. METHODS: The databases PubMed, Embase, and Cochrane Library (updated to August 1, 2016) were searched. Pooled odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (95% CI) were used to evaluate the impact of CD133 expression on clinicopathological features, overall survival, and disease-free survival. RESULTS: A total of 1,734 patients from 13 studies were subject to final analysis. The results showed a significant association between overexpression of CD133 and estrogen receptor status (OR 0.35, 95% CI 0.18-0.70), progesterone receptor status (OR 0.56, 95% CI 0.43-0.74), human epidermal growth factor-2 status (OR 1.81, 95% CI 1.33-2.45), lymph node metastasis (OR 1.98, 95% CI 1.34-2.92), and tumor histological grade (OR 1.79, 95% CI 1.26-2.54) in breast cancer. However, no significant correlation was found between upregulation of CD133 expression and onset age (OR 1.03, 95% CI 0.70-1.53) or tumor size (OR 1.29, 95% CI 0.80-2.09). Moreover, CD133-positive breast cancer patients had a higher risk of mortality (HR 1.91, 95% CI 1.21-3.03) and disease progression (HR 2.70, 95% CI 1.05-6.95). CONCLUSION: This meta-analysis suggested that CD133 might be a predictor of clinical outcomes as well as prognosis and could be a potentially new gene therapy target for breast cancer patients.