The Role of HIF-1α Expression in Prostate Cancer: A Meta-Analysis

Objective To provide a comprehensive meta-analysis of the extent of the possible association between hypoxia-inducible factor 1α （HIF-1α） and the risk of prostate cancer （PCa）. Methods Such databases including PubMed, The Cochrane Library, EMBASE, CNKI, and VIP Database were searched from inception to May 1st 2016, for studies about the association of the clinical significance and prognostic value of HIF-1α expression in PCa. Then, meta-analysis was performed using RevMan 5.3 software. The NOS scale was used to evaluate the quality of the literature. Results Nineteen relevant studies, which had a total of 1 503 patients enrolled, involving 1 125 PCa, 378 benign prostatic hyperplasia （BPH）. The results of meta-analysis showed that: HIF-1α protein expression was higher in PCa group than that in BPH group （OR=14.30, 95%CI 7.41~27.60）. The results of the meta-analysis showed significant associations between HIF-1α protein expression and higher tumor stage （C+D and Ⅲ+Ⅳ）, high tumor grade or positive lymph node metastatic status, respectively, the combined ORs and 95%CI were as follows: OR=8.51, 95%CI 4.90~14.80; OR=4.93, 95%CI 2.84~8.57; OR=5.53, 95%CI 3.74~8.18; OR=7.09, 95%CI 3.87~12.98. There was no significant association between HIF-1α protein expression and age （>65 vs. ≤65）, the combined OR and 95%CI were OR 1.66, 95%CI 0.86~3.20. Additionally, significant correlations between HIF-1α protein expression and survival outcome （progression-free survival and metastasis-free survival） were also observed in PCa patients, the combined OR and 95%CI were OR 0.37, 95%CI 0.17~0.81; OR 9.80, 95%CI 1.50~63.86. Conclusion The present results indicate that over-expression of HIF-1α is distinctly correlated with an increased risk and poorer survival in PCa patients. HIF-1α may serve as a valuable biomarker for prognosis in PCa patients.