The association of HIF-1α expression with clinicopathological significance in prostate cancer: a meta-analysis

Background: Hypoxia-inducible factor-1α (HIF-1α) plays an important role in tumor growth, invasion, and metastasis. The aim of this study was to perform a meta-analysis to explore the association of HIF-1α expression with clinicopathological significance in patients with prostate cancer (PCa). Methods: A detailed literature search was made in PubMed, Embase, Cochrane Library, China Biology Medicine disc (CBM), and China National Knowledge Infrastructure (CNKI) up to August 21, 2017. Odds ratios (ORs) with 95% CIs were calculated to evaluate the strength of the correlations. Analysis of pooled data was performed using Review Manager 5.3 software. Results: Eventually, 14 studies were identified and involved in this meta-analysis. The rate of HIF-1α protein expression was significantly higher in PCa than in nonmalignant prostate tissues (OR=12.01, 95% CI: 8.22-17.55, P<0.00001). Similar results were found in different subgroups. There were significant differences between HIF-1α expression and clinicopathological significance. The expression of HIF-1α protein was significantly associated with Gleason score (Gleason ≥7 vs Gleason <7: OR=3.58, 95% CI: 2.35-5.46, P<0.00001). The frequency of HIF-1α protein expression was significantly higher in T3-T4 stages than in T1-T2 stages of PCa (OR=3.70, 95% CI: 1.53-8.96, P=0.004). The expression of HIF-1α protein was significantly associated with the presence of lymph node and/or bone metastasis of PCa (metastasis positive vs negative: OR=7.07, 95% CI: 4.08-12.25, P<0.00001). Conclusion: Taken together, our findings have demonstrated the certain associations of HIF-1α expression with an increased risk and clinicopathological significance in PCa patients, indicating that HIF-1α may serve as a valuable biomarker for diagnosing PCa and monitoring the progression.