Clinical and prognostic significance of HIF-1\u03b1 overexpression in oral squamous cell carcinoma: a meta-analysis

Abstract

BackgroundRecent studies have indicated an association between hypoxia inducible factor-1 alpha (HIF-1α) expression and poor prognosis in patients with oral squamous cell carcinoma (OSCC); however, definitive evidence of this association is yet to be obtained. We performed a meta-analysis to evaluate the association of HIF-1α expression with clinicopathological characteristics and overall survival (OS) of patients with OSCC.MethodsA literature search for relevant studies published in English language as of February 05, 2016, was performed on PubMed, Web of Science, and EMBASE databases. Eighteen studies with a combined study population of 1474 patients with OSCC are included in the meta-analysis. Odds ratio (OR) or hazard ratio (HR) with 95% confidence interval (CI) was calculated using random-effects model or fixed-effects model.ResultsHIF-1α overexpression was significantly associated with larger tumor size (OR = 2.28, 95% CI = 1.49–3.50, P = 0.017), advanced TNM stage (OR = 2.29, 95% CI = 1.50–3.49, P = 0.158), and lymph node metastasis (OR = 2.05, 95% CI = 1.19–3.53, P < 0.001), but not with poor differentiation (OR = 1.21, 95% CI = 0.55–2.64, P = 0.024). These results demonstrated an association between HIF-1α expression and biological behavior of OSCC. On pooled analyses, high expression of HIF-1α was associated with worse OS (HR = 1.70, 95% CI = 1.10–2.61, P < 0.001). On subgroup analyses, overexpression of HIF-1α was significantly associated with poor prognosis in Asian population (HR = 2.33, 95% CI = 1.72–3.15, P = 0.862).ConclusionsOur findings demonstrate an association of HIF-1α overexpression with tumor size, tumor stage, lymph node metastasis, and overall survival. HIF-1α could be an independent prognostic marker in patients with OSCC.