Clinicopathological Differences and Prognostic Value of Hypoxia-Inducible Factor-2α Expression for Gastric Cancer:...

Published literatures have reported the relationship between hypoxic-inducible factor-2α (HIF-2α) expression and clinicopathological features in gastric cancer (GC), but the evaluated conclusions remain controversial. A meta-analysis was carried to examine the clinicopathological features and prognostic values of HIF-2α in patients with GC. Systematic detailed searches were performed to Pub Med, Cochrane Library, and EBSCO until to August 2015. Six studies (508 specimens) were included in this meta-analysis. HIF-2α-positive expression indicates an unfavorable prognosis value and advanced clinicopathological differences for the available patient dates with GC. Further multivariate meta-analysis revealed that HIF-2α-positive expression in gastric cancer associated with deeper tumor infiltration (OR = 3.08; 95%CI: 1.18-8.04), higher rates of lymphatic metastasis (OR = 3.26; 95%CI: 1.10-9.63), higher TNM stage (III+IV) (OR = 2.61; 95%CI: 1.40-4.84), and much lower 5-year overall survival (OR = 2.08; 95%CI: 1.21-3.58). Nevertheless, there is no association between HIF-2α-positive expression and worse tumor differentiation (OR = 2.03; 95%CI: 0.73-5.64). In addition, by this subgroup analysis, HIF-2α-positive expression associated with deeper tumor infiltration (OR = 3.81; 95%CI: 1.03-14.08), higher lymphatic metastasis (OR = 4.71; 95%CI: 1.08-20.50), higher TNM stage (OR = 3.21; 95%CI: 1.57-6.57), worse tumor differentiation (OR = 3.08; 95%CI: 1.51-6.31), and lower 5-year overall survival (OR = 2.34; 95%CI: 1.15-4.79). Our results indicate that HIF-2α overexpression can potently predict the poor prognosis and may be a potential therapeutic target for gastric carcinoma, according to the limited evidence. Meanwhile, further studies are needed to elucidate the accuracy of these results.