Hypoxia-inducible factors in cancer: an overview of major findings from meta-analyses

This paper aims to systematically review the major findings from meta-analyses regarding the impact of hypoxia-inducible factors (HIFs) in various human cancers. A total of 56 eligible meta-analysis papers were identified via the PubMed and EMBASE databases. The associations of HIF-1α gene polymorphism and/or HIF-1α and HIF-2α protein expression with the risk, clinicopathological features, and/or survival were explored in head and neck cancer (n=4), glioma (n=2), oral cancer (n=10), oropharyngeal cancer (n=1), nasopharyngeal cancer (n=1), lung cancer (n=12), breast cancer (n=17), esophageal cancer (n=5), gastric cancer (n=8), colorectal cancer (n=15), pancreatic cancer (n=8), hepatocellular carcinoma (n=5), prostate cancer (n=13), renal cancer (n=13), bladder cancer (n=3), ovarian cancer (n=3), cervical cancer (n=10), endometrial cancer (n=1), and osteosarcoma (n=1). Based on the current evidence, the impact of HIFs should be heterogeneous on various human cancers.