Hypoxia-inducible factor 1α in oral cancer

BACKGROUND: Hypoxia is a common feature of many cancers. It contributes to local and systemic tumour progression as well as potentially compromising radiotherapy and chemotherapy. Hypoxia-inducible factor 1 alpha (HIF-1 alpha) is an essential component in changing the transcriptional response of tumours under hypoxia. It targets the transcription of over 60 genes involved in many aspects of cancer biology including cell survival, glucose metabolism, cell invasion and angiogenesis. METHODS: In this review, we discuss the relevant literature on HIF-1 alpha with specific emphasis on oral cancer. We also present some of our preliminary data on HIF-1 alpha in oral cancer. RESULTS: Although there are a few conflicting reports of its prognostic significance, over expression of HIF-1 alpha seems to play an adverse role in the malignant progression of head and neck cancer by facilitating the adaptation of cells to hypoxia as well as contributing to the invasive properties and angiogenesis in these tumours. CONCLUSIONS: HIF-1 alpha has an important role to play in pathophysiology of oral cancer, both under normal and hypoxic conditions. The pharmacological manipulation of HIF-1 alpha has marked effects on tumour growth, and it could prove to be an important target for drug therapy, both in oral cancer and in other hypoxia-dependent disease states.