HIF-1 alpha has been shown to
upregulate several genes to promote survival in hypoxic environments. Some of
the important genes that are upregulated are erythropoietin, nitric oxide
synthase (NOS), heme oxygenase 1 (HO-1), glucose transporters, and vascular
growth factors necessary for the maintenance of homeostasis in low oxygen
conditions. Oxygen-breathing species express this highly-conserved
transcriptional complex. The HIF-1 alpha expression also plays a role in cancer.
There is evidence that tumor hypoxia promotes metastasis through the induction
of MET overexpression by HIF-1 alpha. The mechanism of tumor hypoxia promoting
metastasis remains uncertain. HIF-1 alpha is a key mediator of the cellular
response to hypoxia and binds the met promoter, resulting in increased
expression of MET. In breast cancer, MET overexpression is associated with
metastatic disease and poor prognosis.