Hypoxia-inducible factor (HIF) activates the transcription of genes that are involved in crucial aspects of cancer biology, including angiogenesis, cell survival, glucose metabolism and invasion.HIF-1α protein synthesis is regulated by activation of the phosphatidylinositol 3-kinase (PI3K) and ERK mitogen-activated protein kinase (MAPK) pathways. Then AKT, mTOR and p70 S6 kinase (S6K) are phosphorylated resulting in the inhibition of cap-dependent mRNA translation through binding of 4E-BP1 to eIF-4E. The effect of growth-factor signalling is an increase in the rate at which a subset of mRNAs within the cell (including HIF-1α mRNA) is translated into protein.
