Macrophages accumulate in poorly vascularised and hypoxic sites including solid tumours,
wounds and sites of
infection and
inflammation where they can be exposed to low levels of
oxygen for long periods. Up to date, different studies have shown that a number of
transcription factors are activated by
hypoxia which in turn activate a broad array of mitogenic, pro-invasive, pro-angiogenic, and pro-metastatic genes. On the other hand, macrophages respond to
hypoxia by up-regulating several genes which are chief factors in angiogenesis and
tumorigenesis. Therefore, in this review article we focus mainly on the role of macrophages during
inflammation and discuss their response to
hypoxia by regulating a diverse array of
transcription factors. We also review the existing literatures on
hypoxia and its cellular and molecular mechanism which mediates macrophages activation.