Angiogenesis is the physiological process through which new blood vessels form from pre-existing vessels, and is a normal and vital process in growth and development, as well as in wound healing and in granulation tissue. Angiogenesis is regulated by multiple factors, including growth and differentiative factors, extracellular matrix components, membrane-bound receptors, intracellular signaling molecules, and angiogenesis inhibitors. Several growth factors, including FGFs (fibroblast growth factors), VEGFs (vascular endothelial growth factors), PDGFs, eprins, angiopoietins, TGF-beta and other participate in regulating angiogenesis. Angiogenesis inhibitors can be endogenous or exogenous. Endogenous angiogenesis inhibitors may be interleukins, interferons, chemokines, or growth factor regulators.
In health, the body maintains a balance of angiogenesis regulators. However, the structures formed are often functionally abnormal, possibly due to an imbalance in the angiogenic process. Imbalance of angiogenesis stimulation and inhibition can lead to disease. In cancer, like tissues of the body, tumors need a blood supply. They get this through new blood vessel formation (angiogenesis). This is a fundamental step in the transition of tumors from a dormant state to a malignant one.
Selected Reviews:
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