Angiogenic mechanisms endothelial cell proliferation

The technologies described above can be used to pinpoint the mechanism(s) of action of angiogenic or angiostatic agents in specific steps in the angiogenic cascade. For instance, application of these systems revealed that IFNa and angiostatin inhibit cell migration whereas endostatin and platelet factor-4 function primarily as inhibitors of endothelial cell proliferation. 

The angiogenic switch, which leads endothelial cells from a quiescent state to active proliferation, occurs when the subtle balance between angiogenic stimulators and inhibitors is altered. While the exact mechanism of the angiogenic switch is still not fully understood, so far, four components have been proposed or identified to play roles in angiogenic switch in tumorigenesis, based on the studies. (1) Tumor angiogenesis driven by the prevascular tumors. The diffusion... 

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