FigureĀ 1 The role of aspirin to tumor angiogenesis inhibition by regulation a balance of endogenous inhibitors andstimulators. (A) In the tumor microenvironment, the sum effect of these inhibitors and stimulants is angiogenesis with abnormal structure and function. This imbalance proangiogenic effects is aggravated by activated platelets, monocytes and macrophages. (B) Aspirin may reverse the balance of antiangiogenic and proangiogenic effect in angiogenesis through lower endogenous stimulators and boost inhibitors. Reverse of antiangiogenic and proangiogenic balance may inhibit angiogenesis, normalize existing blood vessels and reduce permeability and leakiness.
Abbreviations: TSP-1, thrombospondin-1; ZO-1, Zonula Occludens-1; VEGF, Vascular endothelial growth factor; FGF, Fibroblast growth factor; MMPs, matrix metalloproteinases; mTOR, Mammalian target of rapamycin.