Angiogenesis Monitoring

Pharmacological Modulation of Angiogenesis.

Angiogenesis (vascularization) is the physiological process through which new capillary blood vessels are formed in the body. Angiogenesis plays an essential role in normal development, reproduction, and the formation of granulation tissue and wound healing. However, when angiogenesis is dysregulated, new blood vessels grow excessively or insufficiently, resulting in diseases such as, cancer, diabetic blindness, age related macular degeneration, rheumatoid arthritis, coronary artery disease, stroke, circulatory related conditions, and other diseases. Monitoring and understanding how to control angiogenesis stimulators and inhibitors has become a fundamental part in the development of new medicines and therapeutic techniques. “While angiogenesis is a critical part of wound healing and other favorable processes, certain types of angiogenesis are associated with the growth of malignant tumors. Thus angiogenesis inhibitors have been closely studied for possible cancer treatment. Angiogenesis inhibitors were once thought to have potential as a “silver bullet” treatment applicable to many types of cancer, but the limitations of anti-angiogenic therapy have been shown in practice. Nonetheless, inhibitors are used to effectively treat cancer, macular degeneration in the eye, and other diseases that involve a proliferation of blood vessels.

When a tumor stimulates the growth of new vessels, it is said to have undergone an ‘angiogenic switch’. The principal stimulus for this angiogenic switch appears to be oxygen deprivation, although other stimuli such as inflammation, oncogenic mutations and mechanical stress may also play a role. The angiogenic switch leads to tumor expression of pro-angiogenic factors and increased tumor vascularization. Specifically, tumor cells release various pro-angiogenic paracrine factors (including angiogenin, vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and transforming growth factor-β (TGF-β). These stimulate endothelial cell proliferation, migration and invasion resulting in new vascular structures sprouting from nearby blood vessels. Cell adhesion molecules, such as integrins, are critical to the attachment and migration of endothelial cells to the extracellular matrix” (NIH).