Signaling in Normal and Pathological Angiogenesis

Abstract

Angiogenesis, the growth of new blood vessels from pre-existing ones, is crucial for the growth and development of many multicellular organisms and for the progression of many diseases such as cancer, macular degeneration, and diabetic retinopathy. The process of angiogenesis begins with a combination of highly controlled endothelial cell migration (tip cell phenotype) and proliferation (stalk cell phenotype) to form new immature blood vessels. These newly formed blood vessels, also termed “neovessels,” are then stabilized through recruitment of mural cells to generate a mature vascular network that is required for the metabolic demands of the underlying tissue, and provides a conduit through which the immune system functions. A delicate balance between positive and negative angiogenic regulators governs this complex process. In this chapter we will focus on the key signaling events that regulate angiogenesis both during development and in disease.