TGF-beta in the cardiovascular system: molecular mechanisms of a context-specific growth factor.

Transforming growth factor beta-1 is the prototypical member of a class of growth factors whose actions have been strongly implicated in a number of pathophysiologic processes including chronic vascular diseases such as atherosclerosis and hypertension. One of the hall-marks of this class of growth factors is the diverse nature of their actions; a characteristic that is thought to arise from the fact that the effects of these factors are very dependent upon the particular cellular context in which they operate. There has been substantial progress in understanding the molecular signaling mechanisms utilized by these factors. These findings are beginning to provide a mechanistic framework with which to understand the complex and pleiotropic actions of these factors on cells and tissues of the cardiovascular system.