TGF beta: a sleeping giant awoken by integrins

Transforming growth factor beta (TGF beta) controls numerous cellular responses, including proliferation, differentiation, apoptosis and migration. This cytokine is produced by many different cell types and has been implicated in the pathogenesis of many diseases, ranging from autoimmune disorders and infectious diseases to fibrosis and cancer. However, TGF beta is always produced as an inactive complex that must be activated to enable binding to its receptor and subsequent function. Recent evidence highlights a crucial role for members of the integrin receptor family in controlling the activation of TGF beta. These pathways are important in human health and disease, and new insights into the biochemical mechanisms that allow integrins to control TGF beta activation could prove useful in the design of therapeutics.