Monday, March 14, 2011

Researchers illuminate laminin's role in cancer formation

Laminin, long thought to be only a structural support protein in the microenvironment of breast and other epithelial tissue, is “famous” for its cross-like shape. However, laminin is far more than just a support player with a “pretty face.” Two studies have shown how laminin plays a central role in the development of breast cancer. Mina Bissell, a "Distinguished Scientist" with the Lawrence Berkeley National Laboratory, is famous for having discovered the critical role in breast cancer development played by the extracellular matrix (ECM), the network of fibrous and globular proteins surrounding a breast cell. Her “dynamic reciprocity” theory holds that the fate of cells hinges on the chemical signals exchanged between the ECM and a cell’s nucleus. In these latest studies, Bissell and her collaborators focused on laminin and its connections with two other proteins—actin, a cytoplasmic protein that has been linked to nuclear activities; and MMP9, an enzyme that is secreted outside the cells and is known to break down ECM constituents. More>