The biology of the extracellular matrix: novel insights

Purpose of review Extracellular matrix (ECM) has both structural and regulatory roles. This update reviews the representative recent developments in diverse aspects of ECM biology relevant to inflammation, tissue destruction, fibrosis, and regeneration. Recent findings Biological regulation by ECM is emerging as a major research area, driven by several new directions. Sensing of mechanical cues provided by ECM was found to be crucial in regulating cell differentiation. Transforming growth factor-beta (TGF-beta) is a pivotal agent in fibrosis and inflammation. A combination of structural biology and cell biology provided novel insights on the mechanisms of its activation by cellular traction and ECM. Improved understanding of how fibrillin microfibrils and associated proteins regulated TGF-b sequestration and activation was achieved by analysis of inherited connective tissue disorders having TGF-b dysregulation as an underlying pathologic mechanism. Insights on microRNA-mediated ECM regulation suggest a key role for miR-29, for which potential therapeutic roles are emerging. Advances in understanding the ECM turnover by proteinases provided novel insights on cell regulation and identified useful disease biomarkers. Summary As a crucial modulator of cell behavior, ECM has exceptionally strong relevance and translational implications for human disease, opening novel opportunities for mechanistic understanding of disease pathogenesis as well as treatment.