Matrix metalloproteinases and their role in oncogenesis: a review.

The extracellular matrix (ECM) provides a physical framework for the cells and functions as a gel medium. Remodeling of the ECM is crucial during physiological cell migration, proliferation, growth, and development. Thus, the interaction between cells and the ECM plays a key role in normal development and differentiation of organisms. However, remodeling of the ECM also occurs in many pathological states. Changes in the ECM are regulated by a system of proteolytic enzymes that are responsible for the proteolysis of a huge quantity of ECM components. Matrix metalloproteinases (MMPs) represent the main group of regulating proteases in the ECM. By regulating the composition and integrity of the ECM, this group of enzymes is essential for cell proliferation, differentiation, and processes of apoptosis. However, deregulation or activation of MMP expression is a feature of numerous pathologic conditions including tumorigenesis and metastasis. The aim of this article is to provide a brief overview of MMPs, their nomenclature and structure, and their role in the development of tumors and metastases.