The role of metalloproteinases in breast lesions

During the last decades, increasing attention has been focused on the role of extracellular matrix, especially basement membrane, in the process of tumor invasion and metastasis. Although the bio-chemical mechanisms involved in basement membrane turnover under physiological conditions remain essentially unknown, it has been established that the basement membrane-degrading proper-ties of tumor cells correlate with their metastatic potential. Degrada-tion of extracellular matrices is a fundamental stage in the process of invasion and the development of metastasis. Matrix metalloproteinases (MMPs) are a group of proteolytic enzymes with capacity to degrade and remodel the components of the extracellular matrix. These MMPs include collagenases, gelati-nases, stromelysins and others. The activity of these enzymes depends on many factors, including the presence of specific in-hibitors of metalloproteinases or TIMPs