Matrix metalloproteinases in skin pathology (Review).

Human tissue is composed in part of cells and in part of amorphous matrix components. Equilibrium exists between the synthesis and degradation of connective tissue under physiological conditions, which serves both the formation and the maintenance of tissue architecture. Synthesis progresses via mesenchymal cells, degradation is controlled by the proteolytic effect of a group of enzymes, which belong to the protein family of matrix metalloproteinases. In biological development, matrix metalloproteinases play an important role in all essential configurative processes in embryo- and histogenesis. As a result of the importance of matrix metalloproteinases in creation of connective tissue, dysregulation with excessive proteolytic activity may result in tissue damage. Histological structural changes are set in relation to the molecular expression pattern of matrix metalloproteinases using matrix relevant diseases of human skin. Discussion includes fibrosing processes, skin inflammations, wound healing, blistering diseases, premature sun-induced skin aging and primary cutaneous malignomas and their metastases.