The Matrix Metalloproteinase (MMP) family of enzymes are involved in both normal and diseased tissue remodeling. MMPs are endopeptidases, which cleave metabolic peptides, thereby altering their properties. These enzymes are key in the migration of normal and malignant cells through the body. They regulate biological effects by processing cell matrix proteins, cytokines, growth factors, and adhesion molecules. As many as 10 to 20 MMPs may be involved in such regulation, so multiplexing these assays is ideal using xMAP technology.