MMP-1 is a member of matrix metalloproteinase family proteins (MMPs); members of this family are structurally related, zinc-containing enzymes that degrade the extracellular matrix (ECM) and connective tissue proteins.? MMP-1 consists of a prodomain which is cleaved upon activation: a catalytic domain containing the zinc binding site, a short hinge region, and a carboxyl terminal (hemopexin-like repeats) domain. Substrates of MMP-1 include collagen I, II, III, VII, VIII, and X as well as casein, gelatin, alpha1 antitrypsin, myelin basic protein, L Selectin, pro-TNF, IL-1β, IGFBP3, IGFBP5, pro-MMP-2, and pro-MMP-9. In addition, chemokines are substrates for MMP-1. CCL2, CCL7, CCL8, and CCL13 are catalytically cleavage by MMP-1 to produce receptor antagonists. CXCL5 and CXCL12 are also substrates for MMP-1. TIMPs inhibit MMPs in a 1:1 inhibitor to enzyme ratio through interaction of the N-terminal domain of the TIMP molecule with the active site of the MMP. MMPs are involved in the breakdown of ECM in normal physiological processes, such as embryonic development, reproduction, and tissue remodeling as well as in disease processes such as arthritis and metastasis. MMP-1 is overexpressed in invasive melanoma, colorectal, and esophageal cancers. Importantly, MMP-1 expression was shown to increase progressively with tumor stage.