MMP7

Matrix metalloproteinase-7 (MMP-7), also known as matrilysin, is a secreted zinc-dependent endopeptidase belonging to the matrix metalloproteinase family. It is one of the smaller MMPs and notably lacks the hemopexin-like domain that is present in many other family members. The MMP7 gene encodes the soluble enzyme that is produced as a latent proenzyme and activated by proteolytic removal of the pro-domain, a process that exposes the active site.

MMP-7 is expressed by epithelial cells in a range of tissues, including the gastrointestinal and respiratory tracts, among others. It is released into the extracellular milieu where it can act on a broad spectrum of substrates. Its substrates include components of the extracellular matrix such as proteoglycans, laminin, fibronectin, and various collagens, contributing to basement membrane and connective tissue remodeling. In addition to ECM components, MMP-7 can process non-matrix substrates and participate in processes such as development, wound healing, and mucosal defense.

Regulation of MMP-7 activity occurs at multiple levels. Its expression can be induced by inflammatory cytokines such as interleukin-1 and tumor necrosis factor, as well as growth factors. Activity is inhibited by tissue inhibitors of metalloproteinases (TIMPs), particularly TIMP-1, which binds the active enzyme and prevents substrate degradation.

Physiological and pathological roles are diverse. In normal physiology, MMP-7 participates in tissue remodeling and repair. Abnormal expression or activation has been linked to inflammatory diseases and cancer, where enhanced ECM degradation can promote invasion and metastasis in some tumor types. Because of its involvement in these processes, MMP-7 is a focus of research as a potential biomarker and therapeutic target, though broad MMP inhibitors have faced clinical development challenges.