There are currently 23 recognised MMPs expressed in the human proteome. MMPs and their substrates are widely expressed in many tissues, and are required for various homeostatic functions, such as tissue remodeling, wound healing and immunity. Accumulating evidence indicates that in addition to their role in degrading extracellular matrix components, MMPs are also involved in cleaving and activating a variety of non-matrix proteins, including cytokines, chemokines and growth factors. Under normal circumsatnces their expression and activity is tightly regulated by specific activators and inhibitors. However, aberrant function of any of these factors results in dysregulated MMP activity, and has been recognised in many pathological conditions, including cardiovascular disease, arthritis, neurodegenerative disease, and cancer. The contribution of MMPs in non-neoplastic pathology is reviewed by Tokito and Jougasaki (2016) [3]. MMP involvement in tumour invasion and metastasis is reviewed by Brown and Murray (2015) [1], and progress towards development of selective MMP inhibitors with anti-cancer potential is presented in [2] (King, 2016).

Figure 1. Classification and structure of human MMPs Image from Tokito and Jougasaki (2016) [3]

1. Brown GT, Murray GI. (2015) Current mechanistic insights into the roles of matrix metalloproteinases in tumour invasion and metastasis. J Pathol, 237 (3): 273-81. [PMID:26174849]

2. King SE. (2016) Matrix metalloproteinases: new directions toward inhibition in the fight against cancers. Future Med Chem, 8 (3): 297-309. [PMID:26910530]

3. Tokito A, Jougasaki M. (2016) Matrix Metalloproteinases in Non-Neoplastic Disorders. Int J Mol Sci, 17 (7). [PMID:27455234]