MMP24

Matrix metalloproteinase-24 (MMP-24), also known as MT5-MMP, is a member of the matrix metalloproteinase family of zinc-dependent endopeptidases. As a membrane-type MMP, it is anchored to the cell surface and participates in pericellular proteolysis and remodeling of the extracellular matrix.

Structurally, MMP-24 contains the features common to many MMPs: an N-terminal signal peptide, a propeptide region that maintains the enzyme in an inactive zymogen form, a catalytic domain with the zinc-binding motif, and a hemopexin-like domain. It also possesses a transmembrane region that localizes the enzyme to the plasma membrane, aligning its proteolytic activity with the cell surface environment.

Activation of MMP-24 typically involves proteolytic removal of the prodomain, enabling catalytic activity. Its activity is regulated by endogenous inhibitors such as tissue inhibitors of metalloproteinases (TIMPs), as well as by cellular localization and transcriptional control.

MMP-24 is detected in a variety of human tissues, with notable expression reported in neural tissue and in certain cancer cell lines. In physiological contexts, it is thought to contribute to extracellular matrix remodeling during development, tissue repair, and other processes requiring controlled pericellular proteolysis. In cancer biology, elevated or misregulated MMP-24 expression has been associated with enhanced invasive potential in some tumors, highlighting a possible role in cancer progression and metastasis.

From a therapeutic perspective, the development of selective MMP-24 inhibitors has been challenging due to substrate overlap among MMPs and concerns about side effects observed with broad-spectrum MMP inhibitors. Research continues to clarify its specific substrates, regulation, and contributions to health and disease.