original_query: What is the function of matrix metalloproteinases (MMPs) in degrading the extracellular matrix (ECM)?
query: What is the function of matrix metalloproteinases (MMPs) in degrading the extracellular matrix (ECM)?
answer: Matrix metalloproteinases (MMPs) are involved in the breakdown of the extracellular matrix (ECM) during normal physiological processes like embryonic development, reproduction, and tissue remodeling, as well as in disease processes such as arthritis and metastasis.  Most MMPs are secreted as inactive proproteins that are activated by cleavage.