Figure 2From: Regulation of mammary gland branching morphogenesis by the extracellular matrix and its remodeling enzymesMechanism by which matrix metalloproteinases (MMPs) can affect branching morphogenesis. 1. Proteolytic digestion of extracellular matrix (ECM) would alter ECM-integrin tethering and ECM-integrin signalling [47-48]. 2. Cleavage of ECM may produce soluble ECM fragments containing morphogenic activity [49-54]. 3. ECM-sequestered factors may be released to produce morphogenic gradients or signalling [52-54]. 4. Loss of cell–cell adhesion molecules by MMPs would lead to epithelial-to-mesenchymal transition and increased invasiveness [55-57]. 5. Ligand or receptor shedding might initiate autocrine, juxtacrine, or paracrine morphogenic signalling [58-59].Back to article page