Certain normally extracellular MMPs can transiently localize at the cell periphery in association with adhesion receptors or proteoglycans. ProMMP9, MMP9, MMP2 and MMP7 (Ahmed et al. 2002, Samanna et al. 2006, Yu et al. 2002) localize at the cell membrane with the single-pass transmembrane glycoprotein CD44, known to be involved in hyaluronan-cell interactions, lymphocyte homing and cell adhesion (Toole 1990). Membrane-associated MMP7 can bring about the shedding of several membrane proteins such as epidermal growth factor (EGF), soluble Fas ligand (FasL), E-cadherin and TNF-alpha from their membrane-bound precursors, thereby promoting cancer progression (Li et al. 2006). MMP9 is able to cleave CD44, inhibiting cell migration and reducing the malignant potential of tumour cells (Chetty et al. 2012).