Table 6.
Characteristics of MMPs associated with BC development.
| Gene | Gene Localised | Name (Aliases) | Location | Substrates | Activation Pathway | References |
|---|---|---|---|---|---|---|
| MMP-1 | 11q22.2 | interstitial collagenase (CLG, CLGN) | secreted | collagens: I, II, III, VII, VIII, X, gelatin | The plasmin has been described and other serine proteases, i.e., kallikrein, trypsin, neutrophil elastase, cathepsin G, tryptase and chymase may be involved in the activation of proMMP-1. | [293,294] |
| MMP-2 | 16q12.2 | gelatinase-A, 72 kDa gelatinase | secreted | gelatin, collagens: I, II, III, IV, Vii, X | A complex of membrane-type 1 MMP (MT1-MMP/MMP14) and tissue inhibitor of MMP-2 recruits pro-MMP 2 from the extracellular milieu to the cell surface. Activation then requires an active molecule of MT1-MMP and autocatalytic cleavage. Clustering of integrin chains promotes MMP-2 activation. Another factor that will support the activation of MMP-2 is cell-cell clustering. A wild-type activated leukocyte cell adhesion molecule (ALCAM) is also required to activate the MMP-2. | [146,147,293,295,296,297,298,299,300,301,302,303,304,305,306] |
| MMP-7 | 11q22.2 | matrilysin, PUMP 1 (MMP-7, MPSL-1, PUMP-1) | secreted | fibronectin, laminin, collagen IV, gelatin | Pro-MMP7 is converted from the latent form to the active form by endoproteinases and plasmin. Plasmin cleaves at the site recognisable to trypsin is considered as the possible physiological activator. | [299,307] |
| MMP-9 | 20q13.12 | gelatinase-B, 92 kDa gelatinase (CLG4B, GELB, MANDP2, MMP-9) | secreted | gelatin, collagen IV, V | The proMMP-9 includes a cysteine residue in the N-terminal pro-domain that binds to the zinc atom in the active site thus maintaining latency. Activation of MMP-9 requires a disruption of the cysteine interaction with the zinc atom. MMP-9 activators include MMP-2, MMP-3, MMP-7, MMP-10, MMP-13, cathepsin G and urokinase/plasmin. | [296,297,298,299,304] |
| MMP12 | 11q22.2 | macrophage metalloelastase (HME, ME, MME, MMP-12) | secreted | elastin, fibronectin, collagen IV | Neutrophil elastase may be required for the proteolytic activation of pro-MMP-12 | [304] |