An Overview of Heterologous Expression Host Systems for the Production of Recombinant Proteins

M atrix metalloproteinases (MMPs) encompasses a family of secreted, calcium dependent, zinc containing endopeptidases.These enzymes are responsible for tissue remodelling and are capable of degrading all kinds of extracellular matrix proteins including collagens, matrix glycoproteins, gelatin, elastins, and proteoglycans.MMPs are involved in regulation of cell behaviours like cellular differentiation, proliferation, angiogenesis, invasion, and apoptosis.Thus, these enzymes have multi-factorial roles during tumor progression: promoting establishment, tumor cell exfoliation, invasion and angiogenesis.The degra-dation of extracellular matrix components is crucial for tumor cell invasion and MMPs, especially MMP2 (72 kDa gelatinase A) and MMP9 (92 kDa gelatinase B), play critical role in degradation of gelatin and type IV collagen, the two major constituents of extracellular matrix.MMP9 and MMP2 are involved in invasion and metastases of many human cancers such as cancers of colon (Karakiulakis et al.,