[Expression of matrix metalloproteinases in tumor cells]

Tumor cells have to degrade extracellular matrix components to invade surrounding tissue and to form metastatic colonies at distant organs. Matrix metalloproteinases are the enzymes that can degrade various types of native collagens and glycoproteins. In this study, we demonstrated the roles of matrix metalloproteinases in metastatic colony formation in chick embryo by transfecting TIMP-1 gene into a metastatic gastric cancer cell line, KKLS. The mechanism regulating expression of one of the type IV collagenases, MMP-9, was also studied using the promoter region of the gene.