RESUMEN
Collagenase-3 (MMP-13) is characterized by an exceptionally wide substrate specificity and restricted expression. MMP-13 is 1 of the few MMPs primarily expressed by tumor cells in malignant tumors, e.g., squamous cell carcinomas and its expression correlates with their invasion capacity. In this work, we have constructed an expression vector and a recombinant adenovirus harboring human MMP-13 cDNA to investigate the role of MMP-13 in cancer cell invasion. Our results show that constitutive expression of MMP-13 by HT-1080 cells stably transfected with MMP-13 expression vector or transduced with MMP-13 adenovirus markedly increased their invasion both through type I collagen and reconstituted basement membrane (Matrigel) with no alterations in expression or activation of collagenase-1 (MMP-1), gelatinase-A (MMP-2), or gelatinase-B (MMP-9). The enhanced invasion capacity of MMP-13 expressing HT-1080 cells was dependent on MMP activity, as it was blocked by MMP inhibitor Batimastat (BB-94) and tissue inhibitor of metalloproteinases-3 (TIMP-3). Our data provide direct evidence for the role of MMP-13 as a potent invasion proteinase, which alone can enhance the ability of malignant cells to penetrate through both basement membrane and fibrillar collagen.