DeClerck Y A, Perez N, Shimada H, Boone T C, Langley K E, Taylor S M
Department of Pediatrics, University of Southern California, Los Angeles 90033.
Cancer Res. 1992 Feb 1;52(3):701-8.
The balance between levels of metalloproteinases and their corresponding inhibitors is a critical factor in tumor invasion and metastasis. Down-regulation of the activity of these proteases was achieved by transfection of invasive and metastatic rat cells with the complementary DNA for metalloproteinase inhibitor/tissue inhibitor of metalloproteinase 2 (MI/TIMP-2), a novel inhibitor of metalloproteinases recently described. (Y. A. DeClerck et al., J. Biol. Chem., 264: 17445-17453, 1989; W. G. Stetler-Stevenson et al., J. Biol. Chem., 264: 17374-17378, 1989). Secretion of functional MI/TIMP-2 protein in stably transfected cells resulted in a marked decrease in metalloproteinase activity. Partial suppression of the formation of lung colonies after i.v. injection in nude mice was observed in a transfected clone expressing high levels of MI/TIMP-2. Production of MI/TIMP-2 in four clones markedly reduced tumor growth rate in vivo after s.c. injection and completely suppressed local tissue invasion. Thus, down-regulation of metalloproteinase activity has a striking effect on local invasion and partially suppresses hematogenous metastasis.
