Selective Allosteric Inhibition of MMP9 Is Efficacious in Preclinical Models of Ulcerative Colitis and Colorectal Cancer

Abstract

Expression of matrix metalloproteinase 9 (MMP9) is elevated in a variety of inflammatory and oncology indications, including ulcerative colitis and colorectal cancer. MMP9 is a downstream effector and an upstream mediator of pathways involved in growth and inflammation, and has long been viewed as a promising therapeutic target. However, previous efforts to target matrix metalloproteinases (MMPs), including MMP9, have utilized broad-spectrum or semi-selective inhibitors. While some of these drugs showed signs of efficacy in patients, all MMP-targeted inhibitors have been hampered by dose-limiting toxicity or insufficient clinical benefit, likely due to their lack of specificity. Here, we show that selective inhibition of MMP9 did not induce musculoskeletal syndrome (a characteristic toxicity of pan-MMP inhibitors) in a rat model, but did reduce disease severity in a dextran sodium sulfate-induced mouse model of ulcerative colitis. We also found that MMP9 inhibition decreased tumor growth and metastases incidence in a surgical orthotopic xenograft model of colorectal carcinoma, and that inhibition of either tumor- or stroma-derived MMP9 was sufficient to reduce primary tumor growth. Collectively, these data suggest that selective MMP9 inhibition is a promising therapeutic strategy for treatment of inflammatory and oncology indications in which MMP9 is upregulated and is associated with disease pathology, such as ulcerative colitis and colorectal cancer. In addition, we report the development of a potent and highly selective allosteric MMP9 inhibitor, the humanized monoclonal antibody GS-5745, which can be used to evaluate the therapeutic potential of MMP9 inhibition in patients.

Biochemical characterization and structure determination of a potent, selective antibody inhibitor of human MMP9

“…The distance between the nearest residue of GS-5745 (Thr-53 on CDR2 of the V H chain) to the active-site zinc of MMP9-procat is ϳ17 Å. GS-5745 does not occlude the active site ( Fig. 3B), consistent with its proposed allosteric mode of inhibition (19).…”

“…MMP9-pro-cat had been previously shown to contain the entire binding epitope recognized by the antibody (19). Diffraction-quality crystals yielded a 3.0-Å-resolution structure containing two well ordered FabЈ⅐MMP9-pro-cat complexes and a third disordered complex that could only be partially modeled ( Fig.…”

“…Although zinc-chelating small-molecule peptidomimetic MMP inhibitors were neither specific nor well tolerated in clinical trials (8 -10), a monoclonal antibody was identified that selectively inhibited MMP9 (19). This antibody and its humanized counterpart, GS-5745, were well tolerated and efficacious in preclinical models and human trials, respectively, of ulcerative colitis and cancer (19).…”

“…This antibody and its humanized counterpart, GS-5745, were well tolerated and efficacious in preclinical models and human trials, respectively, of ulcerative colitis and cancer (19). Although GS-5745 was shown to be an allosteric inhibitor of human MMP9 activity (19), the mechanisms of specificity and inhibition remained elusive. In the current studies, we determined the high-resolution crystal structure of MMP9 in complex with GS-5745.…”

Current and emerging therapeutic targets for IBD

“…Functional data in experimental models of inflammation have suggested an important role of MMP9 in impairing colonic epi thelial permeability and augmenting inflammation via activation of myosin light chain kinase (MLCK) 74 . Furthermore, MMP9 favoured angiogenesis and created a proteolytic environment in the inflamed gut of a mouse model of colitis that stimulated the influx of myeloid cells into the colonic epithelium and the prod uction of TNF 75,76 . Consecutively, a potent and highly selective allosteric MMP9 inhibitor (humanized mono clonal antibody GS 5745) has been developed and is currently being tested in clinical trials in patients with IBD 76 (FIG.…”