title: Inhibition of enzyme activity of and cell-mediated substrate cleavage by membrane type 1 matrix metalloproteinase by newly developed mercaptosulphide inhibitors.
abstract: MT1-MMP (membrane type 1 matrix metalloproteinase, or MMP-14) is a key enzyme in molecular carcinogenesis, tumour-cell growth, invasion and angiogenesis. Novel and potent MMP inhibitors with a mercaptosulphide zinc-binding functionality have been designed and synthesized, and tested against human MT1-MMP and other MMPs. Binding to the MT1-MMP active site was verified by the competitive-inhibition mechanism and stereochemical requirements. MT1-MMP preferred deep P1' substituents, such as homophenylalanine instead of phenylalanine. Novel inhibitors with a non-prime phthalimido substituent had K(i) values in the low-nanomolar range; the most potent of these inhibitors was tested and found to be stable against air-oxidation in calf serum for at least 2 days. To illustrate the molecular interactions of the inhibitor-enzyme complex, theoretical docking of the inhibitors into the active site of MT1-MMP and molecular minimization of the complex were performed. In addition to maintaining the substrate-specificity pocket (S1' site) van der Waals interactions, the P1' position side chain may be critical for the peptide-backbone hydrogen-bonding network. To test the inhibition of cell-mediated substrate cleavage, two human cancer-cell culture models were used. Two of the most potent inhibitors tested reached the target enzyme and effectively inhibited activation of proMMP-2 by endogenous MT1-MMP produced by HT1080 human fibrosarcoma cells, and blocked fibronectin degradation by prostate cancer LNCaP cells stably transfected with MT1-MMP. These results provide a model for mercaptosulphide inhibitor binding to MT1-MMP that may aid in the design of more potent and selective inhibitors for MT1-MMP.
authors: Department of Chemistry and Biochemistry and Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4390, USA.
authors: Douglas R
authors: DR
authors: Hurst
authors: Martin A
authors: MA
authors: Schwartz
authors: Yonghao
authors: Y
authors: Jin
authors: Mohammad A
authors: MA
authors: Ghaffari
authors: Pallavi
authors: P
authors: Kozarekar
authors: Jian
authors: J
authors: Cao
authors: Qing-Xiang Amy
authors: QX
authors: Sang
mesh_terms: D001667:Binding, Competitive; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D006801:Humans; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D053504:Matrix Metalloproteinases, Membrane-Associated; D008958:Models, Molecular; D015394:Molecular Structure; D011480:Protease Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding; D013379:Substrate Specificity; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D013438:Sulfhydryl Compounds; D020782:Matrix Metalloproteinases; D053504:Matrix Metalloproteinases, Membrane-Associated