α-Ketobenzothiazole Serine Protease Inhibitors of Aberrant HGF/c-MET and MSP/RON Kinase Pathway Signaling in Cancer.

Upregulation of the HGF and MSP growth-factor processing serine endopeptidases HGFA, matriptase and hepsin is correlated with increased metastasis in multiple tumor types driven by c-MET or RON kinase signaling.

We rationally designed P1' α-ketobenzothiazole mechanism-based inhibitors of these proteases. Structure-activity studies are presented, which resulted in the identification of potent inhibitors with differential selectivity. The tetrapeptide inhibitors span the P1-P1' substrate cleavage site via a P1' amide linker off the benzothiazole, occupying the S3' pocket. Optimized inhibitors display sub-nanomolar enzyme inhibition against one, two, or all three of HGFA, matriptase, and hepsin. Several compounds also have good selectivity against the related trypsin-like proteases, thrombin and Factor Xa. Finally, we show that inhibitors block the fibroblast (HGF)-mediated migration of invasive DU145 prostate cancer cells. In addition to prostate cancer, breast, colon, lung, pancreas, gliomas, and multiple myeloma tumors all depend on HGF and MSP for tumor survival and progression. Therefore, these unique inhibitors have potential as new therapeutics for a diverse set of tumor types.

ChemMedChem. 2016 Feb 17 [Epub ahead of print]

Zhenfu Han, Peter K W Harris, Partha Karmakar, Tommy Kim, Ben Y Owusu, Scott A Wildman, Lidija Klampfer, James W Janetka

Department of Biochemistry and Molecular Biophysics, Alvin J. Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Ave. , Saint Louis, MO, 63110, USA. , Department of Biochemistry and Molecular Biophysics, Alvin J. Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Ave. , Saint Louis, MO, 63110, USA. , Department of Biochemistry and Molecular Biophysics, Alvin J. Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Ave. , Saint Louis, MO, 63110, USA. , Department of Biochemistry and Molecular Biophysics, Alvin J. Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Ave. , Saint Louis, MO, 63110, USA. , Department of Oncology, Southern Research Institute, 2000 9th Ave. , Birmingham, AL, 35205, USA. , Department of Biochemistry and Molecular Biophysics, Alvin J. Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Ave. , Saint Louis, MO, 63110, USA. , Department of Oncology, Southern Research Institute, 2000 9th Ave. , Birmingham, AL, 35205, USA. , Department of Biochemistry and Molecular Biophysics, Alvin J. Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Ave. , Saint Louis, MO, 63110, USA.

PubMed