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Potent, Selective, and Cell-Penetrating Inhibitors of Kallikrein-Related Peptidase 4 Based on the Cyclic Peptide MCoTI-II

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Specialty Chemistry
Date 2019 Jan 8
PMID 30613336
Citations 10
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Abstract

Kallikrein-related peptidase 4 (KLK4) is a serine protease that has putative intracellular and extracellular functions in prostate cancer progression. Here we show that MCoTI-II, a 34-amino acid cyclic peptide found in the seeds of red gac (), is an inhibitor of KLK4. By grafting a preferred KLK4 cleavage sequence into MCoTI-II, we produced a highly potent KLK4 inhibitor ( = 0.1 nM) that displayed 100,000-fold selectivity over related KLKs and the ability to penetrate cells. Additionally, by substituting positively charged noncontact residues in this compound, we produced a potent and selective KLK4 inhibitor that does not penetrate cells. The inhibitors were shown to be nontoxic to human cells and stable in human serum. These KLK4 inhibitors provide useful chemical tools to further define the role(s) of both intracellular and extracellular KLK4 in prostate cancer cell lines and disease models.

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References
1.
Luckett S, Garcia R, Barker J, Konarev A, Shewry P, Clarke A . High-resolution structure of a potent, cyclic proteinase inhibitor from sunflower seeds. J Mol Biol. 1999; 290(2):525-33. DOI: 10.1006/jmbi.1999.2891. View

2.
Daly N, Craik D . Circular proteins in plants: solution structure of a novel macrocyclic trypsin inhibitor from Momordica cochinchinensis. J Biol Chem. 2001; 276(25):22875-82. DOI: 10.1074/jbc.M101666200. View

3.
Heitz A, Hernandez J, Gagnon J, Hong T, Pham T, Nguyen T . Solution structure of the squash trypsin inhibitor MCoTI-II. A new family for cyclic knottins. Biochemistry. 2001; 40(27):7973-83. DOI: 10.1021/bi0106639. View

4.
Korsinczky M, Schirra H, Rosengren K, West J, Condie B, Otvos L . Solution structures by 1H NMR of the novel cyclic trypsin inhibitor SFTI-1 from sunflower seeds and an acyclic permutant. J Mol Biol. 2001; 311(3):579-91. DOI: 10.1006/jmbi.2001.4887. View

5.
Xi Z, Klokk T, Korkmaz K, Kurys P, Elbi C, Risberg B . Kallikrein 4 is a predominantly nuclear protein and is overexpressed in prostate cancer. Cancer Res. 2004; 64(7):2365-70. DOI: 10.1158/0008-5472.can-03-2025. View