Improving the Selectivity of PACE4 Inhibitors through Modifications of the P1 Residue
作者:Vahid Dianati、Pauline Navals、Frédéric Couture、Roxane Desjardins、Anthony Dame、Anna Kwiatkowska、Robert Day、Yves L. Dory
DOI:10.1021/acs.jmedchem.8b01381
日期:2018.12.27
Paired basic amino acid cleaving enzyme 4 (PACE4), a serine endoprotease of the proprotein convertases family, has been recognized as a promising target for prostate cancer. We previously reported a selective and potent peptide based inhibitor for PACE4, named the multi-Leu peptide (Ac-LLLLRVKR-NH2 sequence), which was then modified into a more potent and stable compound named C23 with the following structure: Ac-DLeu-LLLRVK-Amba (Amba: 4-amidinobenzylamide). Despite improvements in both in vitro and in vivo profiles of C23, its selectivity for PACE4 over furin was significantly reduced. We examined other Argmimetics instead of Amba to regain the lost selectivity. Our results indicated that the replacement of Amba with 5-(aminomethyl)picolinimidamide increased affinity for PACE4 and restored selectivity. Our results also provide a better insight on how structural differences between 51 pockets of PACE4 and furin could be employed in the rational design of selective inhibitors.