Lund George, Dudkin Sergii, Borkin Dmitry, Ni Wendi, Grembecka Jolanta, Cierpicki Tomasz
Department of Pathology, University of Michigan , 4510C MSRBI 1150 West Medical Center Drive, Ann Arbor, Michigan 48109-5620, United States.
ACS Chem Biol. 2015 Feb 20;10(2):390-4. doi: 10.1021/cb500883h. Epub 2014 Dec 1.
CDC25 phosphatases are key cell cycle regulators and represent very attractive but challenging targets for anticancer drug discovery. Here, we explored whether fragment-based screening represents a valid approach to identify inhibitors of CDC25B. This resulted in identification of 2-fluoro-4-hydroxybenzonitrile, which directly binds to the catalytic domain of CDC25B. Interestingly, NMR data and the crystal structure demonstrate that this compound binds to the pocket distant from the active site and adjacent to the protein-protein interaction interface with CDK2/Cyclin A substrate. Furthermore, we developed a more potent analogue that disrupts CDC25B interaction with CDK2/Cyclin A and inhibits dephosphorylation of CDK2. Based on these studies, we provide a proof of concept that targeting CDC25 phosphatases by inhibiting their protein-protein interactions with CDK2/Cyclin A substrate represents a novel, viable opportunity to target this important class of enzymes.
细胞周期蛋白磷酸酶25（CDC25）是关键的细胞周期调节因子，是抗癌药物研发中极具吸引力但也颇具挑战性的靶点。在此，我们探究了基于片段的筛选是否是鉴定细胞周期蛋白磷酸酶25B（CDC25B）抑制剂的有效方法。这导致了2-氟-4-羟基苯甲腈的鉴定，它直接与CDC25B的催化结构域结合。有趣的是，核磁共振（NMR）数据和晶体结构表明，该化合物结合在远离活性位点且与细胞周期蛋白依赖性激酶2（CDK2）/细胞周期蛋白A底物的蛋白质-蛋白质相互作用界面相邻的口袋中。此外，我们开发了一种更有效的类似物，它破坏了CDC25B与CDK2/细胞周期蛋白A的相互作用，并抑制了CDK2的去磷酸化。基于这些研究，我们提供了一个概念验证，即通过抑制CDC25磷酸酶与CDK2/细胞周期蛋白A底物的蛋白质-蛋白质相互作用来靶向这类重要的酶是一种新的可行机会。
