Design, synthesis and biological evaluation of phosphopeptides as Polo-like kinase 1 Polo-box domain inhibitors
Design, synthesis and biological evaluation of phosphopeptides as Polo-like kinase 1 Polo-box domain inhibitors
复制标题
作为 Polo 样激酶 1 Polo-box 结构域抑制剂的磷酸肽的设计、合成和生物学评价
DOI：
10.1016/j.bmc.2018.05.014
复制
发表时间：
2018
影响因子：
3.5
通讯作者：
Di Bin
中科院分区：
文献类型：
--
作者：
Lin Tong-yuan;Min Hong-ping;Jiang Cheng;Niu Miao-miao;Yan Fang;Xu Li-li;Di Bin
Polo样激酶1（Plk 1）是一种抗癌靶点，因为它在有丝分裂过程中起着关键作用。越来越多的证据证明肽-Plk 1抑制剂显示出高的Plk 1结合亲和力。然而，磷酸肽-Plk 1抑制剂表现出较差的细胞膜通透性，这限制了它们的临床应用。本研究采用Fmoc-固相肽合成（SPPS）策略，合理设计并成功合成了9个非天然氨基酸组成的候选磷酸肽。此外，通过荧光偏振（FP）测定评价结合亲和力和选择性。结果表明，最有希望的磷酸肽6与Plk 1 PBD结合的IC 50为38.99 nM，其选择性约为Plk 3 PBD的600倍（IC 50 = 25.44 μM），而与Plk 2 PBD几乎不结合。并测定了磷酸肽6的细胞内活性和细胞膜通透性。磷酸肽6通过调节CyclinB 1-CDK 1的表达，使HeLa细胞周期阻滞于G2/M期。此外，磷酸肽6显示典型的凋亡形态，并诱导caspase依赖性凋亡。总之，我们希望我们的发现可以为Plk 1 PBD抑制剂的进一步优化提供新的见解。
Polo-like kinase 1 (Plk1) is an anti-cancer target due to its critical role in mitotic progression. A growing body of evidence has documented that Peptide-Plk1 inhibitors showed high Plk1 binding affinity. However, phosphopeptides-Plk1 inhibitors showed poor cell membranes permeability, which limits their clinical applications. In current study, nine candidate phosphopeptides consisting of non-natural amino acids were rationally designed and then successfully synthesized using an Fmoc-solid phase peptide synthesis (SPPS) strategy. Moreover, the binding affinities and selectivity were evaluated via fluorescence polarization (FP) assay. The results confirmed that the most promising phosphopeptide6bound to Plk1 PBD with the IC50of 38.99 nM, which was approximately 600-fold selectivity over Plk3 PBD (IC50= 25.44 μM) and nearly no binding to Plk2 PBD. Furthermore the intracellular activities and the cell membrane permeability of phosphopeptide6were evalutated. Phosphopeptide6demonstrated appropriate cell membrane permeability and arrested HeLa cells cycle in G2/M phase by regulating CyclinB1-CDK1. Further, phosphopeptide6showed typical apoptotic morphology and induced caspase-dependent apoptosis. In conclusion, we expect our discovery can provide new insights into the further optimization of Plk1 PBD inhibitors.