infiltration assays revealed that minor structural modifications have significant effects on the ability of our PIs to inhibit intracellular proteasomes, and we identified 5k as a promising candidate for continued therapeutic studies. Our novel drug lead 5k is a more potent proteasome inhibitor than carfilzomib with mid-to-low nanomolar IC50 measurements and it is cytotoxic against multiple cancer cell lines
肽β-内酯
蛋白酶体
抑制剂(
PIs)胱
氨酸A和B被用于进行结构活性关系(
SAR)研究,以评估其抗癌潜力。总共设计,合成并评估了24种不同的类似物的
蛋白酶体抑制作用,对几种癌
细胞系的细胞毒性以及它们进入完整细胞的能力。X射线晶体学分析和亚基选择性用于确定与β-内酯(P 1),肽核,(P x和P y)和端帽(P z)的结构修饰相关的特定亚基结合我们的脚手架。cygogolide衍
生物5k,在P y和P处结构唯一图1显示出对人
蛋白酶体的β5亚基最有希望的抑制活性(IC 50 = 3.1nM),并且对MCF-7(IC 50 = 416nM),
MDA-MB-231(IC 50 = 74nM)和对MCF-7具有显着的细胞毒性。RPMI 8226(IC 50 = 41 nM)癌
细胞系。细胞浸润试验表明,微小的结构修饰对我们的
PI抑制细胞内
蛋白酶体的能力有重大影响,我们确定5k是继续治疗研究的有希望