非ATP竞争性的IKK-β抑制剂的设计发现及其药理活性研究

IKK-β is a key regulator of transcriptional factor NF-κB and plays an important role in a number of diseases. Inhibition of IKK-β significantly attenuates inflammation and tumor development. Currently, several small molecule IKK-β inhibitors have been reported in an ATP-competitive pattern and are under clinical or preclinical investigation. However, they exhibit the common disadvantages of ATP-competitive inhibitors, for example, low selectivity, side effects, and easily affected by high ATP concentration. In the past several years, our group carried out the medicinal chemistry and pharmacology research on curcumin-based anti-inflammatory agents. Previously, we have found the new curcumin analogs A13 and C12 could inhibit IKK-β by non-ATP-competitive pattern and exerted the anti-inflammatory effects. We hypothesize here, that understanding the A13/C12-IKK-β binding mechansm and taking A13/C12 as the leads, we may design and find novel non-ATP-competitive IKK-β inhibitors. In this project, we plan to demonstrate the binding mechanism of IKK-β and A13/C12, and design and synthesis a series of compounds by A13/C12-based computer-assistant drug design as well as perform their anti-inflammatory and anti-tumor evaluation both in vitro and in vivo. This study will provide the new structural inflammation, binding mode, and lead for IKK-β-targeting agents for the therapy of inflammation and cancer.

IKK-β是调节转录因子NF-κB活性的重要激酶，在多种疾病中有着重要作用。抑制IKK-β可以显著缓解炎症和肿瘤。目前已发现多个IKK-β的ATP竞争性小分子抑制剂。但是，它们存在着ATP竞争性抑制剂的普遍缺点：激酶选择性差、副作用大、体内高ATP浓度易致失效等。本课题组长期从事以姜黄素为先导的抗炎药物化学和药理研究，前期工作中发现类似物A13和C12通过非ATP竞争性的方式抑制IKK-β磷酸化而产生良好的抗炎作用。我们假设：通过以A13和C12为先导，深入了解其与IKK-β的结合模式和机制，有望设计和发现新的非ATP竞争性的IKK-β抑制剂。本项目拟通过系列酶学研究深入阐明A13\C12与IKK-β的结合机制；以A13\C12等类似物为先导基于蛋白结构分子对接设计合成一系列类似物并进行抗炎测试和体内外药理研究。本研究将为IKK-β为靶点炎症和肿瘤药物设计提供新的结构先导和作用模式。

为了设计和发现新的非ATP竞争性的IKK-β抑制剂，本研究以A13\C12 等类似物的关键结构为基础，设计并合成了二取代嘧啶类，嘌呤类和噻吩并嘧啶类三类化合物，共合成170个化合物，所合成的化合物均通过质谱，核磁，红外等方法确证。为了更好地研究化合物对IKK-β靶点的作用，我们做了前期活性测试工作，对化合物进行抗炎活性和抗肿瘤筛选，结果显示：化合物C7、C10、C19对野生型和突变型均具非常好的活性，其野生型的IC50值分别为27.0 nM, 27.3 nM和37.5 nM， 对EGFRL858R突变型的IC50值分别为10.5 nM, 7.1 nM和12.5 nM，对EGFRd746-750突变型的IC50值分别为18.7 nM，21.6 nM和31.6 nM，EGFRT790M突变型的IC50值分别为1.1 nM,1.0 nM和0.9 nM。值得注意的是化合物A15，B10，B23，B25，C26和D22对EGFR野生型活性不好，而对EGFR突变型EGFRL858R和EGFRd746-750活性较好，这些化合物对野生型EGFR的IC50值均大于20000 nM，而化合物D22对EGFRL858R和EGFRd746-750的IC50值分别为684.8 nM和1352.5 nM；化合物A15对EGFRL858R和EGFRd746-750的IC50值分别为754.0 nM和1209.4 nM。