Small Molecule Activators of Pro-apoptotic BAX for Cancer Therapy

描述（由申请人提供）：靶向关键凋亡调节剂以克服癌细胞的凋亡抗性是一种非常有吸引力的治疗策略。BCL-2蛋白 该家族包括促凋亡蛋白和抗凋亡蛋白，它们形成复杂的相互作用网络，调节细胞生命和死亡之间的关键平衡。BAX是一种促凋亡BCL-2成员，其在激活时经历结构转化，将BAX从非活性构象转化为致死构象，产生线粒体孔。虽然BAX失活突变在肿瘤中的频率很低，但抗凋亡BCL-2成员的显著过表达在癌细胞中更常见，并有助于肿瘤发生和化疗耐药性。因此，绝大多数癌细胞含有功能性但受抑制的BAX。用小分子靶向BAX还没有结束，因为我们对促凋亡BAX激活机制的理解一直是难以捉摸的。最近发现的BAX触发位点和BAX激活剂分子7（其通过与该触发位点结合而触发BAX激活和选择性BAX介导的细胞死亡）使得能够直接和合理地靶向这种高知名度的药物标签。在这里，我们建议评估BAX的触发位点作为重新激活癌细胞死亡的新药理学策略的潜力，并开发BAX激活剂分子（BAM）作为耐药和难治性急性髓性白血病（AML）背景下的潜在治疗候选物。具体来说，我们将基于结构-活性关系的见解和计算机药物设计合成一个新的BAM的集中化学库。将在多种生物物理测定中测试化合物，包括荧光偏振和NMR光谱以及功能性BAX活化测定，其测量化合物通过不同机制触发BAX构象活化、BAX介导的膜parmeabilization和选择性BAX介导的细胞死亡的能力。通过优化效力和选择性的迭代过程，将评价选定的BAM恢复AML细胞中癌细胞死亡的治疗潜力，并将在人AML小鼠模型中评价其药理学特征。因此，我们提出了一种多学科的方法，结合合成化学，结构生物学，生物化学，癌细胞生物学和体内疗效和药代动力学研究，以开发一种新的小分子治疗方法，通过直接靶向BAX恢复癌细胞死亡，并提供BAM用于未来发展成癌症治疗。

DESCRIPTION (provided by applicant): Targeting key apoptosis regulators to overcome the apoptotic resistance of cancer cells is a highly attractive therapeutic strategy. The BCL-2 protein family includes both pro- and anti-apoptotic proteins that form a complex interaction network of checks and balances that regulate the critical balance between cellular life and death. BAX is a pro-apoptotic BCL-2 member that, when activated, undergoes a structural transformation, which converts BAX from an inactive conformation into a lethal one, creating mitochondrial pores. Although inactivating mutations in BAX have been identified with a very small frequency in tumors, significant overexpression of anti-apoptotic BCL-2 members is more common in cancer cells and contributes to tumorigenesis and chemoresistance. Therefore, the vast majority of cancer cells contain functional but suppressed BAX. Targeting BAX with small molecules has not been endeavored, since our understanding of the mechanism of pro-apoptotic BAX activation has been elusive. The recent discovery of the BAX trigger site and BAX activator molecule 7, which triggers BAX activation and selective BAX-mediated cell death through binding to this trigger site, enable the direct and rational targeting of this high-profile drug taget. Here we propose to evaluate the potential of the trigger site of BAX as a novel pharmacological strategy to reactivate cancer cell death and develop BAX activator molecules (BAMs) as potential therapeutic candidates in the context of resistant and refractory Acute Myeloid Leukemia (AML). Specifically, we will synthesize a focused chemical library of novel BAMs based on structure-activity relationship insights and in silico drug design. Compounds will be tested in a variety of biophysical assays, including fluorescence polarization and NMR spectroscopy as well as functional BAX activation assays that measure the capacity of compounds to trigger BAX conformational activation, BAX-mediated membrane parmeabilization and selective BAX-mediated cell death through a distinct mechanism. Through an iterative process of optimizing potency and selectivity, selected BAMs will be evaluated for their therapeutic potential to restore cancer cell death in AML cells and their pharmacological profile will be evaluated in mouse models of human AML. Thus, we propose a multidisciplinary approach that combines synthetic chemistry, structural biology, biochemistry, cancer cell biology and in vivo efficacy and pharmacokinetic studies to develop a novel small-molecule therapeutic approach to restore cancer cell death by directly targeting BAX and providing BAMs for future development into cancer therapeutics.