Targeting epigenetic reader GAS41

摘要 组蛋白的翻译后修饰在染色质转录调控中起着重要的作用 在人类癌症中。组蛋白乙酰化与活跃的基因转录相关，并在基因转录中起着至关重要的作用。 肿瘤发生事实上，靶向参与调节组蛋白修饰的蛋白质的小分子是非常有用的。 作为一种非常有前途的抗癌药物正在探索中，目前有许多化合物正在进行临床试验 (e.g. BRD 4抑制剂）。近年来，YEATS结构域被发现是一种新型的乙酰组蛋白阅读器 域.最初发现GAS 41在23%的胶质母细胞瘤和80%的星形细胞瘤中扩增。新兴 研究强烈暗示GAS 41是非小细胞肺癌（NSCLC）中的癌基因。GAS 41是 在NSCLC中经常扩增，GAS 41敲低或与乙酰化 组蛋白抑制肺癌细胞生长。 我们最近发现GAS 41是双乙酰化H3组蛋白的阅读器。全长GAS 41是二聚体， 细胞并以高亲和力结合二乙酰化的H3。基于这一发现，我们开发了一套生化 适用于表征GAS 41蛋白-蛋白相互作用和鉴定小分子的测定 抑制剂的在这项提案中，我们计划使用高通量开发GAS 41的小分子抑制剂 在密歇根大学的CCG中进行HTS筛查。将验证GAS 41的小分子抑制剂 并在一系列生物化学和生物物理实验中表征。最有效的活性 化合物将在基于细胞的测定中表征，以评估GAS 41与 染色质和了解作用机制。选定的GAS 41抑制剂也将在一组 肺癌细胞系。总之，我们期望鉴定出高度有价值的化学探针化合物， GAS 41蛋白质-蛋白质相互作用适合于机制研究，并为开发 有效的体内活性GAS 41抑制剂。

Abstract Post-translational modifications on histone proteins play an essential role in regulating chromatin transcription in human cancers. Histone acetylation is associated with active gene transcription and plays a crucial role in tumorigenesis. Indeed, small molecules targeting proteins involved in regulation of histone modifications are being explored as a very promising anti-cancer agents, with a number of compounds currently in clinical trials (e.g. BRD4 inhibitors). Recently, the YEATS domains have been discovered as novel acetyl-histone reader domains. GAS41 was originally found to be amplified in 23% glioblastomas and 80% astrocytoma. Emerging studies strongly implicate GAS41 as an oncogene in Non-Small Cell Lung Cancer (NSCLC). GAS41 is frequently amplified in NSCLC and knockdown of GAS41 or disruption of the interaction with acetylated histones suppresses lung cancer cell growth. We have recently found that GAS41 is a reader of di-acetylated H3 histone. Full-length GAS41 is dimeric in cells and binds di-acetylated H3 with high affinity. Based on this finding we developed suites of biochemical assays suitable for characterization of GAS41 protein-protein interactions and identification of small molecule inhibitors. In this proposal we plan to develop small molecule inhibitors of GAS41 using high throughput screening (HTS) in CCG at the University of Michigan. Small molecule inhibitors of GAS41 will be validated and characterized in a series of biochemical and biophysical experiments. Activity of the most potent compounds will be characterized in cell-based assays to assess the disruption of GAS41 interactions with chromatin and understand mechanism of action. Selected GAS41 inhibitors will be also profiled in a panel of lung cancer cell lines. In summary, we expect to identify highly valuable chemical probe compounds targeting GAS41 protein-protein interactions suitable for mechanistic studies and pave the way towards development of potent in vivo active GAS41 inhibitors.