Optimization of RORgamma-specific agonists as immune activators for a new immunotherapy approach for cancer

 描述（由申请人提供）：本申请是根据标题为“体内化学探针的发现”的PAR-14-279提交的。配体调节的转录因子的核受体（NR）超家族已被证明是靶点的丰富来源， 开发治疗多种人类疾病的药物。NR 1F亚家族被称为视黄酸受体相关孤儿受体或ROR; RORα（NR 1F 1）、RORβ（NR 1F 2）和RORγ（NR 1F 3），调节广泛的生理过程，包括葡萄糖和脂质代谢以及免疫功能。RORα和RORγ在许多组织中广泛表达，包括肝脏、胸腺、肌肉和皮肤，而RORβ具有更有限的表达模式，并且在中枢神经系统（CNS）的区域中发现。虽然它们的生理配体的身份仍然存在争议，但我们是第一个报道甾醇和含氧甾醇作为高亲和力内源性配体的人，其他人已经证实了我们的发现并提供了它们是生理ROR配体的关键证据。T细胞特异性RORγ同种型（RORγt或RORγ2）已被证明是启动TH 17细胞分化程序的关键谱系定义转录因子，使RORγt成为TH 17细胞分化的主要调节因子。 TH 17和Tc 17分化，已证明具有抗肿瘤功效的细胞，以及RORγt控制增强免疫力（包括增加IL 17产生）和减少免疫抑制的基因程序。与这一提议相关的是，我们有令人兴奋的新数据显示，使用RORγt（SR 1078）的合成激动剂激活T细胞可驱动TH 17细胞增殖，并降低免疫检查点蛋白PD-1（程序性细胞死亡蛋白1）的表达，这一机制将增强抗肿瘤免疫力，同时减弱肿瘤相关的适应性免疫抵抗。有趣的是，推定的内源性固醇驱动TH 17细胞的增殖，但不抑制PD-1表达。这表明，RORγt的合成激动剂将激活TC 17/TH 17细胞（减少TcB的数量），抑制PD-1，并原位产生IL 17（IL 17与癌症的良好预后相关）。增强的免疫力和免疫检查点的阻断已经改变了癌症治疗，因此这样的分子将提供与批准的抗PD-1分子的独特组合疗法用于治疗癌症。重要的是，我们的团队是第一个识别ROR合成调节剂的团队。我们开发了泛RORα/RORγt反向激动剂SR 1001和有效的RORγt同种型选择性反向激动剂SR 2211，这是一种抑制TH 17细胞分化和阻断IL 17产生的化合物。对这个提议至关重要的是，我们是第一个发布合成锅的人。 RORα/γt激动剂SR 1078，能够增加HepG 2细胞和SR 1078处理小鼠肝脏中的ROR靶基因。我们的实验室广泛合作开发了泛ROR调节剂、RORα-选择性激动剂和反向激动剂、RORγ t-选择性反向激动剂和RORβ-选择性反向激动剂。因此，我们完全有能力识别、表征和开发有效且选择性的RORγt激动剂。我们的目标是将现有的PAN支架优化为具有良好效力、理化性质和药代动力学的RORγ t选择性激动剂，以提供RORγt激动剂作为探针来询问体内RORγt的活化并确定其在保护性免疫中的作用。

 DESCRIPTION (provided by applicant): This application is being submitted in response to PAR-14-279 titled "Discovery of in vivo Chemical Probes". The nuclear receptor (NR) superfamily of ligand regulated transcription factors has proven to be a rich source of targets for the development of therapeutics for a wide range of human diseases. The NR1F subfamily known as the retinoic acid receptor-related orphan receptors or RORs; RORα(NR1F1), RORβ(NR1F2) and RORγ(NR1F3), regulate a wide range of physiological processes, including glucose and lipid metabolism, and immune functions. RORα and RORγ are widely expressed in many tissues including liver, thymus, muscle, and skin while RORβ has a more restricted expression pattern and is found in regions of the central nervous system (CNS). While the identity of their physiological ligands remains controversial, we were the first to report sterols and oxygenated sterols as high affinity endogenous ligands and others have confirmed our findings and provided key evidence that they are physiological ROR ligands. The T cell specific RORγ isoform (RORγt or RORγ2) has been shown to be the key lineage-defining transcription factor to initiate the differentiation program of TH17 cells making RORγt the master regulator for TH17 and Tc17 differentiation, cells that have demonstrated anti-tumor efficacy, and RORγt controls gene programs that enhance immunity (including increased IL17 production) and decrease immune suppression. Relevant to this proposal, we have exciting new data showing that activation of T cells using a synthetic agonist of RORγt (SR1078) drives proliferation of TH17 cells and decreased expression of the immune checkpoint protein PD-1 (programmed cell death protein 1), a mechanism that will enhance anti-tumor immunity while blunting tumor associated adaptive immune resistance. Interestingly, putative endogenous sterols drive proliferation of TH17 cells but do not repress PD-1 expression. This suggests that synthetic agonists of RORγt will activate TC17/TH17 cells (decreasing the population of Tregs), repress PD-1, and produce IL17 in situ (IL17 is associated with good prognosis in cancer). Enhanced immunity and blockage of immune checkpoints has transformed cancer treatment, thus such a molecule would provide a unique combination therapy with approved anti-PD-1 molecules for treatment of cancer. Importantly, our team was the first to identify synthetic modulators of the RORs. We developed the pan RORα/RORγt inverse agonist SR1001 and the potent RORγt isoform selective inverse agonist SR2211, a compound that suppresses TH17 cell differentiation and blocks IL17 production. Critical to this proposal, we were the first to publish a synthetic pan RORα/γt agonist, SR1078, capable of increasing of ROR target genes in HepG2 cells and in livers from mice treated with SR1078. Our labs have collaborated extensively to develop pan- ROR modulators, RORα-selective agonists and inverse agonists, RORγt-selective inverse agonists, and RORβ-selective inverse agonists. Thus we are well positioned to identify, characterize and develop potent and selective RORγt agonists. Our goal is to optimize current pan scaffolds into RORγt-selective agonists with good potency, physicochemical properties and pharmacokinetics to provide RORγt agonists as probes to interrogate activation of RORγt in vivo and determine its role in protective immunity.