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

 描述(申请人提供)：本申请是根据PAR-14-279题为“体内化学探针的发现”而提交的。核受体(NR)超家族的配体调节转录因子已被证明是一个丰富的靶点来源 治疗人类多种疾病的疗法的发展。NR1F亚家族被称为视黄酸受体相关的孤儿受体或RORs；RORα(NR1F1)、RoRβ(NR1F2)和RoRγ(NR1F3)调节广泛的生理过程，包括糖和脂代谢，以及免疫功能。RoRα和RoRγ广泛表达于肝脏、胸腺、肌肉和皮肤等多种组织中，而RoRβ的表达模式较为有限，主要分布于中枢神经系统。虽然它们的生理配体的身份仍然存在争议，但我们首次报道了甾醇和含氧甾醇是高亲和力的内源性配体，其他人已经证实了我们的发现，并提供了关键证据，表明它们是生理ROR配体。T细胞特异性的rorγ亚型(rorγt或rorγ2)被证明是启动th17细胞分化程序的关键转录因子，使rorγt成为 Th17和Tc17的分化，已经显示出抗肿瘤效果的细胞，以及rorγt，控制增强免疫的基因程序(包括增加IL17的产生)和减少免疫抑制。与这一建议相关的是，我们有令人兴奋的新数据表明，使用合成的RoRγt激动剂(SR1078)激活T细胞可以促进TH17细胞的增殖，并减少免疫检查点蛋白PD-1(程序化细胞死亡蛋白1)的表达，这一机制将增强抗肿瘤免疫，同时钝化肿瘤相关的适应性免疫抵抗。有趣的是，推测的内源性类固醇促进了TH17细胞的增殖，但并不抑制PD-1的表达。这表明合成的RoRγt激动剂将激活Tc17/Th17细胞(减少Tregs的数量)，抑制PD-1，并原位产生IL17(IL17与癌症的良好预后有关)。增强的免疫力和免疫检查点的阻断改变了癌症的治疗，因此这种分子将提供一种独特的与已批准的抗PD-1分子联合治疗癌症的方法。重要的是，我们的团队是第一个确定RoR的合成调节器的人。我们开发了PAN RoRα/RoRγt反向激动剂SR10 0 1和有效的RoRγt异构体选择性反向激动剂SR2 2 11，这是一种抑制TH17细胞分化和阻断IL 17产生的化合物。对这项提议至关重要的是，我们是第一个发布合成PAN的人 Rorα/γt激动剂sr1078能增加人肝癌细胞和sr1078处理小鼠肝脏中的ror靶基因表达。我们的实验室广泛合作开发泛RoR调节剂、RoRα选择性激动剂和反向激动剂、RoRγt选择性反向激动剂和RoRβ选择性反向激动剂。因此，我们处于有利地位，可以识别、表征和开发有效和选择性的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、物理化学性质和药代动力学的RoRγt选择性激动剂，以提供RoRγt激动剂作为探针来询问RoRγt在体内的激活情况，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.