Novel therapeutic target to combat cutaneous lupus

项目概要/摘要：慢性自身炎症性皮肤病，如皮肤红斑狼疮 (CLE)影响到数百万美国人，目前可用的治疗选择有限， 新的治疗选择。CLE的标志是存在针对核酸的自身抗体， 核酸结合蛋白，以及干扰素（IFN）升高。在CLE中，尚不清楚哪些 机制是最关键的沉淀疾病;然而，CLE病变组织学上作为一个界面， 皮炎，这是精心策划的I型和III型干扰素和干扰素调节的趋化因子很大程度上 由下表皮中的基底角质细胞产生。重要的是，我们的一项突破性发现 实验室已经确定了一种抑制I型和III型IFN产生的新型激酶靶点，称为 RIOK3。RIOK 3是RIO蛋白激酶家族（右开放阅读框激酶）的成员，并且是RIO蛋白激酶家族的初步成员。 来自哺乳动物细胞中CRISPR敲除和siRNA敲除的数据表明其在IFN-γ中的突出作用。 生产在敲除研究之后，我们测试了两种能够结合RIOK 3的化合物。它们显著 降低I型和III型干扰素mRNA和蛋白质表达角质形成细胞暴露于多核糖肌苷- 多聚核糖胞苷酸（polyI：C或PIC），一种激活干扰素途径的TLR 3配体。此外，媒体 角质形成细胞中的转移实验证实RIOK 3抑制不仅降低PIC中的IFN应答， 暴露的细胞，但也破坏干扰素前馈回路，如测量干扰素调节蛋白CXCL 10，一个关键 CLE病变中免疫细胞过度募集至皮肤的驱动因素。这项初步工作有力地支持了我们的 中心假设，局部RIOK 3抑制剂将剂量依赖性地减少皮肤IFN和IFN-γ， 调节基因，导致CLE病变减少，与对照组相比， 到系统治疗。重要的是，与JAK抑制剂不同，JAK抑制剂对许多细胞通路具有ON/OFF作用， 局部RIOK 3抑制剂可以选择性地和剂量依赖性地起作用，以精细地调节IFN分泌， 皮肤中的IFN平衡。因此，RIOK 3抑制剂作为新一代的一类药物具有巨大的潜力。 激酶抑制剂。该研究计划有两个主要目标：在SA 1中，我们将完成 一个定义的系列先前确定的，但混杂的，RIOK 3抑制剂对I型和III型IFN， 角质形成细胞这将为基于SAR的选择和最活性化学部分的优化提供信息。这些 化合物将被设计用于局部递送，并将评估RIOK 3活性和选择性。在SA 2中， 我们将确定我们的前三种候选物在刺激的重建人表皮中的功效。顶部 候选人将通过皮肤毒理学研究，并将接受代谢研究，以确保有效的皮肤半- 血液半衰期低。药物化学专家之间合作的总体目标是， 免疫学和皮肤学的目的是证明RIOK 3选择性抑制剂作为第一个 用于治疗患有CLE的成人和儿童患者的同类新型激酶抑制剂。

Project Summary / Abstract: Chronic auto-inflammatory skin diseases such as cutaneous lupus erythematosus (CLE) affect millions of Americans with limited therapeutic options currently available, creating a significant need for novel therapeutic options. A hallmark of CLE is the presence of autoantibodies against nucleic acids and nucleic acid-binding proteins, as well as elevated interferons (IFNs). In CLE it remains unclear which mechanisms are most critical in precipitating disease; however, CLE lesions histologically present as an interface dermatitis, which is orchestrated by type-I and type III interferons and interferon-regulated chemokines largely produced by basal keratinocytes in the lower epidermis. Importantly, a break-through discovery in our laboratories has identified a novel kinase target for the inhibition of type-I and type-III IFN production called RIOK3. RIOK3 is a member of the RIO protein kinase family (right open reading frame kinase) and preliminary data from CRISPR knockout and siRNA knockdowns in mammalian cells demonstrates its prominent role in IFN production. Following knockout studies, we tested two compounds that are able to bind RIOK3. They significantly decreased Type I and III IFN mRNA and protein expression following keratinocyte exposure to polyriboinosinic- polyribocytidylic acid (polyI:C or PIC), a TLR3 ligand that activates interferon pathways. Additionally, media transfer experiments in keratinocytes confirm that RIOK3 inhibition not only reduces the IFN response in PIC exposed cells but also disrupts the IFN feed-forward loop, as measured by IFN-regulated protein CXCL10, a key driver of immune cell hyper-recruitment to the skin in CLE lesions. This preliminary work strongly supports our central hypothesis that a topical RIOK3 inhibitor will dose-dependently decrease cutaneous IFNs and IFN- regulated genes, resulting in the reduction of CLE lesions, with improved efficacy and patient tolerance compared to systemic treatments. Importantly, unlike JAK inhibitors that have an ON/OFF effect on many cellular pathways, a topical RIOK3 inhibitor could work selectively and dose-dependently to finely regulate IFN secretion and restore IFN balance in the skin. Therefore, RIOK3 inhibitors hold immense potential as a novel class of next generation kinase inhibitors. The research proposal has two principal aims: In SA1, we will complete the characterization of a defined series of previously identified, but promiscuous, RIOK3 inhibitors on Type I and Type III IFNs in keratinocytes. This will inform SAR-based selection and optimization of the most active chemical moieties. These compounds will be designed for topical delivery and will be assessed for RIOK3 activity and selectivity. In SA2, we will establish the efficacy of our top three candidates in stimulated reconstructed human epidermis. Top candidates will pass skin toxicological studies and will undergo metabolism studies to ensure effective skin half- life with low blood half-life. The overall goal of this collaborative effort between experts in medicinal chemistry, immunology, and dermatology is to demonstrate the incredible potential of RIOK3 selective inhibitors as a first- in-class, novel kinase inhibitor for treatment of adult and pediatric patients suffering from CLE.