Structure-Function Investigation of Chemokine-GPCR Signaling in Tumor Progression and Metastasis

项目摘要 卵巢上皮癌（EOC）是女性癌症死亡的第五大原因。平等机会委员会有90% 如果早期发现，存活率很高，但由于其非特异性症状，许多病例未被发现， 转移已经存在。在其晚期转移阶段，没有有效的治疗方法可用于 平等机会委员会此外，EOC复发是常见的，并且经常与对肿瘤的敏感性丧失有关。 可用的疗法。因此，迫切需要新的EOC治疗剂，特别是靶向治疗EOC的那些治疗剂。 转移肿瘤细胞迁移到新部位的一种方式是通过趋化因子。趋化因子很小 在疾病和稳态过程中指导细胞迁移或趋化性的分泌蛋白。 趋化因子通过与它们的同源细胞表面受体结合来触发细胞迁移，这些受体是趋化因子家族的成员。 G蛋白偶联受体超家族。趋化因子与其受体的结合触发信号传导 级联，最终在细胞骨架重组和趋化性高趋化因子浓度的地区。 肿瘤细胞可以通过上调趋化因子和趋化因子受体表达来劫持这一过程， 肿瘤细胞沿着趋化因子梯度迁移到远处。趋化因子受体XCR 1具有 在许多癌症中表达增加，并与肿瘤细胞增殖增加有关， 迁移在鼠模型中，XCR 1的沉默已显示出显著降低EOC的转移。 我们的实验室最近对XCL 1（XCR 1的趋化因子配体）进行了深入的表征，导致了 识别对受体结合和活化至关重要的配体残基。这项建议旨在 通过阐明XCR 1中的重要残基来推进这一知识，XCR 1是比其更可行的药物靶点。 XCL 1-XCR 1轴在上皮性卵巢癌转移中的作用。 具体来说，该奖学金的目标是使用互补的生化和功能方法， 检验XCL 1-XCR 1界面的特定分子间接触是EOC的关键驱动因素的假设 细胞迁移研究金研究将包括两个具体目标。目标1将检验以下假设： XCR 1的正构结合口袋中的某些残基对于XCR 1-XCL 1信号传导至关重要。目标2将测试 假设XCR 1由先前未探测XCR 1表达的人EOC细胞系表达，和 变体XCL 1蛋白将在XCR 1阳性人类EOC细胞中引发独特的趋化特征，包括 这些发现在第一部分的目的。这项研究将在位于纽约的布莱恩·沃特曼实验室进行。 威斯康星州医学院，一个高度协作和刺激的环境，配备了 基础设施和设备，使这项建议取得成功。总而言之，了解基本的结构 趋化因子配体-受体相互作用的特征将揭示驱动肿瘤进展的机制， 转移利用结构和功能的互补关系将产生重要的洞察力， 开发更好和更特异的治疗方法，靶向癌症进展和转移。

PROJECT SUMMARY Epithelial Ovarian Cancer (EOC) is the 5th leading cause of cancer death in women. EOC has a 90% survival rate if detected early, but due to its non-specific symptoms, many cases go undetected until metastases are already present. In its late metastatic stages, there are no effective treatments available for EOC. Furthermore, EOC recurrence is common, and is frequently associated with loss of sensitivity to available therapies. Thus, there is a dire need for novel EOC therapeutics, especially those that target metastasis. One way that tumor cells can migrate to new sites is via chemokines. Chemokines are small secreted proteins that direct the cell migration, or chemotaxis, in both disease and homeostatic processes. Chemokines trigger cell migration by binding to their cognate cell-surface receptors, which are members of the G-Protein Coupled Receptor superfamily. Binding of chemokines to their receptors triggers a signaling cascade, culminating in cytoskeletal reorganization and chemotaxis to areas of high chemokine concentration. Tumor cells can hijack this process by upregulating chemokine and chemokine receptor expression, allowing tumor cells to migrate to distant sites along chemokine gradients. The chemokine receptor XCR1 has increased expression in many cancers and has been associated with increased tumor cell proliferation and migration. Silencing of XCR1 in murine models has been shown to significantly decrease metastasis of EOC. Our lab recently performed in-depth characterization of XCL1, the chemokine ligand for XCR1, leading to the identification of ligand residues that are critical for receptor binding and activation. This proposal aims to advance this knowledge by elucidating important residues in XCR1, which is a more viable drug target than its ligand, and to study the functional role of the XCL1-XCR1 axis in the metastasis of epithelial ovarian cancer. Specifically, the goal of this fellowship is use complementary biochemical and functional approaches to test the hypothesis that specific intermolecular contacts at the XCL1-XCR1 interface are critical drivers of EOC cell migration. The fellowship research will consist of two specific aims. Aim 1 will test the hypothesis that certain residues in XCR1's orthosteric binding pocket are crucial for XCR1-XCL1 signaling. Aim 2 will test the hypothesis that XCR1 is expressed by human EOC cell lines not previously probed for XCR1 expression, and that variant XCL1 proteins will elicit unique chemotactic profiles in XCR1-positive human EOC cells including those discovered in the first part of this aim. The research will take place in the Brian Volkman lab at the Medical College of Wisconsin, a highly collaborative and stimulating environment that is well equipped with the infrastructure and equipment to make this proposal a success. In all, understanding the fundamental structural characteristics of chemokine ligand-receptor interactions will reveal mechanisms driving tumor progression and metastasis. Exploiting the complementary relationship of structure and function will yield vital insight towards the development of better and more specific therapeutics targeting cancer progression and metastasis.