Androgen Activation of Innate Immune Signaling to Enhance Prostate Cancer Immune Response

双极雄激素治疗（BAT）是治疗去势抵抗性前列腺癌的一种矛盾方法 （CRPC），其中睾酮水平在超生理和去势浓度之间快速循环。 了解BAT如何在分子和细胞水平上发挥作用，可能有助于将BAT与 其他药剂以实现增加的功效和肿瘤反应。先前的观察表明， 超生理睾酮（SupraT）诱导DNA双链断裂（DSB）。据推测，如果 如果不修复，DSB可能导致细胞危象和细胞凋亡。在这项提案中，我们提供了新的证据， 由SupraTs诱导的未修复的DSB被路由到自噬体，在那里它们激活细胞质核酸， 酸传感器，触发下游干扰素刺激基因（ISG）和先天免疫途径。基于 根据我们的初步数据，我们提出了一个新的想法，即：i）由SupraTs引起的未修复的DSB被路由为 专门的自噬降解称为噬核; ii）SupraTs诱导的自噬体DNA可以激活 细胞质DNA传感途径-特别是核酸传感途径（cGAS-STING和RIG-I iii）SupraTs对核酸传感途径的激活在前列腺肿瘤中更明显 具有DNA修复缺陷; iv）BAT可能特别激活先天性和适应性免疫细胞， 有DNA修复缺陷的患者。在这个提议中，我们将确定核酸传感器在介导 免疫信号传导由SupraTs在PCa。利用接受BAT的PCa患者的肿瘤活检，我们将评估 核酸传感器介导的先天免疫信号传导是否作为治疗的分子决定因素 反应为了验证我们的假设，我们将利用几种创新工具和资源，包括CRISPR-Cas9 生成的敲除细胞模型，肿瘤中免疫景观的GeoMx数字空间分析 微环境，独特的患者来源的前列腺癌异种移植物模型，人源化小鼠模型， 功能性先天和适应性免疫细胞，以及来自接受BAT的患者的血清和肿瘤活检。我们认为 这些独特的资源使我们有能力进行建议的工作，并立即产生临床效果。我们有 组建了一个基础和临床前列腺癌生物学和免疫治疗专家团队， 独特的专业知识来成功实现我们的目标。成功完成拟议工作将产生： a）对SupraTs调节免疫应答的机制见解，B）对激活的有价值的临床见解 c）新的基于肿瘤和血清的标志物，其可用于开发 预测治疗反应的生物标志物，以及d）提供战略性地利用BAT来激活 免疫反应，并将其与增强适应性免疫系统的免疫治疗剂相结合， 免疫检查点阻断和T细胞治疗以实现协同作用。

Bipolar androgen therapy (BAT) is a paradoxical approach for the treatment of castration-resistant prostate cancer (CRPC) whereby testosterone levels are rapidly cycled between supraphysiologic and castrate concentrations. Understanding how BAT works at the molecular and cellular levels might help in rationally combining BAT with other agents to achieve increased efficacy and tumor responses. Previous observations suggest that supraphysiological testosterone (SupraT) induce DNA double strand breaks (DSB). It has been speculated that if left unrepaired, DSBs may lead to cellular crisis and apoptosis. In this proposal, we provide novel evidence that unrepaired DSBs induced by SupraTs are routed to the autophagosomes where they activate cytoplasmic nucleic acid sensors that trigger the downstream interferon stimulated genes (ISGs) and innate immune pathways. Based on our preliminary data, we propose a novel idea that: i) Unrepaired DSBs induced by SupraTs are routed for specialized autophagic degradation termed nucleophagy; ii) SupraTs induced autophagosomal DNA can activate cytoplasmic DNA sensing pathways~ specifically the nucleic acid sensing pathway (cGAS-STING and RIG-I pathway); iii) Activation of nucleic acid sensing pathway by SupraTs would be more pronounced in prostate tumors that have DNA repair defect; and iv) BAT might activate innate and adaptive immune cells specially, in a subset of patients having DNA repair defect. In this proposal, we will determine the role of nucleic acid sensors in mediating immune signaling by SupraTs in PCa. Utilizing tumor biopsies from PCa patients receiving BAT, we will evaluate whether nucleic acid sensor mediated innate immune signaling serves as a molecular determinant of treatment response. To test our hypothesis, we will utilize several innovative tools and resources including CRISPR-Cas9 generated knockout cellular models, GeoMx Digital Spatial profiling of immune landscape in the tumor microenvironment, unique patient derived prostate cancer xenografts models, a humanized mouse models that has functional innate and adaptive immune cells, and serum and tumor biopsies from patients receiving BAT. We think these unique resources position us well to undertake the proposed work with immediate clinical impact. We have assembled a team of experts in basic and clinical prostate cancer biology and immunotherapy who will provide their unique expertise to successfully accomplish our goals. Successful completion of the proposed work will generate: a) mechanistic insights into modulation of immune response by SupraTs, b) valuable clinical insights into activation of immune cells by BAT, c) novel tumor- and serum-based markers that can be utilized for the development of biomarkers predictive of therapy response, and d) provide a rationale for strategically utilizing BAT to activate immune response and combine it with immunotherapeutics that empower the adaptive immune system such as immune checkpoint blockade and T-cell therapeutics to achieve synergy.