ALDH Inhibition as Modulator of Tumor Immunobiology

卵巢癌是一种致命性疾病，在女性癌症死亡中排名第五，死亡率居第三位。 与所有癌症的发病率之比。由于几十年来患者的总体存活率没有显著变化， 为卵巢癌开发新的治疗方法是一个明显的未得到满足的临床需求。乙醛脱氢酶-1A酶 (ALDH1A)代表了OvCa的治疗靶点。ALDH1A酶在卵巢癌中表达上调 启动细胞(CIC)并介导维甲酸(RA)的生物合成，以调节众多细胞 流程。我们最近发现了一种新的ALDH1a家族抑制剂(ALDHi)。我们的初步数据显示 ALDHi治疗癌细胞和免疫细胞有相反的作用，两者都可以促进抗 肿瘤免疫。ALDHi治疗CIC诱导RA和转录依赖的坏死性细胞死亡 可能与RA转录伙伴NR4A1的功能改变有关。ALDHi诱导的CIC死亡是 与损伤相关分子模式(DAMP)和其他炎症的释放相关 调解人。相反，ALDHi治疗与两种树突状细胞的增殖反应增强相关 (DC)和CD8+T细胞。我们的主要假设是ALDHi可以作为一种免疫调节剂 可用于加强卵巢癌的免疫治疗方法。为了检验我们的假设，我们提出了 以下特定目标：SA1：确定RA受体和驱动ALDHi诱导的CIC的下游因素 并确定ALDHi诱导的CIC坏死性下垂是否为炎性细胞死亡。我们建议 检测单个RA受体RAR/RXR和NR4A1共受体在ALDHi介导的CIC死亡和死亡中的作用 评估ALDHi/NR4A1对炎性介质CIC释放的影响以及这种刺激对抗炎性介质的作用 肿瘤T细胞反应。接下来，我们将在SA2中：评估ALDHi对主机DC和T的影响 细胞。由于RA可以调节T细胞和DC的分化，我们将使用报告小鼠来评估其作用 ALDHi在体内外对RA/NR4A1信号转导及DC和T细胞生物学的影响。我们将评估 树突状细胞分化为产生IL-12的Dc1和CD4T辅助细胞亚群分化的能力 重点研究Th17/Treg的反式分化。最后，我们的初步数据表明，ALDHi可能会增强抗- 通过对肿瘤细胞和免疫细胞的作用而产生的肿瘤免疫。因此，我们建议SA3：确定 ALDHi在卵巢癌免疫治疗中的作用为了验证这一假设，我们将使用几种免疫 OvCa的胜任模型确定ALDHi增强检查点抑制物治疗的能力 抗肿瘤疫苗。 影响：虽然免疫疗法在许多癌症中显示出显著的好处，但对卵巢癌的影响 是有限的。这里提出的研究将确定一种新的治疗性ALDHi在免疫治疗中的作用 卵子。鉴于ALDH与癌症的治疗耐药性广泛相关，这些研究将具有深远的意义 对癌症治疗的启示。

Ovarian cancer (OvCa) is a deadly disease ranking 5th in cancer deaths in women, with the 3rd highest mortality to incidence ratio of all cancers. With patient overall survival not significantly changed for several decades, there is a clear unmet clinical need to develop new therapies for OvCa. Aldehyde dehydrogenase-1A enzymes (ALDH1A) represent a therapeutic target for OvCa. ALDH1A enzymes are upregulated in ovarian cancer initiating cells (CIC) and mediate the biosynthesis of retinoic acid (RA), to regulate numerous cellular processes. We recently identified a novel ALDH1A family inhibitor (ALDHi). Our preliminary data indicate that ALDHi treatment of cancer cells and immune cells have opposite effects, both of which could promote anti- tumor immunity. ALDHi treatment of CIC induces an RA and transcription- dependent necroptotic cell death, potentially related to altered function of the RA transcription partner NR4A1. This ALDHi-induced CIC death is associated with the release of Damage Associated Molecular Patterns (DAMPs) and other inflammatory mediators. In contrast, ALDHi treatment is associated with enhanced proliferative response of both dendritic cells (DC) and CD8+ T cells. Our overarching hypothesis is that ALDHi can act as an immune modulator and can be used to enhance immunotherapeutic approaches in OvCa. To test our hypotheses, we propose the following specific aims: SA1: To identify the RA receptors and downstream factors that drive ALDHi induced CIC necrosis and to determine whether ALDHi-induced CIC necroptosis is inflammatory cell death. We propose to test the role of individual RA receptors RAR/RXR and NR4A1 co-receptor in ALDHi-mediated CIC death and evaluate the impact of ALDHi/NR4A1 on CIC release of inflammatory mediators and this stimulation of an anti- tumor T cell response. Next, we will, in SA2: Assess the impact of ALDHi on host DC and T cells. As RA can regulate the differentiation of T cells and DC, we will use reporter mice to evaluate the role of ALDHi on disruption of RA/NR4A1 signaling and DC and T cell biology in vitro and in vivo. We will evaluate the capacity of DC to differentiate into IL-12 producing DC1, and CD4 T helper cell subsets differentiation with focus on the Th17/Treg trans-differentiation. Finally, our preliminary data suggest ALDHi may enhance anti- tumor immunity both via actions on the tumor cell and immune cells. We therefore propose SA3: To determine the ability of ALDHi to enhance immunotherapy in OvCa. To test this hypothesis, we will use several immune competent models of OvCa to determine the ability of ALDHi to enhance checkpoint inhibitor therapy and antitumor vaccines. IMPACT: While immune therapy has demonstrated significant benefit in many cancers, the impact in OvCa has been limited. The studies proposed here will define the role for a novel therapeutic ALDHi in immunotherapy in OvCa. Given ALDH is broadly linked with therapeutic resistance in cancer, these studies will have far-reaching implications for cancer therapy.