ULK1 Inhibitor in Combination with Immune Checkpoint Blockade in PancreaticCancer

项目总结 胰腺癌是美国第三大与癌症相关的死亡原因，另外6万人死于胰腺癌。 美国人将在2022年被确诊。此外，胰腺导管腺癌(PDAC)的患者面临着 5年生存率低于5%。尽管PDAC的遗传驱动因素已经被很好地确定，但这些 癌症在很大程度上仍然难以治疗。为了生存，PDAC依赖自噬，这是一种细胞内的营养物质 回收过程。自噬为肿瘤细胞存活提供了内部营养库，而胰腺星状 细胞也使用自噬来支持他们的新陈代谢需求。此外，自噬有助于免疫逃避， PDAC的一个众所周知的治疗挑战。与这些作用一致的是，基因自噬抑制 显示可以减少PDAC肿瘤的生长；然而，这些发现的翻译受到缺乏 可用于临床前使用的药理自噬抑制剂。 为了解决这个问题，我们的实验室开发了一种有效的、选择性的ULK1小分子抑制剂(ULK-101)， 一种控制自噬诱导的蛋白激酶。重要的是，我们已经证明饥饿的癌细胞 对ULK1抑制高度敏感，与应激期间依赖自噬的存活一致。虽然有几个 ULK1抑制剂的存在，我们已经证明了ULK-101是迄今为止最有效和最有选择性的，也是理想的 临床前研究的候选人。因此，我们建议评估ULK-101在小鼠体内的作用 胰腺癌模型。我们推测ULK-101通过抑制ULK1抑制自噬 从而减少胰腺肿瘤的生长，提高治疗效果。 Aim 1将使用人胰腺癌细胞系(MIA PACA-2和PANC-1)建立原位肿瘤模型 为了测试ULK-101治疗是否可以减少体内肿瘤的进展。然后我们将使用这些正位模型 通过使用化学蛋白质组学测量ULK1抑制来评估靶点结合和ULK-101的选择性。 这些原位模型也将用于评估ULK-101对肿瘤进展的影响，我们将 对照羟氯喹，一种批准的溶酶体抑制剂。对于目标2，我们将使用同基因 7940b小鼠原位肿瘤模型和已建立的胰腺KPC小鼠(LSL-KrasG12D/+， LSL-Trp53R172H/+，Pdx1-cre模型)，以检测ULK-101是否会降低肿瘤负担。因为自噬 抑制使PDAC对免疫治疗敏感，我们还将评估ULK-101与双重免疫的结合 检查站封锁(抗CTL4和抗PD-1)。Aim 2中的转基因小鼠模型具有一种 功能免疫系统，适当部位的肿瘤，以及与人类相似的疾病进展 胰腺癌。 通过这些深入的体内研究，我们将检验ULK1抑制作为治疗胰腺的策略 并可能为ULK-101和新型自噬抑制剂的进一步开发提供证据。

PROJECT SUMMARY Pancreatic cancer is responsible for the third most cancer-related deaths in the United States, and >60,000 Americans will be diagnosed in 2022. Further, patients with pancreatic ductal adenocarcinoma (PDAC) face a 5-year survival rate of less than 5%. Although the genetic drivers of PDAC have been well established, these cancers remain largely refractory to treatment. To survive, PDACs depend on autophagy, an intracellular nutrient recycling process. Autophagy provides an internal nutrient pool for tumor cell survival, and pancreatic stellate cells also use autophagy to support their metabolic demands. Further, autophagy contributes to immune evasion, a well-known therapeutic challenge in PDAC. Consistent with these roles, genetic autophagy inhibition has been shown to reduce PDAC tumor growth; however, the translation of these discoveries is limited by a lack of pharmacologic autophagy inhibitors available for preclinical use. To address this problem, our lab developed a potent and selective small molecule inhibitor of ULK1 (ULK-101), a protein kinase that controls autophagy induction. Importantly, we have shown that starved cancer cells are highly sensitive to ULK1 inhibition, consistent with autophagy-dependent survival during stress. While several ULK1 inhibitors exist, we have demonstrated that ULK-101 is the most potent and selective to date and the ideal candidate for preclinical investigations. Therefore, we propose to evaluate the effects of ULK-101 in mouse models of pancreatic cancer. We hypothesize that ULK-101 will suppress autophagy through ULK1 inhibition and thereby reduce pancreatic tumor growth and improve therapeutic efficacy. Aim 1 will use an orthotopic tumor model using human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1) to test whether ULK-101 treatment reduces tumor progression in vivo. We will then use these orthotopic models to assess target engagement and ULK-101 selectivity by measuring ULK1 inhibition using chemoproteomics. These orthotopic models will also be used to evaluate the effect of ULK-101 on tumor progression, which we will benchmark against hydroxychloroquine, an approved lysosomal inhibitor. For Aim 2, we will use a syngeneic orthotopic tumor model with 7940b murine cells and the established pancreatic KPC mouse (LSL-KrasG12D/+, LSL-Trp53R172H/+, Pdx1-cre model) to test whether ULK-101 will decrease tumor burden. Because autophagy inhibition sensitizes PDACs to immunotherapy, we will also evaluate ULK-101 in combination with dual immune checkpoint blockade (anti-CTL4 and anti-PD-1). The genetically engineered mouse model in Aim 2 features a functional immune system, tumors at the appropriate site, and disease progression that parallels human pancreatic cancer. Through these thorough in vivo studies, we will examine ULK1 inhibition as a strategy for treating pancreatic cancer and may provide evidence for further development of ULK-101 and novel autophagy inhibitors.