Role of genomic and microenvironment factors in conferring acquired resistance to ferroptosis to chemoradiation in esophageal adenocarcinoma

项目3摘要 食管癌是世界范围内第六大常见死因，5年生存率低于 百分之二十与其他胸内恶性肿瘤（如肺癌）相似，放化疗（CRT）是一种有效的治疗方法。 治疗食管腺癌（EAC）的有效工具。然而，CRT导致完全反应， EAC仅约25%的患者。因此，表征发生的细胞和分子变化 在CRT期间肿瘤和肿瘤微环境中的变化可以提供高度准确的预测工具， 哪些EAC患者会对治疗产生获得性耐药性。CRT诱导细胞死亡途径铁凋亡 在癌细胞中，并且假设铁凋亡是获得性放射治疗抗性的关键调节剂， 获得性抗铁治疗（阿尔蒂）中心的中心主题。项目3将有助于 通过在项目1中发现的临床前模型中桥接基础科学机制， 项目2，临床EAC肿瘤活检，在基线（治疗前）和治疗中期收集 CRT方案。这些EAC肿瘤活检将进行单细胞转录组分析，以确定表达 并提供了一个复杂的通信之间的理解肿瘤 细胞和细胞的肿瘤微环境，可以驱动和/或调节铁凋亡（目的1）。识别 直接或间接与铁凋亡相关的转录组可能有助于诊断EAC患者， 可能对CRT有反应，也可能没有反应。进一步的空间细胞映射和破译差异表达的细胞之间的关系。 与铁凋亡相关的表达基因将为肿瘤在发生铁凋亡时逃避铁凋亡的能力提供证据。 辐照目标2将集中于确定对治疗的适应性抵抗是否由于选择 罕见，但预先存在的肿瘤细胞，或由于直接或间接相关基因的从头获得改变 铁凋亡信号通路。目标3将致力于阐明肿瘤微环境机制， 可能会赋予CRT对铁细胞下垂的抵抗力，例如成纤维细胞，已被证明可以调节胱氨酸 转运蛋白SCL 7A 11促进铁凋亡抗性。此外，肿瘤浸润的免疫细胞与 将分析缺氧特征与对CRT的铁凋亡抗性的关联。在EAC肿瘤中 对CRT耐药，观察到髓系细胞扩增，并观察到髓系细胞的表型和活化状态。 将使用原位移植的患者来源的EAC肿瘤进行评估。A的进一步应用 来自阿尔蒂中心分子成像核心的创新正电子发射断层扫描示踪剂， 在耐药肿瘤中观察到的与髓系细胞扩增相关的肿瘤的氧化电位将有助于 发现与铁凋亡相关的分子和细胞途径。项目3将反复加强和支持 基础科学/机械学项目1和2以及项目3将对阿尔蒂中心的目标做出重大贡献 来识别那些最有可能产生获得性辐射抗性的病人。

Project 3 Summary Esophageal cancer is the sixth most common cause of deaths worldwide with a 5-year survival rate of less than 20%. Similar to other intrathoracic malignancies, such as lung cancer, chemoradiation therapy (CRT) is an effective tool for treating esophageal adenocarcinoma (EAC). However, CRT leads to complete responses in EAC in only approximately 25% of patients. Thus, characterizing the cellular and molecular changes that occur in the tumor and tumor microenvironment during CRT can provide highly accurate predictive tools to identify which EAC patients will develop acquired resistance to therapy. CRT induces the cell death pathway ferroptosis in cancer cells, and the hypothesis that ferroptosis is a key regulator in acquired radiation therapy resistance is a central theme of the Acquired Resistance to Therapy and Iron (ARTI) Center. Project 3 will contribute to this central theme by bridging the basic science mechanisms in preclinical models discovered in Project 1 and Project 2 with clinical EAC tumor biopsies, collected at baseline (before treatment) and during the middle of the CRT regimen. These EAC tumor biopsies will undergo single cell transcriptome profiling to identify expression of ferroptosis-related genes and to provide an understanding of the complex communications between tumor cells and cells of the tumor microenvironment that may drive and/or regulate ferroptosis (Aim 1). Identification of transcriptomes that are directly or indirectly related to ferroptosis may help to prognose EAC patients who may or may not respond to CRT. Further spatial cellular mapping and deciphering the relationship of differentially expressed genes with ferroptosis will provide evidence for the tumor’s ability to evade ferroptosis upon irradiation. Aim 2 will focus on determining whether adaptive resistance to therapy occurs due to selection of rare, but pre-existing tumor cells, or due to de novo acquisition of alterations in genes directly or indirectly related to ferroptosis signaling pathways. Aim 3 will focus on elucidating the tumor microenvironment mechanisms that may confer ferroptosis resistance to CRT, such as fibroblasts, which have been shown to regulate the cystine transporter SCL7A11 that promotes ferroptosis resistance. In addition, tumor-infiltrated immune cells with hypoxic signatures will be analyzed for their association with ferroptosis resistance to CRT. In EAC tumors resistant to CRT, myeloid cell expansion was observed, and the phenotype and activation status of myeloid cells will be assessed using orthotopically transplanted patient derived EAC tumors. Further application of an innovative positron emission tomography tracer from the Molecular Imaging Core of the ARTI Center to assess oxidative potential of tumors as related to the myeloid cell expansion observed in resistant tumors will help discover molecular and cellular pathways related to ferroptosis. Project 3 will iteratively strengthen and support the basic science/mechanistic Projects 1 and 2, and Project 3 will significantly contribute to the ARTI Center goal of identifying patients who are at greatest risk to develop acquired radiation resistance.