Role of hypoxia in fibroblast reprogramming in pancreatic cancer

缺氧在胰腺癌成纤维细胞重编程中的作用

• 批准号: 10748608
• 负责人: Tenzin Ngodup
• 金额: $ 4.08万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10748608
• 关键词: 3-Dimensional; Accounting; Area; Blood Vessels; Cancer Control; Cells; Coculture Techniques; Data; Desmoplastic; Diagnosis; Disease; Extracellular Matrix; Fibroblasts; Goals; Human; Hypoxia; Hypoxia Inducible Factor; Immune; Incidence; Inflammatory; Interleukin-1; Knock-out; Link; M cell; Malignant Neoplasms; Malignant neoplasm of pancreas; Mediating; Mediator; Molecular; Mus; Mutation; Oxygen; Pancreatic Ductal Adenocarcinoma; Pathway interactions; Patients; Play; Production; Proteins; Regulation; Resistance; Role; Sampling; Signal Pathway; Signal Transduction; Stromal Cells; System; Testing; Therapeutic; Tissues; Wit; Work; cancer cell; cancer therapy; cytokine; density; design; genetic signature; hypoxia inducible factor 1; in vivo; insight; mortality; mouse model; neoplastic cell; normoxia; novel therapeutic intervention; pancreatic cancer cells; pancreatic tumorigenesis; response; single-cell RNA sequencing; therapy resistant; tumor; tumor hypoxia; tumor initiation; tumor microenvironment; tumorigenesis

PROJECT SUMMARY Pancreatic ductal adenocarcinoma (PDAC) is a prevalent form of pancreatic cancer, accounting for about 90% of all cases of this disease. PDAC is highly fatal, where mortality closely parallels incidence, primarily due to the inability to diagnose PDAC at early stages and resistance to all existing treatments. Besides genetic changes in tumor cells, the tumor microenvironment plays a key role in tumor initiation, progression, and therapeutic resistance. PDAC is notable for its dense desmoplastic stroma, consisting of extracellular matrix, cancer- associated fibroblasts (CAFs), and immune cells. Another notable feature of the PDAC microenvironment is hypoxia, a condition of insufficient oxygen availability. Although hypoxia leads to adaptive responses in both cancer cells and stromal cells, the effects of hypoxia and hypoxia-inducible factor 1ɑ (HIF1ɑ), a master regulator of hypoxic adaptation, on the PDAC stroma and tumor-stroma interactions are not fully understood. We have recently found that inflammatory CAFs (iCAFs), a CAF subset producing high levels of inflammatory cytokines, are linked to the hypoxia-related gene signature and the HIF1 signaling pathway in human and mouse PDAC. By exposing 3D cocultures of pancreatic tumor cells and fibroblasts to either hypoxia or normoxia, we demonstrated that hypoxia promotes iCAF formation via IL1ɑ secreted from tumor cells. Importantly, the presence of hypoxic fibroblasts further elevated IL1ɑ levels in tumor cells, implicating hypoxia as a modulator of bidirectional interactions between tumor cells and fibroblasts. Based on these data, I hypothesize that hypoxia promotes iCAF formation by modulating bidirectional interactions between tumor cells and fibroblasts in PDAC. In Specific Aim 1, I will determine how hypoxia induces IL1ɑ expression in tumor cells via fibroblasts by using a three-dimensional (3D) coculture system of pancreatic tumor cells and fibroblasts and exposing the coculture to either hypoxia or normoxia. In Specific Aim 2, I will determine whether and how fibroblast HIF1ɑ regulates tumor cell-fibroblast interactions and pancreatic tumorigenesis by using 3D cocultures of tumor cells and fibroblasts deficient of HIF1ɑ, and using mouse models lacking fibroblast expression of HIF1ɑ. My work will identify the molecular mechanisms underlying hypoxic regulation of cancer cell-CAF crosstalk. In addition, my studies will determine how activation of HIF1ɑ within CAFs regulates the tumor stroma and PDAC progression, which will inform targeting fibroblast HIF1ɑ as a potential therapeutic avenue to treat PDAC patients.

项目概要 胰腺导管腺癌（PDAC）是胰腺癌的一种常见形式，约占胰腺癌的 90% 这种疾病的所有病例。 PDAC 具有高度致命性，死亡率与发病率密切相关，主要是由于 无法在早期阶段诊断 PDAC 并对所有现有治疗方法产生耐药性。除了基因的改变 肿瘤细胞、肿瘤微环境在肿瘤的发生、进展和治疗中起着关键作用 反抗。 PDAC 以其致密的促纤维增生基质而闻名，该基质由细胞外基质、癌- 相关成纤维细胞（CAF）和免疫细胞。 PDAC 微环境的另一个显着特征是 缺氧，氧气供应不足的情况。尽管缺氧会导致两者的适应性反应 癌细胞和基质细胞，缺氧和缺氧诱导因子 1ɑ (HIF1ɑ)（一种主要调节因子）的影响 PDAC 基质和肿瘤基质相互作用的缺氧适应机制尚不完全清楚。我们有 最近发现，炎症性 CAF（iCAF）是产生高水平炎症细胞因子的 CAF 子集， 与人类和小鼠 PDAC 中的缺氧相关基因特征和 HIF1 信号通路有关。 通过将胰腺肿瘤细胞和成纤维细胞的 3D 共培养物暴露于缺氧或常氧条件下，我们 证明缺氧通过肿瘤细胞分泌的 IL1ɑ 促进 iCAF 形成。重要的是， 缺氧成纤维细胞的存在进一步升高了肿瘤细胞中的 IL1ɑ 水平，表明缺氧是 肿瘤细胞和成纤维细胞之间的双向相互作用。根据这些数据，我推测缺氧 通过调节 PDAC 中肿瘤细胞和成纤维细胞之间的双向相互作用来促进 iCAF 形成。 在具体目标 1 中，我将使用以下方法确定缺氧如何通过成纤维细胞诱导肿瘤细胞中的 IL1ɑ 表达： 胰腺肿瘤细胞和成纤维细胞的三维（3D）共培养系统，并将共培养物暴露于 缺氧或常氧。在具体目标 2 中，我将确定成纤维细胞 HIF1ɑ 是否以及如何调节肿瘤 使用肿瘤细胞和成纤维细胞的 3D 共培养物研究细胞-成纤维细胞相互作用和胰腺肿瘤发生 缺乏 HIF1ɑ，并使用缺乏 HIF1ɑ 成纤维细胞表达的小鼠模型。我的工作将确定 癌细胞-CAF 串扰低氧调节的分子机制。此外，我的学习将 确定 CAF 内 HIF1ɑ 的激活如何调节肿瘤基质和 PDAC 进展，这将 告知靶向成纤维细胞 HIF1ɑ 作为治疗 PDAC 患者的潜在治疗途径。