In vivo model of hypoxia in Ewing Sarcoma

尤文肉瘤缺氧体内模型

• 批准号: 8570304
• 负责人: Joanna B. Kitlinska
• 金额: $ 7.78万
• 依托单位: GEORGETOWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8570304
• 关键词: Address; Adolescent; Affect; Aldehydes; Animal Model; Animals; Area; Basic Science; Binding; Biology; Cell Culture Techniques; Child; Childhood Solid Neoplasm; Clinical; Clinical Data; Clinical Management; Clinical Sciences; Data; Development; Diagnosis; Disease; Disease Outcome; Disease Progression; Disease-Free Survival; EWS-FLI1 fusion protein; Environment; Ewings sarcoma; Excision; Exposure to; Family; Figs - dietary; Future; Gastrocnemius Muscle; Gene Targeting; Genes; Growth; Homeostasis; Human; Hydrogenase; Hypoxia; In Vitro; Ischemia; Lead; Ligation; Lung; Magnetic Resonance Imaging; Malignant - descriptor; Malignant Neoplasms; Metastatic Ewing' s Sarcoma; Metastatic Neoplasm to the Bone; Metastatic Neoplasm to the Lung; Modeling; Molecular; Monitor; Mus; Neoplasm Metastasis; Oxygen; Patients; Pattern; Periodicals; Pimonidazole; Prevention; Primary Neoplasm; Process; Prognostic Factor; Property; Regulation; Research; Research Design; Role; Solid; Solid Neoplasm; Testing; Time; Tumor Tissue; Xenograft procedure; aldehyde dehydrogenases; base; bone; bone invasion; cancer stem cell; femoral artery; hypoxia inducible factor 1; improved; in vivo Model; malignant phenotype; metastatic process; neoplastic cell; neuropeptide Y; novel; novel strategies; novel therapeutics; outcome forecast; prevent; public health relevance; response; sham surgery; therapy design; tool; transcription factor; tumor; tumor microenvironment; tumor progression; tumor xenograft; tumorigenic

DESCRIPTION (provided by applicant): Ewing's sarcoma family of tumors (ESFT) is a group of highly aggressive malignancies, the treatment of which remains an unsolved clinical problem. The presence of metastases is the single most powerful adverse prognostic factor for ESFT, with event-free survival at 72% and 27% for patients with localized and metastatic disease, respectively. The most unfavorable prognosis is associated with the presence of bone metastases. Thus, the treatment of metastatic ESFT and preventing disease dissemination is a crucial problem in ESFT clinical management. Despite that, however, the mechanisms governing the metastases formation in ESFT are poorly understood. Hypoxia has been implicated in ESFT progression by clinical and experimental data. In ESFT patients, the presence of unperfused areas within tumor tissue associates with an unfavorable metastatic pattern (multiple metastases with bone involvement), while the lack of such areas with better prognosis. In cell culture, hypoxia has been shown to up-regulate EWS-FLI1, an aberrant transcription factor triggering ESFT development, and shift its transcriptional activity toward pro metastatic and pro-survival genes. On functional levels, low oxygen augments ESFT cell invasiveness and tumorigenic potential. We have also shown hypoxia-induced enrichment in ESFT cells with a high activity of aldehyde dehydrogenase (ALDH), characterized as cancer stem cells, as well as identified neuropeptide Y (NPY), an EWS-FLI1 target gene, as a candidate hypoxia-induced pro-metastatic factor in ESFT. NPY has also been implicated in the regulation of bone homeostasis, suggesting its potential role in bone invasion. Based on these data, we hypothesize that hypoxia in primary tumor promotes ESFT metastases formation and changes their pattern by favoring bone invasion. To provide a direct proof for this notion, we propose developing a novel animal model by performing femoral artery ligation (FAL) in mice bearing orthotopic ESFT xenografts in their gastrocnemius muscles, followed by excision of the primary tumor and long-term monitoring of metastases formation. This approach will allow us to create transient hypoxia in growing ESFT tumor and test its effect on disease dissemination. The aims of our study are: 1) to establish a model of hypoxia in ESFT primary tumor by testing the impact of FAL on the oxygen level within tumor tissue; 2) to determine the effect of hypoxia on metastases formation by comparing number, sizes, latency and localization of metastases in animals with or without hypoxic challenge. Our study will provide direct proof for the role of hypoxia in ESFT metastases formation and disease progression. It will also establish a model that allows for testing factors already implicated in hypoxia-induced metastases formation, such as NPY, and identifying novel molecules involved in this process. This, in turn, will significantl improve our understanding of the metastatic processes in ESFT and address one of the most critical, yet understudied problems in its biology. In the future, this may result in the development of novel therapeutic strategies and prognostic factors, directly benefitting ESFT patients.

描述（由申请人提供）：尤文氏肉瘤家族肿瘤（ESFT）是一组高度侵袭性的恶性肿瘤，其治疗仍然是一个未解决的临床问题。 转移的存在是 ESFT 的一个最强大的不良预后因素，局部和转移性疾病患者的无事件生存率分别为 72% 和 27%。 最不利的预后与骨转移的存在有关。 因此，治疗转移性ESFT并预防疾病传播是ESFT临床管理中的一个关键问题。 然而，尽管如此，人们对 ESFT 转移形成的机制知之甚少。 临床和实验数据表明缺氧与 ESFT 进展有关。 在 ESFT 患者中，肿瘤组织内存在未灌注区域与不利的转移模式（累及骨的多发转移）相关，而缺乏此类区域则预后较好。 在细胞培养中，缺氧已被证明会上调 EWS-FLI1（一种触发 ESFT 发育的异常转录因子），并将其转录活性转向亲 转移和促生存基因。 在功能水平上，低氧会增强 ESFT 细胞的侵袭性和致瘤潜力。 我们还展示了缺氧诱导的 ESFT 细胞富集，其具有高活性的乙醛脱氢酶 (ALDH)，其特征为癌症干细胞，并鉴定了神经肽 Y (NPY)（一种 EWS-FLI1 靶基因），作为 ESFT 中缺氧诱导的候选促转移因子。 NPY 还涉及骨稳态的调节，表明其在骨侵袭中的潜在作用。 基于这些数据，我们假设原发肿瘤中的缺氧促进了 ESFT 转移的形成，并通过有利于骨侵袭来改变其模式。 为了为这一观点提供直接证据，我们建议通过对腓肠肌中携带原位 ESFT 异种移植物的小鼠进行股动脉结扎（FAL），然后切除原发肿瘤并长期监测转移形成，开发一种新型动物模型。 这种方法将使我们能够在生长的 ESFT 肿瘤中产生短暂的缺氧，并测试其对疾病传播的影响。 我们研究的目的是：1）通过测试FAL对肿瘤组织内氧水平的影响，建立ESFT原发肿瘤缺氧模型； 2) 通过比较有或没有缺氧挑战的动物中转移瘤的数量、大小、潜伏期和定位来确定缺氧对转移形成的影响。 我们的研究将为缺氧在 ESFT 转移形成和疾病进展中的作用提供直接证据。 它还将建立一个模型，允许测试已经与缺氧诱导的转移形成有关的因素，例如 NPY，并识别参与该过程的新分子。 反过来，这将显着提高我们对 ESFT 转移过程的理解，并解决其生物学中最关键但尚未得到充分研究的问题之一。 未来，这可能会导致新的治疗策略和预后因素的开发，直接使 ESFT 患者受益。