Reactivation of breast cancer micrometastases by senescent bone marrow stroma

衰老骨髓基质重新激活乳腺癌微转移

• 批准号: 7740228
• 负责人: ROBERT WIEDER
• 金额: $ 20.59万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-19 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7740228
• 关键词: Aging; Anti-Inflammatory Agents; Anti-inflammatory; Bone Marrow; Breast Cancer Cell; Cancer Patient; Chemical Injury; Chemicals; Coculture Techniques; Cytokine Activation; Cytotoxin; Data; Dependence; Development; Diagnosis; Disease; Estrogen Replacements; Estrogens; Goals; Hypoxia; IL8 gene; In Vitro; Inflammation; Inflammatory; Injection of therapeutic agent; Injury; Interleukin-6; Investigation; Left; Left ventricular structure; Measures; Micrometastasis; Modeling; Mus; Neoplasm Metastasis; Osteoclasts; Phenotype; Postmenopause; Receptor Signaling; Recovery; Recurrence; Soil; Source; Staging; Stress; Stromal Cells; Testing; Thinking; Time; Validation; Woman; Xenograft procedure; cancer cell; cancer recurrence; cytokine; cytotoxicity; deprivation; in vitro Model; in vivo; inhibitor/antagonist; malignant breast neoplasm; molecular marker; monolayer; novel strategies; prevent; public health relevance; research study; senescence

DESCRIPTION (provided by applicant): More than a third of stage I-III breast cancer patients have bone marrow micrometastases at the time of diagnosis providing a source of recurrence. Most recurrences occur in post-menopausal women. Mechanisms of dormancy and recurrence are not well understood, but data suggest a dependence on a close association with bone marrow stroma. We hypothesize that stromal cells undergo senescence due to aging and/or post-menopausal estrogen deprivation and begin to secrete inflammatory cytokines that can stimulate dormant cancer cells to re-awaken. The broad, long-term goals of our investigations are to define mechanisms that govern the establishment of the dormant state in breast cancer cells in the bone marrow and to determine factors and mechanisms responsible for their re-awakening and recurrence of disease. We propose to determine if bone marrow stroma can undergo senescence when deprived of estrogen or treated with cytotoxins in vitro and in vivo in a murine model. Our specific aims are: 1. to determine if in vitro estrogen deprivation can induce a senescent phenotype in bone marrow stromal cultures incapable of supporting breast cancer dormancy in an in vitro model and 2. to determine if in vivo estrogen deprivation induces a senescent phenotype in bone marrow stroma rendering it incapable of supporting breast cancer dormancy in vitro and in vivo. We will establish and characterize the phenotype of secretory senescence by subjecting stromal monolayers to oxidative and hypoxic stress and estrogen deprivation and measure the expression and activation of TGF¿, Cox-2, IL-6, IL-8 and SA-¿Gal, known markers associated with senescence. We will determine if estrogen deprivation in vitro and in vivo and cytotoxicity in vitro can induce senescence measured by these molecular markers and by the loss of support of breast cancer dormancy in an in vitro clonogenic co-culture model and in a left ventricle injection bone marrow metastasis model. Experiments will also determine whether estrogen-deprivation renders stroma more susceptible to chemical injury and whether administration of Cox-2 inhibitors or estrogen can reverse these effects. These studies will establish a way of thinking about dormancy as a function of the senescent microenvironment and seek to reverse estrogen-deprivation-induced inflammation to maintain it. PUBLIC HEALTH RELEVANCE: The proposed study will investigate the induction of senescence in mouse bone marrow stroma by estrogen deprivation in vitro and in vivo as manifested by the secretion of inflammatory cytokines and loss of the capacity to support dormancy of breast cancer cells in an in vitro model and the loss of the capacity to support the dormancy of xenografted human breast cancer cells in the bone marrow microenvironment. Experiments will determine if treatment with estrogen or anti-inflammatory agents can restore the capacity of senescent stroma to support dormancy.

描述（由申请人提供）：超过三分之一的I-III期乳腺癌患者在诊断时有骨髓微转移，这是复发的来源。 大多数复发发生在绝经后妇女。 休眠和复发的机制尚不清楚，但数据表明与骨髓基质密切相关。 我们假设基质细胞由于衰老和/或绝经后雌激素缺乏而经历衰老，并且开始分泌炎性细胞因子，其可以刺激休眠的癌细胞重新唤醒。 我们研究的广泛，长期目标是确定管理骨髓中乳腺癌细胞休眠状态建立的机制，并确定导致其重新觉醒和疾病复发的因素和机制。 我们建议，以确定是否骨髓基质可以进行衰老时，剥夺雌激素或细胞毒素治疗在体外和体内的小鼠模型。 我们的具体目标是：1.以确定体外雌激素剥夺是否可以在体外模型中诱导不能支持乳腺癌休眠的骨髓基质培养物中的衰老表型，以及2.以确定体内雌激素剥夺是否诱导骨髓基质中的衰老表型，使其不能在体外和体内支持乳腺癌休眠。 我们将通过使基质单层经受氧化和缺氧应激以及雌激素剥夺来建立和表征分泌性衰老的表型，并测量已知的与衰老相关的标记物TGF β、考克斯-2、IL-6、IL-8和SA-β Gal的表达和活化。 我们将确定体外和体内雌激素剥夺和体外细胞毒性是否可以诱导衰老，通过这些分子标志物和体外克隆共培养模型和左心室注射骨髓转移模型中乳腺癌休眠支持的丧失来测量。 实验还将确定雌激素缺乏是否会使基质对化学损伤更敏感，以及施用考克斯-2抑制剂或雌激素是否可以逆转这些作用。这些研究将建立一种思考休眠作为衰老微环境的功能的方式，并寻求逆转雌激素剥夺诱导的炎症以维持它。本研究将在体外和体内研究雌激素剥夺诱导小鼠骨髓基质衰老，表现为炎症细胞因子的分泌和支持细胞休眠能力的丧失。乳腺癌细胞在体外模型和支持异种移植的人乳腺癌细胞在骨髓微环境中休眠的能力的丧失。 实验将确定用雌激素或抗炎剂治疗是否能恢复衰老基质支持休眠的能力。