INTEGRIN SIGNALING DURING BREAST TUMORIGENESIS

乳腺癌肿瘤发生过程中的整合素信号传导

• 批准号: 7749542
• 负责人: FILIPPO G GIANCOTTI
• 金额: $ 38.96万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7749542
• 关键词: 1-Phosphatidylinositol 3-Kinase; Ablation; Adherens Junction; Adhesions; Apoptosis; Biochemical; Biological Assay; Breast Cancer Cell; Breast Carcinoma; Bypass; Cancer cell line; Carcinoma; Cells; Complex; ERBB2 gene; Endothelial Cells; Epithelial; Epithelial Cells; Extracellular Matrix; Fatty acid glycerol esters; Fibroblasts; Focal Adhesion Kinase 1; Genetic; Goals; Growth; Image; In Vitro; Integrins; Invaded; JUN gene; Laboratories; Maintenance; Malignant Epithelial Cell; Malignant Neoplasms; Mammary Neoplasms; Mammary Tumorigenesis; Mammary gland; Mediating; Modeling; Molecular; Molecular Target; Mus; Mutagenesis; Mutation; NOD/SCID mouse; Null Lymphocytes; Oncogenes; Oncogenic; Pathogenesis; Pathway interactions; Play; Polyomavirus; Proliferating; Public Health; Role; STAT3 gene; Signal Pathway; Signal Transduction; Specificity; Testing; Transgenic Mice; Tumorigenicity; adhesion receptor; breast tumorigenesis; cancer cell; cell transformation; design; imaging modality; in vivo; knock-down; macrophage; malignant breast neoplasm; mouse model; mutant; neoplastic cell; novel; reconstitution; research study; response; senescence; transcription factor; tumor; tumor initiation; tumor progression; tumorigenesis; tumorigenic

DESCRIPTION (provided by applicant): We hypothesize that integrin signaling plays key roles during tumor initiation and progression. To study the role of the ¿4 integrin during ErbB2-mediated mammary tumorigenesis, we introduced a targeted deletions of the ¿4 signaling domain in MMTV-Neu mice. Loss of ¿4 signaling delayed tumor onset and inhibited invasive growth. Ex vivo studies indicated that ¿4 forms a complex with ErbB2 and enhances activation of STAT3 and c-Jun. STAT3 contributes to disrupt epithelial adhesion and promote invasion, whereas c-Jun is required for hyperproliferation. To examine the role of Focal Adhesion Kinase (FAK) in mammary tumorigenesis, we introduced a mammary gland-specific ablation of FAK in MMTV-PyMT mice. Notably, deletion of FAK completely suppressed mammary tumorigenesis. In addition, silencing of FAK induced Ras- and PI-3K-transformed mammary carcinoma cells to undergo growth arrest and senescence or apoptosis in vitro. These results suggest that ¿4 promotes tumor progression by amplifying ErbB2 signaling, whereas FAK is required for Ras- and PI-3K-mediated mammary tumorigenesis. We propose: 1) To examine the oncogene specificity of the pro-tumorigenic effects of ¿4 and FAK. Normal mammary epithelial cells will be altered in vitro to suppress FAK or ¿4 signaling and then subjected to transformation assays with various oncogenes. Conversely, mammary tumor cells carrying distinct oncogenes will be genetically manipulated in vitro to suppress FAK or ¿4 signaling and subjected to assays designed to examine their ability to proliferate, to resist apoptosis, to invade in vitro, and to form orthotopic tumors in NOD/SCID mice. Key observations will be confirmed using selected human breast cancer cell lines and transgenic mouse models; 2) To elucidate the mechanisms through which ¿4 signaling disrupts epithelial adhesion and promotes invasion. The mechanism by which ¿4 amplifies ErbB2 signaling will be examined by using mutagenesis in combination with biochemical analysis and iRNA-mediated inhibition. The signaling pathways through which hyperactivation of Rac causes disassembly of adherens junctions will be studies by using biochemical analysis, silencing, and imaging methods; 3) To study the molecular mechanisms through which FAK promotes mammary tumorigenesis. Silencing will be used to confirm that CAS mediates the pro-tumorigenic effect of FAK. Biochemical analysis of control and CAS-silenced tumor cells will then be used to identify CAS-dependent pathways. Inhibition of key downstream effectors will be used to identify the major signaling pathways through which CAS promotes mammary tumorigenesis; 4) To examine the mechanisms through which ¿4 and FAK cooperate to sustain ErbB2-initiated mammary tumorigenesis. Biochemical experiments will be conducted to identify signaling components jointly activated by ¿4 and FAK in mammary tumor cells. Silencing will be used to test the pro-tumorigenic role of potential key signaling integrators. Mouse genetics will be used to determine if ¿4 and FAK cooperate in vivo to promote ErbB2-initiated mammary tumorigenesis. PUBLIC HEALTH RELEVANE: Breast carcinoma cells evolve toward increasing malignancy in response to signals from their microenvironment, which include carcinoma-associated fibroblasts, macrophages, angiogenic endothelial cells, and the extracellular matrix that these cells produce. The integrin adhesion receptors are critical players in this signaling network. Yet, their role in breast tumorigenesis is incompletely understood. Our preliminary studies suggest that the ¿4 integrin promote breast carcinoma progression by amplifying ErbB2 signaling, whereas Focal Adhesion Kinase (FAK) is required for Ras- and Pi-3K-mediated tumor initiation and maintenance. We propose to examine the mechanisms through which ¿4 and FAK promote breast tumorigenesis. These studies will contribute to our understanding of the pathogenesis of breast cancer and to the identification of novel molecular targets for its therapy.

描述（由应用程序提供）：我们假设整联蛋白信号传导在肿瘤开始和进展过程中起关键作用。为了研究€4整联蛋白在ERBB2介导的乳腺肿瘤发生过程中的作用，我们引入了MMTV-NEU小鼠中4个信号域的靶向缺失。 »4信号传导的丧失延迟肿瘤发作并抑制浸润性生长。离体研究表明，€4与ERBB2形成复合物，并增强了STAT3和C-JUN的激活。 STAT3有助于破坏上皮粘附并促进侵袭，而c-Jun是过度增殖所必需的。为了检查局灶性激酶（FAK）在乳腺结核病中的作用，我们引入了MMTV-PYMT小鼠中FAK的乳腺特异性消融。值得注意的是，FAK的缺失完全抑制了乳腺结核病。此外，FAK降温诱导的RAS和PI-3K转化的乳腺癌细胞会在体外经历生长停滞和感应或凋亡。这些结果表明，„ 4通过扩增ERBB2信号传导促进肿瘤进展，而RAS和PI-3K介导的乳腺肿瘤发生需要FAK。我们建议：1）检查€4和fak的亲氧化作用的癌基因特异性。正常的乳腺上皮细胞将在体外改变以抑制FAK或€4信号传导，然后对各种致癌基因进行转化测定。相反，携带不同癌基因的乳腺肿瘤细胞将在遗传上受到遗传操纵，以抑制FAK或4信号传导，并受到旨在检查其在NOD/SCID小鼠中抗凋亡，抗凋亡，体外侵袭并形成原始肿瘤的旨在检查其增殖能力。将使用选定的人类乳腺癌细胞系和转基因小鼠模型确认关键观察结果。 2）阐明了„ 4信号传导破坏上皮粘附并促进入侵的机制。通过将诱变与生化分析和IRNA介导的抑制结合使用诱变，将检查4个放大器ERBB2信号传导的机制。通过使用生化分析，沉默和成像方法，将研究RAC过度激活导致粘膜连接拆卸的信号传导途径。 3）研究FAK促进乳腺肿瘤发生的分子机制。静音将用于确认CAS介导FAK的亲肿瘤效应。然后，将使用对对照和CAS有毛的肿瘤细胞的生化分析来鉴定CAS依赖性途径。抑制关键下游效应将用于确定CAS促进乳腺肿瘤发生的主要信号传导途径。 4）检验``4和FAK合作''ERBB2引起的乳腺肿瘤发生的机制。将进行生化实验，以识别乳腺肿瘤细胞中共同激活的信号成分和FAK共同激活。静音将用于测试潜在的钥匙信号积分器的促肿瘤作用。小鼠遗传学将用于确定4和FAK在体内是否合作以促进ERBB2引起的乳腺肿瘤发生。与公共卫生相关的：乳腺癌细胞旨在响应其微环境的信号而发展，其中包括与癌相关的成纤维细胞，巨噬细胞，血管生成内皮细胞以及这些细胞产生的细胞外基质。整联蛋白粘合剂受体是此信号网络中的关键参与者。然而，它们在乳腺肿瘤发生中的作用尚不完全理解。我们的初步研究表明，€4整联蛋白通过扩增ERBB2信号传导促进乳腺癌的进展，而RAS和PI-3K介导的肿瘤启动和维持需要局灶性粘附激酶（FAK）。我们建议研究``4 and fak''和fak促进乳腺肿瘤发生的机制。这些研究将有助于我们理解乳腺癌的发病机理以及鉴定其治疗的新分子靶标。