Genetic Analysis of FAK kinase and scaffold functions in breast cancer

乳腺癌中 FAK 激酶和支架功能的遗传分析

• 批准号: 8477152
• 负责人: JUN-LIN GUAN
• 金额: $ 30.33万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8477152
• 关键词: Affect; Alleles; Biological; Breast; Cell Adhesion; Cells; Development; Disease; Exhibits; Focal Adhesion Kinase 1; Genes; Genetic; Genomics; Goals; Growth Factor Receptors; Health; Human; Incidence; Integrins; Knock-in Mouse; Knock-out; MMP14 gene; Maintenance; Malignant Neoplasms; Mammary Neoplasms; Mammary Tumorigenesis; Mammary gland; Mediating; Modeling; Molecular; Mouse Mammary Tumor Virus; Mus; Mutant Strains Mice; Mutation; Neoplasm Metastasis; Oncogenes; Phosphorylation; Phosphotransferases; Play; Protein Tyrosine Kinase; Regulation; Role; Signal Pathway; Signal Transduction; Signaling Protein; Stem cells; Surface; Tumor Suppressor Genes; Tumorigenicity; Woman; base; cancer stem cell; cancer therapy; epithelial to mesenchymal transition; genetic analysis; in vivo; insight; malignant breast neoplasm; mammary epithelium; migration; mortality; mouse model; mutant; neoplastic cell; novel; scaffold; self-renewal; tumor; tumor growth; tumor initiation; tumor progression; tumorigenesis

DESCRIPTION (provided by applicant): Breast cancer exhibits enormous cellular, genomic and biological complexity wherein multiple gene aberrations act to drive tumorigenesis and cancer progression. The long term goal of the proposed studies is to understand the cellular and molecular mechanisms in the regulation of breast cancer development and metastasis. Focal adhesion kinase (FAK) is a cytoplasmic tyrosine kinase that plays a major role in mediating signal transduction by integrins as well as growth factor receptors in the regulation of cell adhesion, migration, survival, proliferation and differentiation in a variety of cells. FAK has been implicated in human breast cancer as well as other malignancies. However, the cellular and molecular mechanisms by which FAK promotes mammary tumorigenesis in vivo are still not well understood. We showed recently that conditional knockout of FAK in the mammary epithelium suppressed mammary tumorigenesis and progression by affecting MaCSCs in a well characterized breast cancer mouse model. To investigate the unique role of FAK as both a tyrosine kinase and a scaffold in intracellular signaling in breast cancer, we have recently created two novel FAK knock-in mutant mice with the kinase-defective allele (FAK +/KD mice) or the P878/881A mutation allele (FAK +/PA mice) to disrupt its signaling through tyrosine kinase activity or specific scaffolding function for endophilin A2 phosphorylation by Src and regulation of MT1-MMP, respectively. Preliminary analyses of the PA mutant knockin mice using the MMTV-PyMT model (PA/PA-MT mice) revealed that FAK mediated endophilin A2 phosphorylation by Src plays an important role in mammary tumor growth and metastasis by promoting epithelial to mesenchymal transition (EMT) of mammary tumor cells, and by maintaining the content and tumorigenicity of MaCSCs. In addition, we identified a function of FAK in the maintenance of normal MaSCs and found that kinase-independent functions of FAK were able to promote self-renewal of MaSCs. Lastly, we also obtained preliminary results suggesting an important role of FAK in regulation of human MaCSCs, which is consistent with our more extensive findings in mouse models. Based on these preliminary and previous studies, we propose to 1). determine the mechanism of FAK scaffold function in mammary tumor growth and metastasis through regulation of EMT and MaCSCs, 2). examine the role of FAK kinase activity and dissect the downstream kinase-dependent and -independent signaling pathways in breast cancer development and progression, and 3). explore the strategies of targeting FAK scaffold and kinase functions in MaCSCs for breast cancer therapy. Together, these studies will provide significant insights into the molecular and cellular mechanisms of breast cancer that may contribute to novel therapies for this devastating disease.

描述（由申请人提供）：乳腺癌表现出巨大的细胞、基因组和生物复杂性，其中多种基因畸变驱动肿瘤发生和癌症进展。拟议研究的长期目标是了解乳腺癌发展和转移调节的细胞和分子机制。粘着斑激酶 (FAK) 是一种细胞质酪氨酸激酶，在介导整合素和生长因子受体的信号转导中发挥重要作用，调节多种细胞的细胞粘附、迁移、存活、增殖和分化。 FAK 与人类乳腺癌以及其他恶性肿瘤有关。然而，FAK在体内促进乳腺肿瘤发生的细胞和分子机制仍不清楚。我们最近表明，在一个特征明确的乳腺癌小鼠模型中，条件性敲除乳腺上皮中的 FAK 可通过影响 MaCSC 来抑制乳腺肿瘤的发生和进展。为了研究 FAK 作为酪氨酸激酶和支架在乳腺癌细胞内信号传导中的独特作用，我们最近创建了两种新型 FAK 敲入突变小鼠，它们具有激酶缺陷等位基因（FAK +/KD 小鼠）或 P878/881A 突变等位基因（FAK +/PA 小鼠），通过酪氨酸激酶活性或内亲蛋白的特定支架功能来破坏其信号传导 A2 分别由 Src 磷酸化和 MT1-MMP 调节。使用MMTV-PyMT模型对PA突变敲入小鼠（PA/PA-MT小鼠）进行的初步分析表明，FAK介导的Src内皮素A2磷酸化通过促进乳腺肿瘤细胞的上皮向间质转化（EMT）、维持内皮素A2的含量和致瘤性，在乳腺肿瘤的生长和转移中发挥重要作用。 MaCSC。此外，我们还鉴定了FAK在维持正常MaSCs中的功能，并发现FAK的激酶独立功能能够促进MaSCs的自我更新。最后，我们还获得了初步结果，表明 FAK 在人类 MaCSC 的调节中发挥重要作用，这与我们在小鼠模型中更广泛的发现一致。基于这些初步和之前的研究，我们提出 1)。通过调节 EMT 和 MaCSC 确定 FAK 支架在乳腺肿瘤生长和转移中的功能机制，2)。检查 FAK 激酶活性的作用并剖析乳腺癌发生和进展中下游激酶依赖性和独立性信号通路，以及 3)。探索针对 MaCSC 中 FAK 支架和激酶功能的乳腺癌治疗策略。总之，这些研究将为乳腺癌的分子和细胞机制提供重要的见解，可能有助于为这种破坏性疾病提供新的治疗方法。