Function of ACAP4 in CCL18-stimulated breast cancer metastasis

描述（由申请人提供）：转移，癌症扩散，通常是实体恶性肿瘤进展的最终和致命阶段。局部乳腺癌的早期发现导致较高的相对五年生存率（98%），而对于那些有远处转移的妇女，相对五年生存率显著下降（26%）。因此，更好地了解关于这种疾病的发展和进展的机制见解在临床环境中是极其重要的。我们的研究揭示，从肿瘤相关巨噬细胞释放的细胞因子CCL 18促进乳腺癌转移，并在临床肿瘤学中充当存活率差的新指标（Chen et al.，2011. Cancer Cell）。此外，本发明还提供了一种方法， 我们最近的研究鉴定了涉及CCL 18及其潜在效应物ARF 6-ACAP 4-ezrin的乳腺癌转移信号传导网络。然而，关于CCL 18在乳腺癌转移中起作用的分子机制知之甚少。我们研究的长期目标是描述ARF 6-ACAP 4-ezrin相互作用如何协调刺激偶联的乳腺癌转移。为了解决这个问题，提出了三个具体的目标：首先，我们将描绘的ARF 6活性梯度乳腺癌细胞动力学使用一种新的生物传感器结合ACAP 4小分子抑制剂;其次，我们评估磷酸埃兹蛋白如何与ACAP 4使用表位标签，化学足迹，和交联方法相互作用。这些研究将涉及介导直接ezrin-ACAP 4接触的结构决定因素的详细分析。结合结构域数据将用于设计在体外结合测定中有效且特异性地干扰ezrin-ACAP 4相互作用的肽。这种相互作用在乳腺癌侵袭中的重要性将通过功能测定和超分辨率成像分析来评估。第三，我们计划在动物中研究ACAP 4介导的乳腺癌相互作用的潜在机制。这些研究将通过在活体异种移植动物中结合小分子抑制剂治疗的体内生物发光图像来促进。 研究乳腺癌转移的分子机制对于了解实体瘤的进展具有重要意义，并且预计也将对预防肿瘤细胞扩散的药理学策略产生巨大益处。 公共卫生相关性：提出的调查线代表了一个高度集成的翻译努力，描绘乳腺肿瘤转移，并提供了一个战略，疾病干预。

DESCRIPTION (provided by applicant): Metastasis, cancer spreading, is often a final and fatal stage in the progression of solid malignancies. Early detection of localized breast cancer results in a higher relative five-year survival rate (98%) while the relative five-year survival rae drops significantly (26%) for those women who have distant metastases. Therefore, a better understanding of mechanistic insight regarding the development and progression of this disease is of extreme importance in clinical setting. Our study revealed that cytokine CCL18 released from tumor-associated macrophage promotes breast cancer metastasis and serves as a novel indicator for poor survival in the clinical oncology (Chen et al., 2011. Cancer Cell). In addition, our recent study identified a breast cancer metastasis signaling network involving CCL18 and its potential effectors ARF6-ACAP4-ezrin. However, little is known regarding the molecular mechanism(s) by which CCL18 operates in breast cancer metastasis. The long-term goal of our research is to delineate how ARF6-ACAP4-ezrin interaction orchestrates stimulus-coupled breast cancer metastasis. To address this question, three Specific Aims are proposed: first, we will delineate the ARF6 activity gradient underlying breast cancer cell dynamics using a novel biosensor combined with ACAP4 small molecule inhibitors; second, we evaluate how phospho-ezrin interacts with ACAP4 using epitope-tagging, chemical foot-printing, and cross-linking approaches. These studies will involve a detailed analysis of the structural determinants that mediate a direct ezrin-ACAP4 contact. Binding domain data will be used to design peptides that potently and specifically perturb ezrin-ACAP4 interactions in in vitro binding assays. The importance of such an interaction in breast cancer invasion will then be evaluated by functional assay and supra-resolution imaging analysis. Third, we plan to investigate the potential mechanisms underlying ACAP4-mediated breast cancer interacts in animals. These studies will be facilitated by in vivo bioluminescence images coupled with small molecule inhibitor treatment in live xenografted animals. Studying the molecular mechanisms underlying breast cancer metastasis is of great significance in understanding the solid tumor progression, and is also expected to be of great benefit in leading to pharmacological strategies for preventing tumor cell spreading. PUBLIC HEALTH RELEVANCE: The proposed line of investigations represents a highly integrated translational effort to delineate breast tumor metastasis and provide a strategy for disease intervention.