Function of ACAP4 in CCL18-stimulated breast cancer metastasis

描述(申请人提供)：转移，癌症扩散，通常是实体恶性肿瘤发展的最后和致命的阶段。对于那些有远处转移的妇女来说，早期发现局部乳腺癌导致较高的相对五年生存率(98%)，而相对五年生存率显着下降(26%)。因此，更好地理解该病发生和发展的机制洞察力在临床环境中是极其重要的。我们的研究表明，从肿瘤相关巨噬细胞释放的细胞因子CCL18促进乳腺癌转移，并作为临床肿瘤学中生存不良的新指标(Chen等人，2011年)。癌细胞)。此外, 我们最近的研究发现了一个涉及CCL18及其潜在效应因子ARF6-ACAP4-Ezrin的乳腺癌转移信号网络。然而，关于CCL18在乳腺癌转移中的分子机制(S)知之甚少。我们研究的长期目标是描绘ARF6-ACAP4-Ezrin相互作用如何协调刺激耦合的乳腺癌转移。为了解决这个问题，我们提出了三个具体的目标：第一，我们将使用结合ACAP4小分子抑制剂的新型生物传感器来描绘乳腺癌细胞动力学背后的ARF6活性梯度；第二，我们将使用表位标记、化学足迹和交联法来评估磷酸化Ezrin如何与ACAP4相互作用。这些研究将涉及对介导Ezrin-ACAP4直接接触的结构决定因素的详细分析。结合结构域数据将被用来设计在体外结合试验中有效和特异地干扰Ezrin-ACAP4相互作用的多肽。这种相互作用在乳腺癌侵袭中的重要性将通过功能分析和超分辨率成像分析来评估。第三，我们计划研究ACAP4介导的乳腺癌在动物体内相互作用的潜在机制。这些研究将通过活体生物发光图像和小分子抑制剂在活体异种移植动物中的治疗来促进。研究乳腺癌转移的分子机制对了解实体瘤的进展具有重要意义，也有望对指导预防肿瘤细胞扩散的药物策略具有重要意义。

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.