Prometastatic Effects of Neoadjuvant Chemotherapy in Breast Cancer

项目摘要 转移，即癌细胞从原发性肿瘤向继发部位的扩散，是肿瘤转移的主要原因。 癌症相关死亡率。虽然化疗可以提高早期乳腺癌的总生存率，但它不能 为转移提供明确的治疗。特别地，化疗诱导肿瘤的促转移变化， 如果在术前（新辅助）环境中给药，这些促转移的变化是 主要通过促血管生成的Tie 2 Hi巨噬细胞浸润肿瘤而启动， 肿瘤转移微环境（TMEM）是癌细胞内渗部位的一个重要组成部分。只 表达MenaINV侵袭性和迁移性癌细胞可以通过TMEM扩散。小鼠乳腺 在肿瘤和患者来源的异种移植物中，新辅助化疗增加了（i）TMEM组装，（ii）TMEM组装，（iii）TMEM组装，（iv）TMEM组装。 表达MenaINV的癌细胞的密度，（iii）循环肿瘤细胞的数目，和（iv）肺转移。 这项建议将阐明化疗发挥这些促转移作用的分子机制。 乳腺肿瘤微环境的变化，因此预测性生物标志物和靶向信号通路 “化疗诱导的转移”的可能性。我们假设巨噬细胞募集到 新辅助化疗后的肿瘤不仅使肿瘤细胞具有传播能力， 诱导MenaINV表达，但也获得肿瘤启动能力 负责肿瘤生长的启动在遥远的网站。在目标1中，我们将研究巨噬细胞癌是否 细胞相互作用是诱导MenaINV和MenaINV介导的促转移表型所必需的， 新辅助化疗治疗。这将使用已建立的巨噬细胞耗竭来完成 体内研究，再加上先进的显微镜。在目标2中，我们将研究乳腺肿瘤细胞是否 表达MenaINV-Hi也具有干细胞能力。表达荧光干细胞的MDA-MB-231细胞 报告基因（SORE 6）将用于产生异种移植物，用于多光子活体成像显微镜检查和固定- 组织多通道免疫荧光显微镜，研究新辅助化疗对 肿瘤细胞干细胞性目的3旨在解开负责上述信号通路 促转移表型。转基因和药理学抑制小鼠模型靶向相关 将开发阿曲他克林途径以消除巨噬细胞-肿瘤细胞相互作用，并研究是否 这些途径在化疗诱导的转移中起作用。阿尔伯特的研究环境 爱因斯坦医学院为合作、科学讨论和 职业发展。拟议的研究和职业发展培训加上一个特殊的团队 先进显微镜专家Condeelis博士、内科科学家Oktay博士、医学先驱韦克菲尔德博士 干细胞研究和巨噬细胞生物学领导人理查德·斯坦利博士将确保我实现我的目标 在一所重点大学建立一个成功的独立资助的实验室。

Project Summary Metastasis, the dissemination of cancer cells from the primary tumor to secondary sites, is the leading cause of cancer-related mortality. Although chemotherapy improves overall survival in early breast cancer, it does not provide definite cure for metastasis. Paradoxically, chemotherapy induces pro-metastatic changes in the tumor microenvironment if given in the pre-operative (neo-adjuvant) setting. These pro-metastatic changes are primarily initiated via infiltration of tumors by pro-angiogenic Tie2Hi macrophages, which are essential components of cancer cell intravasation sites called Tumor MicroEnvironment of Metastasis (TMEM). Only invasive and migratory cancer cell expressing MenaINV can disseminate via TMEM. In mouse mammary carcinoma and patient derived xenografts, neo-adjuvant chemotherapy increases (i) TMEM assembly, (ii) the density of cancer cells expressing MenaINV, (iii) the number of circulating tumor cells, and (iv) lung metastases. This proposal will elucidate molecular mechanisms by which chemotherapy exerts these pro-metastatic changes in the breast tumor microenviroment, so that predictive biomarkers and targetable signaling pathways of “chemotherapy-induced metastasis” can be identified. We hypothesize that macrophages recruited to tumors upon neo-adjuvant chemotherapy educate tumor cells not only to become dissemination-competent by inducing MenaINV expression through juxtacrine interactions, but also to obtain tumor-initiating capabilities responsible for tumor growth initiation at distant sites. In Aim 1, we will investigate whether macrophage-cancer cell interaction is required for induction of MenaINV and MenaINV-mediated pro-metastatic phenotypes upon treatment with neo-adjuvant chemotherapy. This will be accomplished using established macrophage depletion studies in vivo, coupled with advanced microscopy. In Aim 2, we will investigate whether breast tumor cells expressing MenaINV-Hi also harbor stem cell capabilities. MDA-MB-231 cells expressing a fluorescent stem cell reporter (SORE6) will be used to generate xenografts for multiphoton intravital imaging microscopy and fixed- tissue multichannel immune-fluorescent microscopy and study the effects of neo-adjuvant chemotherapy on tumor cell stemness. Aim 3 is designed to unravel the signaling pathways responsible for the aforementioned pro-metastatic phenotypes. Transgenic and pharmacological inhibition mouse models targeting the relevant juxtacrine pathways will be developed to eliminate macrophage-tumor cell interactions and study whether these pathways are instrumental in chemotherapy-induced metastasis. The research environment at the Albert Einstein College of Medicine offers outstanding opportunities for collaborations, scientific discussion and career development. The proposed studies and career development training coupled with an exceptional team of Dr. Condeelis, expert in advanced microscopy, Dr. Oktay, physician scientist, Dr. Wakefield a pioneer in stem cell research, and Dr. Richard Stanley, leader in macrophage biology, will ensure that I achieve my goal of establishing a successful, independently-funded lab at a major university.