Investigating L1CAM-dependent stem cell regeneration in metastasis

项目总结 转移性癌症总是复发，因为出现了能够自我复制的耐药亚克隆。 更新、缓慢的细胞周期、肿瘤的重新启动和治疗耐药，称为转移干细胞(MetSCs)。 然而，MetSCs用于生存和再生的分子机制还知之甚少。初步 本提案中描述的数据将细胞黏附分子细胞黏附分子L1(L1CAM)鉴定为 抑制转移复发的关键靶点。采用新的患者衍生的有机类药物治疗模式- 耐药结直肠癌(CRC)肝转移，L1CAM细胞在患者肿瘤中表现出选择性 在体外再生有机物质。L1CAM是有机物在体外再生所必需的，而小鼠 活体结肠炎损伤后的结肠上皮细胞。在完整的上皮结构中细胞-细胞接触的破坏 L1CAM诱导的必要条件和充分条件，随着时间的推移，表达随着时间的推移而减少，就像上皮一样 重生了。我们假设上皮细胞的不完整性诱导了L1CAM的表达，这是 癌细胞在侵袭、转移和后续治疗过程中的存活和再生长。这些机制可以 在肿瘤进展过程中诱导L1CAM依赖将被定义(1)使用患者衍生的器官模型 用来确定L1CAM在上皮连接下游的转录调控 分离和(2)使用基因工程小鼠模型，尖端器官衍生的原位移植 直肠移植和活体原位肝肺转移模型中L1CAM的作用 肿瘤的起始、局部侵袭、转移定植和维持。拟议的调查将 肿瘤扩散诱导表型可塑性及其产生的信号通路 并将为L1CAM靶向抑制肿瘤转移再生的药物铺平道路。这个 申请人，卡鲁纳·加内什博士，斯隆·凯特林纪念医院胃肠道肿瘤学服务的讲师 癌症中心(MSKCC)，制定了一项5年的职业计划，该计划建立在她在 内科肿瘤学生物化学与临床培训。该项目将为Ganesh博士提供理想的培训 在使用具有临床代表性的、最先进的患者衍生的器官和小鼠模型来解剖 转移的转录和表观遗传调控。加内什博士将由琼·马萨古博士指导，她是一名 国际知名的肿瘤转移专家，有良好的培训成功的独立记录 内科科学家。候选人的职业发展计划包括课程作业、研讨会、 由杰出的基础科学家和医学肿瘤学家组成的跨学科咨询委员会；以及 在MSKCC卓越的制度环境中的研究经验 转化性癌症研究。研究项目的成功完成将带来新的方法 治疗转移性癌症患者，将为加内什医生过渡到一个职位提供基础 作为一名独立调查员，她拥有自己的实验室和R01资金。

PROJECT SUMMARY Metastatic cancers invariably relapse due to the emergence of resistant subclones that are capable of self- renewal, slow cell-cycling, tumor re-initiation and therapy resistance, termed metastasis stem cells (MetSCs). Yet the molecular mechanisms MetSCs employ for survival and regrowth are poorly understood. Preliminary data described in this proposal identify the cell-adhesion molecule cell adhesion molecule L1 (L1CAM) as a critical target for suppressing metastatic relapse. Employing novel patient-derived organoid models of therapy- resistant colorectal cancer (CRC) liver metastases, L1CAM+ cells in patient tumors are shown to selectively regenerate organoids ex vivo. L1CAM is required for the regeneration of organoids in vitro, and the mouse colon epithelium after colitis injury in vivo. Disruption of cell-cell contact in intact epithelial structures is necessary and sufficient for L1CAM induction, with expression diminishing over time as the epithelium is regenerated. We hypothesize that epithelial disintegrity induces L1CAM expression, which is required for the survival and regrowth of cancer cells during invasion, metastasis and following therapy. The mechanisms that induce L1CAM dependency during tumor progression will be defined (1) using patient-derived organoid models of metastatic CRC to define the transcriptional regulation of L1CAM downstream of epithelial junction dissociation and (2) using genetically engineered mouse models, cutting-edge organoid-derived orthotopic rectal transplantation, and orthotopic liver and lung metastatic models in vivo to determine the role of L1CAM in tumor initiation, local invasion, metastatic colonization and maintenance. The proposed investigations will delineate signaling pathways by which tumor dissemination induces phenotypic plasticity and the emergence of metastatic traits, and will pave the way for L1CAM-targeting drugs that inhibit metastasis regeneration. The applicant, Dr. Karuna Ganesh, an Instructor in the Gastrointestinal Oncology Service at Memorial Sloan Kettering Cancer Center (MSKCC), has delineated a 5-year career plan that builds upon her research background in biochemistry and clinical training in medical oncology. This project will provide the ideal training for Dr. Ganesh in using clinically representative, state-of-the-art patient-derived organoid and mouse models to dissect the transcriptional and epigenetic regulation of metastasis. Dr. Ganesh will be mentored by Dr. Joan Massagué, an internationally renowned expert in metastasis with a strong track record of training successful independent physician scientists. The candidate's career development plan includes coursework, workshops, mentoring from an interdisciplinary advisory committee comprising distinguished basic scientists and medical oncologists, and research experience in the outstanding institutional environment of MSKCC, a center of excellence in translational cancer research. Successful completion of the research project will lead to new approaches for treating patients with metastatic cancer and will provide the foundation for Dr. Ganesh to transition to a position as an independent investigator with her own laboratory and R01 funding.