Human Breast Cancer Stem Cell Surrogates

描述(申请人提供)：有人建议，能够启动局部或远程复发的一小部分肿瘤细胞表现出干细胞的特性，并且假定的癌症干细胞的鉴定和分子特征将通过在适当选择的患者中进行靶向癌症干细胞治疗而导致更好的结果。检验这些细胞的预测和预后意义的临床研究受到多种因素的限制，包括从组织中分离单个细胞的方法不同，需要多个标记物来区分承诺细胞和未分化细胞，以及是否有患者的新鲜组织可供研究。起源于原发肿瘤的循环肿瘤细胞(在血液中)和播散性肿瘤细胞(在骨髓中)是有吸引力的癌症干细胞候选者，也是癌症干细胞研究的实用临床替代物，因为它们以单个细胞的形式存在，并且可以使用FDA批准的现有技术进行量化。因此，我们提出了一种翻译策略来检测乳腺癌患者的原发、循环和播散性肿瘤细胞，以验证我们的中心假设，即存在于非转移性乳腺癌患者血液和骨髓中的循环和播散性肿瘤细胞代表癌症干细胞，这些干细胞是远处转移的前驱细胞，也是新治疗的潜在靶点。我们的假设基于一项正在进行的IRB批准的临床方案的初步数据，该方案证明非转移性乳腺癌患者骨髓中的播散性肿瘤细胞对肿瘤启动能力的癌症干细胞标志物CD44+CD24-和乙醛脱氢酶-1(ALDH1)的表达呈阳性。翻译目标基于三个IRB方案，并针对每个试验中收集的材料、治疗方法和患者群体而量身定制。这项翻译工作代表了乳腺医学肿瘤学的Massimo Cristofanilli、詹姆斯·鲁本博士、血液病理学博士和临床和实验乳腺放射肿瘤学博士温迪·伍德沃德之间建立的多学科合作。目标是1)检测无转移疾病患者的CTCs和DTC，评估这些细胞的干细胞特征，并将其与转归和原发肿瘤干细胞ALDH1染色相关联；2)检测接受新辅助化疗的患者的CTCs和原发肿瘤干细胞，并将这些措施与移植和培养的原始活检材料之间的治疗反应关联起来，以进行分子研究；3)确定β-catenin和Notch-1串扰的关键介质，并测试作为放射增敏剂对这些途径的抑制。在这些研究中，我们希望证明CTCs/DTCs是癌症干细胞的预后和预测性替代物，易于在单细胞水平上进行检测。这一方法可用于根据拟议的临床前研究，使用靶向致敏剂选择患者进行个体化治疗。

DESCRIPTION (provided by applicant): It has been suggested that the small fraction of tumor cells capable of initiating local or distant recurrence exhibit properties of stem cells, and that identification and molecular characterization of putative cancer stem cells will lead to better outcomes through targeted cancer stem cell therapies in appropriately selected patients. Clinical studies examining the predictive and prognostic significance of these cells have been limited by several factors, including variable methods for isolating single cells from tissues, the need for multiple markers to distinguish committed from undifferentiated cells, and the availability of fresh tissue from patients for study. Originating from the primary tumor, circulating tumor cells (in the blood) and disseminated tumor cells (in the bone marrow) are attractive cancer stem cell candidates, and practical clinical surrogates for cancer stem cell study because they exist as single cells, and can be quantified using available FDA approved technology. Therefore, we propose a translational strategy to examine primary, circulating, and disseminated tumor cells from breast cancer patients to test our central hypothesis that circulating and disseminated tumor cells present in the blood and bone marrow of non-metastatic breast cancer patients represent cancer stem cells which are precursors to distant metastases and potential targets for novel treatment. Our hypothesis is based on preliminary data from an ongoing IRB-approved clinical protocol that demonstrates disseminated tumor cells in the bone marrow of patients with non-metastatic breast cancer are positive for the expression of cancer stem cell markers of tumor initiating capacity; CD44+CD24- and aldehyde dehydrogenase-1 (ALDH1). Translational aims are based on three IRB protocols and tailored to the material collected, treatment approach, and patient population in each trial. The translational work represents an established multidisciplinary collaboration between Massimo Cristofanilli, MD Breast Medical Oncology, James Reuben, PhD, Hematopathology, and Wendy Woodward, MD-PhD, Clinical and Experimental Breast Radiation Oncology. The goals are 1) Measure CTCs and DTCs in patients without metastatic disease, assess these cells for stem cell features and correlate these to outcome and ALDH1 staining in the primary; 2) Measure CTCs and primary tumor stem cells in patients receiving neoadjuvant chemotherapy and correlate response to therapy between these measures as well as transplant and culture primary biopsy material for molecular studies; 3) Determine key mediators of ¿-catenin and Notch-1 crosstalk in radioresistance of cancer stem cells, and test inhibition of these pathways as radiosensitizers. In these studies we hope to demonstrate that CTCs/DTCs are prognostic and predictive surrogates for cancer stem cells that are easily accessible for examination on the single cell level. This approach could be used to select patients for individualized therapy using targeted sensitizing agents based on the proposed preclinical studies.