Characterization of biomarkers on circulating tumor cells to guide therapy

描述(申请人提供)：乳腺癌相关死亡是由转移生长引起的并发症引起的。转移患者的治疗重点是延长生存期和控制症状，治疗的选择往往基于在原发乳腺肿瘤中发现的特定靶蛋白，这种肿瘤通常在发生转移疾病前数年切除。对这些靶蛋白的治疗在治疗转移性患者方面比标准化疗有效得多。由于癌症会随着时间的推移而变化，一些转移性肿瘤中的靶蛋白很可能已经从原发肿瘤中的水平发生了变化。可以检测转移组织中目标蛋白水平的活组织检查带来了问题，因为它们是侵入性的，对患者构成风险，而且对于有多个不同肿瘤部位的患者来说是不可行的。这项建议旨在定位血液中循环的肿瘤细胞，并测试它们的靶蛋白--帮助选择治疗方法的蛋白质。因为循环肿瘤细胞(CTCs)代表了当前的转移性疾病，可以说它们比原发肿瘤更能代表转移性疾病。循环中的肿瘤细胞很少见，也很难找到。目前用于发现CTC的技术存在问题。由于富集靶的低水平表达，一些人错过了某些类型的肿瘤细胞，并提供了糟糕的细胞图像，因此很难确定它们是CTC。其他技术依靠大小来寻找CTC，但大小差别很大，这样的技术错过了小型CTC。在这项工作中，一种名为快速细胞仪的研究仪器使用了一种已知在实体瘤细胞中高水平表达的富集靶。该分析不会降低细胞的形态，成像是在平面上进行的，以实现高保真。该提案涉及将研究仪器转变为经批准用于临床试验的仪器所需的工作。将开发监测仪器和多重分析的准确性的方法。将建立程序，以实现临床试验所需的CLIA认证。这项临床试验将集中在原发肿瘤三阴性的转移性乳腺癌患者身上。这种肿瘤类型的患者没有靶蛋白，没有资格接受靶向治疗。因此，他们面临的结果要糟糕得多。对3种靶蛋白进行多重检测的初步数据表明，CTC上的靶蛋白存在于相当数量的患者中。第二阶段的临床试验将确定当实施相关的靶向治疗时，这些患者是否存活更长时间。对CTCs使用靶蛋白水平的临床验证应该能够实现更有效和个性化的靶向治疗和预防获得性耐药，从而产生更好的反应、更好的无进展和更好的总体生存。 公共卫生相关性：转移性乳腺癌可以通过特殊疗法进行最佳治疗，这种疗法是根据原发乳癌中相关蛋白质的存在而选择的，原发乳癌通常在发生转移性疾病前数年切除。众所周知，癌症会随着时间的推移而变化，转移性肿瘤中的蛋白质很可能是不同的。这项建议旨在定位血液中循环的肿瘤细胞，并在临床试验中确定它们的蛋白质是否可以更好地指导治疗方法的选择。这项试验将专注于那些在原发肿瘤上没有特殊蛋白质的患者，因此面临更糟糕的结果。

DESCRIPTION (provided by applicant): Breast cancer-related death results from complications due to metastatic growth. Therapies for metastatic patients focus on extending survival and controlling symptoms, and the choice of therapies is frequently based on particular target-proteins found in the primary breast tumor, which is usually excised years before development of metastatic disease. Therapies for these target-proteins are much more effective in treating metastatic patients than standard chemotherapy. Because cancer changes over the time, the target-proteins in some metastatic tumors could well have changed from levels on the primary tumor. Biopsies that could test target proteins levels in metastatic tissue pose a problem because they are invasive, pose risk to the patient and are infeasible for patients with multiple different tumor sites. This proposal addresses locating tumor cells circulating in the blood and testing them for the target-proteins that help selection of a therapy. Because, circulating tumor cells (CTCs) represent the current metastatic disease, they arguably better represent metastatic disease than the primary tumor. Circulating tumor cells are rare and difficult to find. Current technologies used to find CTCs have problems. Some miss certain types of tumor cells due to low levels of expression of the enrichment target and provide poor images of the cells making it hard to be sure that they are CTCs. Others rely on size to find CTCs, but size varies widely, and such technologies miss small CTCs. In this work a research instrument, the FAST cytometer, uses an enrichment target that is known to be expressed at high levels in solid tumor cells. The assay does not degrade the cell morphology, and imaging is done on a planar surface for high fidelity. This proposal addresses the work needed to transform the research instrument into an instrument approved for use in a clinical trial. Methods will be developed to monitor the accuracy of the instrument and the multiplex assay. Procedures will be established to enable the CLIA certification needed for the clinical trial. The clinical trial will focus on metastatic breast cancer patients who have a triple negative primary tumor. Patients with this tumor type have no target-proteins and are ineligible to receive the targeted therapies. Consequently, they face a much poorer outcome. Preliminary data with a multiplex assay for 3 target-proteins has shown that target-proteins on CTCs are present in a significant number of patients. The clinical trial in Phase II will determine if these patients survive longer when the relevant target-therapies are administered. Clinical validation of the use of target protein levels on CTCs should enable more effective and personalized targeted therapy and prevention of acquired drug resistance, resulting in better response, improved progression-free and better overall survival. PUBLIC HEALTH RELEVANCE: Metastatic breast cancer can be optimally treated with special therapies that are selected by the presence of related proteins in the primary breast tumor, which is usually excised years before development of metastatic disease. As cancer is known to change over the time, the proteins in metastatic tumors could well be different. This proposal seeks to locate tumor cells circulating in the blood and determine in a clinical trial whether their proteins can better guide the selection of a therapy. The trial will focus on patients who have no special proteins on their primary tumors and hence face a worse outcome.