Molecular Diagnostics for Risk Stratification and Monitoring of Neuroblastoma

描述（由申请人提供）：尽管高危转移性神经母细胞瘤儿童的治疗在过去20年中有了显著改善，但这些患者中只有45%成为长期无病幸存者，骨髓是耐药或复发性疾病的常见部位。生存率的提高需要基于诊断时基于生物学的风险分层和对治疗反应的高度敏感监测，为患者提供有效的新疗法，以识别具有不同结果的患者亚组，这些患者目前在临床上无法区分。高风险神经母细胞瘤很少有复发性体细胞突变，这就排除了依赖于频繁改变的致癌驱动因素的分子分类和治疗。我们开发了一种新型的临床适用的TaqMan(R)低密度阵列（TLDA）基因表达测定法，用于诊断时的预测和量化这组患者骨髓和血液中的“肿瘤负荷”。总体目标：与儿童肿瘤小组（COG）合作，验证这些新的分子诊断的临床效用，然后将其建立为CAP/ clia认可的测试。具体目的：确认1)未经治疗的原发性MYCN非扩增神经母细胞瘤的预测标记（14基因TLDA测定）和2)用于量化骨髓和血液中“肿瘤负荷”的检测标记（5基因TLDA测定）的性能特征和临床效用。3)在影像学和临床变量的背景下，确定这些检测单独或联合是否能改善预后预测。研究设计和方法：将验证TLDA检测在神经母细胞瘤反应风险分层和监测方面的性能特点和临床应用，并将在CAP/ clia认可的实验室（包括洛杉矶儿童医院[CHLA]和全国儿童/COG生物病理学中心[BPC]）安装测试，以便将来用于临床决策。这些测试的分析性能特征将在CHLA和BPC实验室确认，临床应用研究将在CHLA进行。14个基因的预测签名预测了三个独立临床试验的结果，我们有信心使用来自四个COG研究的300个存档和前瞻性样本的其他研究将复制现有数据。5基因检测标记（CHGA、DCX、DDC、PHOX2B和TH）可以在106个正常骨髓或血细胞中识别出一个肿瘤细胞，初步研究表明，诱导、清骨髓巩固和巩固后治疗期间骨髓和PBSC中的肿瘤负荷与预后相关。这些结果将通过来自4个COG研究的2250个存档的和未来的骨髓、血液和PBSC样本进行验证。旨在优化分层和监测临床决策的综合分析将包括这些分子诊断测试、131i -间碘苄基胍（MIBG）成像和临床变量。总结：我们期望我们的分子诊断方法能够改善对高危转移性神经母细胞瘤患者预后的预测，并开发出更有效的治疗方法。

DESCRIPTION (provided by applicant): Although treatment for children with high-risk metastatic neuroblastoma has improved significantly in the past 20 years, only 45% of these patients become long-term, disease-free survivors, and bone marrow is a frequent site of resistant or recurrent disease. Improvement in survival necessitates effective new therapies for patients based upon biologically based risk stratification at diagnosis and highly sensitive monitoring of response to therapy that will identify patient subgroups with different outcomes who currently are clinically indistinguishable. High-risk neuroblastomas have few recurrent somatic mutations, which obviates molecular classification and therapies that rely on frequently altered oncogenic drivers. We have developed novel and clinically applicable TaqMan(R) Low Density Array (TLDA) gene expression assays for prognostication at diagnosis and for quantifying "tumor load" in bone marrow and blood for this group of patients. Overall goal: Validate the clinical utility of these new molecular diagnostics in collaboration with the Childrens Oncology Group (COG) and then establish them as CAP/CLIA-accredited tests. Specific Aims: Confirm performance characteristics and clinical utility 1) of a prediction signature (14-gene TLDA assay) for untreated primary MYCN non-amplified neuroblastomas and 2) of a detection signature (5-gene TLDA assay) for quantifying "tumor load" in bone marrow and blood. 3) Determine if these assays alone or combined improve prediction of outcome in the context of imaging and clinical variables. Research Design and Methods: The performance characteristics and clinical utility of the TLDA assays for risk stratification and monitoring of neuroblastoma response will be validated, and tests will be installed in CAP/CLIA-accredited laboratories including those at Children's Hospital Los Angeles [CHLA] and Nationwide Children's/COG Biopathology Center [BPC] so that they may be used in the future for clinical decision-making. Analytical performance characteristics of these tests will be confirmed in both CHLA and BPC laboratories, and clinical utility studies will be performed at CHLA. The 14-gene prediction signature predicted outcome in three independent clinical trials, and we are confident that additional studies using 300 archived and prospective samples from four COG studies will replicate existing data. Initial studies of the 5-gene detection signature (CHGA, DCX, DDC, PHOX2B, and TH), which can identify one tumor cell among 106 normal bone marrow or blood cells, showed that tumor load in bone marrow and PBSC during induction, after myeloablative consolidation, and after post-consolidation therapy correlates with outcome. These results will be validated with 2,250 archived and prospective bone marrow, blood, and PBSC specimens from four COG studies. Comprehensive analyses aimed at optimizing stratification and monitoring for clinical decision making will include these molecular diagnostic tests, 131I-meta-iodobenzyguanidine (MIBG) imaging, and clinical variables. Summary: We anticipate that our moelcular diagnostic assays will improve prediction of outcome and development of more effective therapy for patients with high-risk metastatic neuroblastoma.