Ependymomas are the third most common brain tumor in children and are characterized by a high probability of relapse (>50%) and poor survival rate (<50%). The availability of pediatric ependymoma tissue for analysis is however scarce and small in size (<1 mm) limiting extensive metabolomics analysis into brain tumor metabolism using standard techniques such as gas or liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy. Here, we present a novel serial surface mass spectrometry-based strategy for metabolite profiling of pediatric ependymoma tissue microarrays (TMA) using Orbitrap secondary ion mass spectrometry (3D OrbiSIMS), followed by liquid extraction surface analysis-tandem MS (LESA-MS/MS). The use of this strategy permitted a broader coverage of metabolites and allowed identification of putative metabolites for accurate prediction of ependymoma relapse. This strategy opens new opportunities to retrospectively link molecular data from any formalin-fixed paraffin-embedded (FFPE) TMA library with clinical outcomes.

中文翻译：

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顺序3D OrbiSIMS和基于LESA-MS / MS的代谢组学可从样品有限的主要组织档案中预测脑肿瘤的复发

室间隔膜瘤是儿童中第三大最常见的脑肿瘤，其特征是复发的可能性高（> 50％），生存率低（<50％）。然而，用于分析的儿科室膜膜瘤组织稀缺且尺寸小（<1 mm），限制了使用标准技术（例如气相色谱或液相色谱-质谱法和核磁共振波谱法）将广泛的代谢组学分析应用于脑肿瘤代谢。在这里，我们介绍一种基于串行表面质谱的新型策略，用于使用Orbitrap二次离子质谱仪（3D OrbiSIMS）对小儿室管膜瘤组织微阵列（TMA）进行代谢物分析，然后进行液相萃取串联质谱（LESA-MS / MS） ）。该策略的使用允许更广泛的代谢物覆盖范围，并允许鉴定假定的代谢物以准确预测室间隔膜瘤的复发。该策略为将任何福尔马林固定石蜡包埋（FFPE）TMA库中的分子数据与临床结果进行回顾性链接提供了新的机会。