Robu Adrian C, Vukelić Željka, Schiopu Catalin, Capitan Florina, Zamfir Alina D
Mass Spectrometry Laboratory, National Institute for Research and Development in Electrochemistry and Condensed Matter, 300224 Timisoara, Romania; Faculty of Physics, West University of Timisoara, 300223 Timisoara, Romania.
Department of Chemistry and Biochemistry, Faculty of Medicine, University of Zagreb, 10000, Šalata, Zagreb, Croatia.
Anal Biochem. 2016 Sep 15;509:1-11. doi: 10.1016/j.ab.2016.06.005. Epub 2016 Jun 14.
We report here on the introduction of mass spectrometry (MS) for profiling of native gangliosides from an extracranial tumor. The analytical approach was based on a modern platform combining the superior sensitivity and reproducibility of fully automated chip-based nanoelectrospray ionization (nanoESI) with the high resolution and mass accuracy provided by a hybrid quadrupole time-of-flight (QTOF) instrument. The feasibility of the method for the analysis of gangliosides, which are much less expressed in extracranial tissues, was here tested using as the model substrate an adrenal neuroblastoma (NB) specimen located in the abdominal region of a 2-year-old infant. Under properly optimized conditions, MS profiling revealed information on at least 61 different gangliosides exhibiting heterogeneity of the glycan and lipid compositions. NB was found dominated by species bearing short-chain oligosaccharide cores with a reduced overall Neu5Ac content. By chip-nanoESI MS, preceding findings related to the GD2 role in NB were confirmed. Moreover, the screening experiments offered novel information supporting the possible biomarker role of GM4, GM3, and GM1 ganglioside classes. Structural analysis of GM1(d18:1/18:2) and GD1(d18:0/19:0) possibly tumor-associated markers, carried out by tandem MS (MS/MS) using collision-induced dissociation (CID) at low energies, indicated that both GM1a and GD1b isomers are present in NB.
我们在此报告将质谱法（MS）用于分析颅外肿瘤中天然神经节苷脂的情况。该分析方法基于一个现代平台，它将全自动芯片基纳喷电喷雾电离（nanoESI）的卓越灵敏度和重现性与混合四极杆飞行时间（QTOF）仪器提供的高分辨率和质量精度相结合。本研究以一名2岁婴儿腹部区域的肾上腺神经母细胞瘤（NB）标本作为模型底物，测试了该方法用于分析在颅外组织中表达量低得多的神经节苷脂的可行性。在适当优化的条件下，质谱分析揭示了至少61种不同神经节苷脂的信息，这些神经节苷脂在聚糖和脂质组成上表现出异质性。发现NB主要由带有短链寡糖核心且总唾液酸（Neu5Ac）含量降低的种类组成。通过芯片纳喷电喷雾电离质谱法，先前关于GD2在NB中的作用的发现得到了证实。此外，筛选实验提供了新信息，支持GM4、GM3和GM1神经节苷脂类可能作为生物标志物的作用。通过在低能量下使用碰撞诱导解离（CID）的串联质谱（MS/MS）对可能与肿瘤相关的标志物GM1（d18:1/18:2）和GD1（d18:0/19:0）进行结构分析，表明NB中同时存在GM1a和GD1b异构体。
