Department of Chemistry, University of California, Davis, 95616, USA.
Analyst. 2011 Sep 21;136(18):3663-71. doi: 10.1039/c1an15093f. Epub 2011 Jul 21.
Glycosylation is highly sensitive to the biochemical environment and has been implicated in many diseases including cancer. Glycan compositional profiling of human serum with mass spectrometry has already identified potential biomarkers for several types of cancer and diseases; however, composition alone does not fully describe glycan stereo- and regioisomeric diversity. The vast structural heterogeneity of glycans presents a formidable analytical challenge. We have developed a method to identify and quantify isomeric native glycans using nanoflow liquid chromatography (nano-LC)/mass spectrometry. A microfluidic chip packed with graphitized carbon was used to chromatographically separate the glycans. To determine the utility of this method for structure-specific biomarker discovery, we analyzed serum samples from two groups of prostate cancer patients with different prognoses. More than 300 N-glycan species (including isomeric structures) were identified, corresponding to over 100 N-glycan compositions. Statistical tests established significant differences in glycan abundances between patient groups. This method provides comprehensive, selective, and quantitative glycan profiling.
糖基化对生化环境高度敏感，并与包括癌症在内的许多疾病有关。利用质谱对人血清中的聚糖组成进行分析已经鉴定出了几种癌症和疾病的潜在生物标志物；然而，仅组成并不能完全描述聚糖的立体和区域异构多样性。聚糖的巨大结构异质性带来了巨大的分析挑战。我们开发了一种使用纳流液相色谱（nano-LC）/质谱来鉴定和定量异构天然聚糖的方法。使用带有石墨化碳的微流控芯片进行色谱分离聚糖。为了确定该方法在结构特异性生物标志物发现中的实用性，我们分析了来自两组具有不同预后的前列腺癌患者的血清样本。鉴定出了 300 多种 N-聚糖种类（包括异构结构），对应于 100 多种 N-聚糖组成。统计检验确定了患者组之间聚糖丰度的显著差异。该方法提供了全面、选择性和定量的聚糖分析。
