Lee Jua, Hua Serenus, Lee Sung Hyeon, Oh Myung Jin, Yun Jaekyung, Kim Jin Young, Kim Jae-Han, Kim Jung Hoe, An Hyun Joo
Asia Glycomics Reference Site, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon, 305-764, Republic of Korea.
Graduate School of Analytical Science and Technology, #455 College of Engineering II, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon, 305-764, Republic of Korea.
Anal Bioanal Chem. 2018 Feb;410(6):1617-1629. doi: 10.1007/s00216-017-0811-y. Epub 2017 Dec 29.
Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide, largely because of difficulties in early diagnosis. Despite accumulating evidence indicating that aberrant glycosylation is associated with GC, site-specific localization of the glycosylation to increase specificity and sensitivity for clinical use is still an analytical challenge. Here, we created an analytical platform with a targeted glycoproteomic approach for GC biomarker discovery. Unlike the conventional glycomic approach with untargeted mass spectrometric profiling of released glycan, our platform is characterized by three key features: it is a target-protein-specific, glycosylation-site-specific, and structure-specific platform with a one-shot enzyme reaction. Serum haptoglobin enriched by immunoaffinity chromatography was subjected to multispecific proteolysis to generate site-specific glycopeptides and to investigate the macroheterogeneity and microheterogeneity. Glycopeptides were identified and quantified by nano liquid chromatography-mass spectrometry and nano liquid chromatography-tandem mass spectrometry. Ninety-six glycopeptides, each corresponding to a unique glycan/glycosite pairing, were tracked across all cancer and control samples. Differences in abundance between the two groups were marked by particularly high magnitudes. Three glycopeptides exhibited exceptionally high control-to-cancer fold changes along with receiver operating characteristic curve areas of 1.0, indicating perfect discrimination between the two groups. From the results taken together, our platform, which provides biological information as well as high sensitivity and reproducibility, may be useful for GC biomarker discovery. Graphical abstract ᅟ.
胃癌（GC）是全球癌症相关死亡的主要原因之一，主要是由于早期诊断存在困难。尽管越来越多的证据表明异常糖基化与胃癌有关，但糖基化的位点特异性定位以提高临床应用的特异性和敏感性仍然是一个分析挑战。在这里，我们创建了一个具有靶向糖蛋白质组学方法的分析平台，用于发现胃癌生物标志物。与传统的糖组学方法不同，传统方法是对释放的聚糖进行非靶向质谱分析，我们的平台具有三个关键特征：它是一个具有单次酶反应的靶蛋白特异性、糖基化位点特异性和结构特异性平台。通过免疫亲和色谱富集的血清触珠蛋白进行多特异性蛋白水解，以生成位点特异性糖肽，并研究宏观异质性和微观异质性。通过纳升液相色谱-质谱和纳升液相色谱-串联质谱对糖肽进行鉴定和定量。在所有癌症和对照样品中跟踪了96种糖肽，每种糖肽对应于独特的聚糖/糖基化位点配对。两组之间丰度的差异表现为特别高的幅度。三种糖肽表现出极高的对照与癌症倍数变化，同时受试者工作特征曲线面积为1.0，表明两组之间有完美的区分。综合这些结果，我们的平台提供了生物学信息以及高灵敏度和可重复性，可能有助于发现胃癌生物标志物。图形摘要ᅟ。
