血清免疫球蛋白GN-糖基的高通量分析——一种消化道癌症的非侵入性生物标志物

High-Throughput Profiling of Serological Immunoglobulin G N-Glycome as a Noninvasive Biomarker of Gastrointestinal Cancers

免疫球蛋白G(Immunoglobulin G,IgG)的N-糖基化在炎症性疾病的发展中起着重要作用。本研究旨在评价IgG N-糖基在消化道癌症亚型中的诊断效能。从中国医学科学院肿瘤医院招募749名消化道癌症患者,包括食管癌(esophageal cancer,EC)、胃癌(gastric cancer,GC)、结直肠癌(colorectal cancer,CRC)和胰腺癌(pancreatic cancer,PC)患者。采用亲水交互高效液相色谱-超高效液相色谱(hydrophilic interaction liquid chromatography using ultra-performance liquid chromatography,HILIC-UPLC)分析血浆中IgG的N-糖基构成。采用Bio-Plex悬液芯片系统检测方法(Bio-Rad)进行炎症因子检测。采用典型相关分析(canonical correlation analysis,CCA)探索糖基和炎症因子之间的相关性。采用LASSO回归和logistic回归模型,基于检测到的糖基谱建立可用于区分胃肠癌症患者和健康人群诊断模型。与健康对照组相比,EC、GC、CRC和PC患者的唾液酸化和半乳糖基化水平降低,而二等分乙酰葡萄糖胺基化水平在消化道癌症患者中升高。此外,只有胰腺癌患者具有低水平的岩藻糖基化。消化道癌症组的IL-1β、IL-31和sCD40L水平均高于对照组。IgG N-糖基的组成与炎症因子相关(r=0.556)。基于糖基的模型表现出良好的诊断效能,EC、GC、CRC和PC的受试者工作特征曲线下面积(AUC)分别为0.972、0.871、0.867和0.907。这些研究结果表明,IgG N-糖基在调节消化道肿瘤的发病机制中发挥了重要作用。血清IgG N-糖基可以作为潜在的非侵入性辅助消化道癌症临床诊断的方法。

Immunoglobulin G(IgG)N-glycosylation plays a crucial role in the development of inflammatory diseases.This study aimed to evaluate the diagnostic performance of IgG for gastrointestinal(GI)cancer subtypes.A total of 749 GI cancer patients were enrolled from the Cancer Hospital,Chinese Academy of Medical Sciences,including esophageal cancer(EC),gastric cancer(GC),colorectal cancer(CRC),and pancreatic cancer(PC)patients.Hydrophilic interaction liquid chromatography using ultra-performance liquid chromatography(HILIC-UPLC)was employed to analyze the composition of the plasma IgG Nglycome.The levels of circulating inflammatory cytokines were detected by means of a Bio-Plex Pro Human Th17 Cytokine Assay.Canonical correlation analysis(CCA)was used to explore the correlation between IgG N-glycosylation patterns and inflammatory cytokines.A Lasso algorithm,accompanied by a logistic regression model,was used to develop a glycan-based model for differentiating GI cancer patients from healthy individuals.The levels of sialylation and galactosylation were significantly decreased among EC,GC,CRC,and PC patients,whereas the abundance of glycans with bisecting Nacetylglucosamine(GlcNAc)was increased in GI cancer patients in comparison with the healthy controls.Moreover,only PC patients had a decreased level of fucosylation.The levels of interleukin 1b(IL-1b),IL31,and soluble CD40 ligand(sCD40L)were significantly higher in GI cancer patients than in the controls.In addition,the composition of IgG N-glycans was correlated with that of inflammatory cytokines(r=0.556).The glycan-based models for diagnosing GI cancers exhibited an excellent performance,with areas under the receiver operating characteristic curves(AUCs)of 0.972 for EC,0.871 for GC,0.867 for CRC,and 0.907 for PC.Our findings demonstrate that IgG N-glycosylation plays an important role in modulating the pathogenesis of GI cancers.Serological IgG N-glycosylation is thus a potential candidate for noninvasively assisting in the clinical diagnosis of GI cancer subtypes.