Background Cancer stem cells (CSCs) are reported to be responsible for tumor initiation, progression, metastasis, and therapy resistance where P-glycoprotein (P-gp) as well as other glycoproteins are involved. Identification of these glycoprotein markers is critical for understanding the resistance mechanism and developing therapeutics. Methods In this study, we report our comparative and quantitative site- and structure-specific N-glycoproteomics study of MCF-7/ADR cancer stem cells (CSCs) vs. MCF-7/ADR cells. With zic-HILIC enrichment, isotopic diethyl labeling, RPLC-MS/MS (HCD) analysis and GPSeeker DB search, differentially expressed N-glycosylation was quantitatively characterized at the intact N-glycopeptide level. Results 4016 intact N-glycopeptides were identified with spectrum-level FDR ≤ 1%. With the criteria of ≥ 1.5 fold change and p value < 0.05, 247 intact N-glycopeptides were found differentially expressed in MCF-7/ADR CSCs as putative markers. Raw data are available via ProteomeXchange with identifier PXD013836. Conclusions Quantitative site- and structure-specific N-glycoproteomics characterization may help illustrate the cell stemness property.

中文翻译：

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MCF-7/ADR 癌症干细胞中差异 N-糖基化的定量位点和结构特异性 N-糖蛋白质组学表征。

背景 据报道，癌症干细胞 (CSC) 与 P-糖蛋白 (P-gp) 以及其他糖蛋白相关的肿瘤发生、进展、转移和治疗抗性有关。这些糖蛋白标志物的鉴定对于了解耐药机制和开发治疗方法至关重要。方法 在本研究中，我们报告了 MCF-7/ADR 癌症干细胞 (CSC) 与 MCF-7/ADR 细胞的比较和定量位点和结构特异性 N-糖蛋白质组学研究。通过 zic-HILIC 富集、同位素二乙基标记、RPLC-MS/MS (HCD) 分析和 GPSeeker DB 搜索，在完整的 N-糖肽水平上定量表征了差异表达的 N-糖基化。结果 4016 个完整的 N-糖肽被鉴定为光谱水平 FDR ≤ 1%。符合≥1的标准。5 倍变化和 p 值 < 0.05，发现 247 个完整的 N-糖肽在 MCF-7/ADR CSCs 中差异表达，作为推定的标记。原始数据可通过 ProteomeXchange 获得，标识符为 PXD013836。结论 定量位点和结构特异性 N-糖蛋白组学表征可能有助于说明细胞干性特性。