Department of Cell Biology, Van Andel Institute, 333 Bostwick Ave NE, Grand Rapids, MI, USA.
Mass Spectrometry Core, Van Andel Institute, 333 Bostwick Ave NE, Grand Rapids, MI, USA.
Commun Biol. 2024 Nov 26;7(1):1576. doi: 10.1038/s42003-024-07277-0.
Cell membrane glycans contribute to immune recognition, signaling, and cellular adhesion and migration, and altered membrane glycosylation is a feature of cancer cells that contributes to cancer progression. The uptake and metabolism of glucose and other nutrients essential for glycan synthesis could underlie altered membrane glycosylation, but the relationship between shifts in nutrient metabolism and the effects on glycans have not been directly examined. We developed a method that combines stable isotope tracing with metabolomics to enable direct observations of glucose allocation to nucleotide sugars and cell-membrane glycans. We compared the glucose allocation to membrane glycans of two pancreatic cancer cell lines that are genetically identical but have differing energy requirements. The 8988-S cells had higher glucose allocation to membrane glycans and intracellular pathways relating to glycan synthesis, but the 8988-T cells had higher glucose uptake and commitment of glucose to non-glycosylation pathways. The cell lines differed in the requirements of glucose for energy production, resulting in differences in glucose bioavailability for glycan synthesis. The workflow demonstrated here enables studies on the effects of metabolic shifts on the commitment of nutrients to cell-membrane glycans. The results suggest that cell-membrane glycans are remodeled through shifts in glucose commitment to non-glycosylation pathways.
细胞膜糖基化在免疫识别、信号转导和细胞黏附和迁移中发挥作用，癌细胞的膜糖基化改变是促进癌症进展的一个特征。葡萄糖和其他糖基化合成所需营养物质的摄取和代谢可能是膜糖基化改变的基础，但营养物质代谢的变化与糖基化的影响之间的关系尚未被直接研究。我们开发了一种将稳定同位素示踪与代谢组学相结合的方法，能够直接观察葡萄糖在核苷酸糖和细胞膜糖之间的分配。我们比较了两种遗传上相同但能量需求不同的胰腺癌细胞系的细胞膜糖基化的葡萄糖分配情况。8988-S 细胞具有更高的葡萄糖分配给细胞膜糖和与糖基合成有关的细胞内途径，但 8988-T 细胞具有更高的葡萄糖摄取和葡萄糖向非糖基化途径的分配。细胞系在葡萄糖产生能量方面的需求不同，导致糖基合成所需的葡萄糖生物利用度不同。这里展示的工作流程能够研究代谢变化对细胞外膜糖基化的营养物质分配的影响。结果表明，细胞膜糖基化通过葡萄糖向非糖基化途径的分配变化进行重塑。
