Hall M Kristen, Whitman Austin A, Weidner Douglas A, Schwalbe Ruth A
Department of Biochemistry and Molecular Biology Brody School of Medicine, East Carolina University Greenville, Greenville, NC 27834, USA.
Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University Greenville, Greenville, NC 27834, USA.
Biology (Basel). 2020 Apr 4;9(4):71. doi: 10.3390/biology9040071.
Neuroblastoma (NB) development and progression are accompanied by changes in N-glycans attached to proteins. Here, we investigated the role of N-acetylglucosaminyltransferase-II (GnTII, ) protein substrates in neuroblastoma (NB) cells. was silenced in human BE(2)-C NB (HuNB) cells to generate a novel cell line, HuNB(-), lacking complex type N-glycans, as in rat B35 NB cells. Changes in N-glycan types were confirmed by lectin binding assays in both cell lines, and the rescued cell line, HuNB(-/+). Western blotting of cells heterologously expressing a voltage-gated K+ channel (Kv3.1b) showed that some hybrid N-glycans of Kv3.1b could be processed to complex type in HuNB(-/+) cells. In comparing HuNB and HuNB(-) cells, decreased complex N-glycans reduced anchorage-independent cell growth, cell proliferation, and cell invasiveness, while they enhanced cell-cell interactions. Cell proliferation, invasiveness and adhesion of the HuNB(-/+) cells were more like the HuNB than HuNB(-). Western blotting revealed lower protein levels of MMP-2, EGFR and Gab2 in glycosylation mutant cells relative to parental cells. Gelatin zymography demonstrated that decreased MMP-2 protein activity was related to lowered MMP-2 protein levels. Thus, our results support that decreased complex type N-glycans suppress cell proliferation and cell invasiveness in both NB cell lines via remodeling ECM.
神经母细胞瘤(NB)的发生和发展伴随着蛋白质上N-聚糖的变化。在此,我们研究了N-乙酰葡糖胺基转移酶-II(GnTII)蛋白底物在神经母细胞瘤(NB)细胞中的作用。在人BE(2)-C NB(HuNB)细胞中使GnTII沉默,以产生一种新型细胞系HuNB(-),该细胞系缺乏复杂型N-聚糖,如同大鼠B35 NB细胞一样。通过凝集素结合试验在两种细胞系以及拯救细胞系HuNB(-/+)中证实了N-聚糖类型的变化。对异源表达电压门控钾通道(Kv3.1b)的细胞进行蛋白质印迹分析表明,Kv3.1b的一些杂合N-聚糖在HuNB(-/+)细胞中可加工成复杂型。在比较HuNB和HuNB(-)细胞时,复杂N-聚糖的减少降低了非锚定依赖性细胞生长、细胞增殖和细胞侵袭性,同时增强了细胞间相互作用。HuNB(-/+)细胞的细胞增殖、侵袭性和黏附性更类似于HuNB而非HuNB(-)。蛋白质印迹显示,相对于亲本细胞,糖基化突变细胞中MMP-2、EGFR和Gab2的蛋白质水平较低。明胶酶谱分析表明,MMP-2蛋白活性的降低与MMP-2蛋白水平的降低有关。因此,我们的结果支持,复杂型N-聚糖的减少通过重塑细胞外基质抑制了两种NB细胞系中的细胞增殖和细胞侵袭性。