Journal: iScience
Article Title: Multilevel plasticity and altered glycosylation drive aggressiveness in hypoxic and glucose-deprived bladder cancer cells
doi: 10.1016/j.isci.2025.111758
Figure Lengend Snippet: Hypoxia and low glucose impair O -glycans extension in BLCA, originating a simple cancer cell glycophenotype (A) BLCA cells exposed to hypoxia and low glucose exhibit less abundant, simpler, and shorter glycomes, lacking extensions beyond core 1 structures. nanoLC-MS/MS analysis shows that this glycophenotype is characterized by sialylated T antigens and core 3, likely due to decreased typical core 1 and 2 structures. DFX-treated cells, stabilizing HIF-1α, show no significant alterations in the glycome, suggesting that changes observed in stressed cells are not driven by HIF-1α. (B) Lectin affinity studies show significant upregulation of Tn and sialylated T antigens (recognized by PNA lectin after Neuraminidase [NeuAse] digestion) under stress, in accordance with MS-based glycomics. Notably, core 3 O -glycans (evaluated by GSL II lectin after PNGase F digestion) remain unchanged, highlighting that cellular stress primarily suppresses core 1/2 O -glycans, rather than increasing core 3 O -glycans. (C) Glucose suppression is the primary driver of glycome remodeling, which can be reversed by reoxygenation and restoration of glucose. (D) Glycogene remodeling is primarily driven by the combined effects of hypoxia and glucose deprivation and leads to a premature halt in glycans extension beyond core 1. C1GALT1C1 , necessary for core 1 biosynthesis, is downregulated, whereas ST3GAL1 , 3 , and 4 are overexpressed, increasing sialylated T antigens and inhibiting core 2 formation. Downregulation of GCNT4 also contributes to core 2 inhibition. Interestingly, elevated GCNT1 and GCNT3 potentially counterbalance core 2 suppression. (E) Quantification of key enzymes involved in O -glycan elongation (C1GalT1; Cosmc; BGnT-6; C2GNT; ST3Gal-I) shows significant upregulation of ST3Gal-1 in stressed cells, consistent with transcriptomics. The others remain unchanged, indicating distinct regulation between glycogenes and glycosyltransferases under these conditions. Bold circles and triangles represent statistically significant changes in T24 and 5637 cell lines, respectively. Error bars represent mean ± SD for three independent experiments. Mann-Whitney Test was used for statistical analysis. Results were considered statistically significant when p < 0.05.
Article Snippet: Griffonia (Bandeiraea) Simplicifolia Lectin II (GSL II, BSL II), Fluorescein , Vector Laboratories , FL-1211-2.
Techniques: Tandem Mass Spectroscopy, Inhibition, MANN-WHITNEY