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 shift BLCA cell metabolism from glycolytic to lipolytic, increasing lipid droplet formation and reducing the number of active mitochondria (A–C) PLS-DA analysis reveals similar metabolic responses in 5637 and T24 cells under microenvironmental stress (A). Volcano plot highlights significant metabolome alterations in response to hypoxia and low glucose (B). Downregulated metabolites include UDP-Glc, UDP-GalNAc, gluconic acid, and citric acid, whereas increased metabolites indicate active fatty acid transport and β-oxidation (C). Significant reduction in key metabolites linked to nucleotide, amino acids, Krebs cycle, and lipid metabolism was observed, consistent with catabolic metabolism. An exception is the accumulation of long fatty acid acylcarnitine for transfer across the inner mitochondrial membrane for β-oxidation. (D) Pathway enrichment analysis supports fatty acid β-oxidation as the primary bioenergetic pathway in stressed cells. Key metabolic pathways, including carnitine biosynthesis and lysine/methionine degradation, contribute to fatty acid β-oxidation. (E) Hypoxia and low glucose induce lysine and methionine degradation to support acylcarnitine biosynthesis and lipid β-oxidation. (F) Joint pathway analysis incorporating transcriptomics and metabolomics studies supports changes from glycolytic to lipolytic metabolism, impacting nucleotides and sugars biosynthesis, including O -GalNAc glycans and protein O -glycosylation. (G and H) Hypoxia and low glucose increase AMP/ATP ratio (G) and activate AMPK by phosphorylation (H), indicating impaired oxidative phosphorylation and potential catabolic processes, including mitophagy. (I) Citrate synthase activity decreases under hypoxia and low glucose, suggesting a reduction in functional mitochondria. (J) TEM analysis reveals major morphological changes, including compromised mitochondria, lipid droplets, peridroplet mitochondria, membrane vesicles, and increased shedding of vesicles, indicating membrane activity changes under stress. 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: Human BLCA cell line RT4 (white male patient) , ATCC , HTB-2 TM.
Techniques: Membrane, Glycoproteomics, Phospho-proteomics, Activity Assay, Functional Assay, MANN-WHITNEY