CCAAT/Enhancer-Binding Protein Delta Regulates Glioblastoma Survival through Catalase-Mediated Hydrogen Peroxide Clearance

Figure 5

Overexpression of CAT decreases caspase 3/7 activity and ameliorates cell viability and mitochondrial function in CEBPD knockdown GBM cells. (a) The U373MG or T98G stable clones were transiently transfected with HA or HA-CAT for 24 h and then subjected to CCK-8 viability assay. (b) Stable knockdown clones of U373MG or T98G cells were transfected with HA or HA-CAT plasmids. After 24 h, cells were harvested and the caspase 3/7 activity was determined by Caspase-Glo® 3/7 reagent. (c) Stable knockdown clones of U373MG or T98G cells were transfected with HA or HA-CAT plasmids. After 24 h, cells were treated with or without H₂O₂ for 6 h and then harvested for the measurement of H₂O₂ levels. (d) The T98G cells were transiently cotransfected with control siRNA or CEBPD siRNA and HA or HA-CAT. After 72 h, cells were harvested and subjected to Seahorse XF Mito stress test to determine ATP-linked respiration. Bars represent the from three independent experiments. Differences among groups were determined with one-way or two-way ANOVA followed by Tukey’s multiple comparison test. and . ns: no significant; shLuc: shRNA for luciferase; shB7, shC7: shRNAs for CEBPD; siNeg: siRNA for negative control; si2896: siRNA for CEBPD; HA: hemagglutinin; HA-CAT: HA-tagged catalase.

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