Figure 1 from Oncogenic Mutant p53 Sensitizes Non–Small Cell Lung Cancer Cells to Proteasome Inhibition via Oxidative Stress–Dependent Induction of Mitochondrial Apoptosis
Year: 2024
Type: other
Abstract: Onc-p53 regulates basal levels of 20S proteasome activity and is required for BTZ-induced cytotoxicity in NSCLC cells. A, 20S proteasome activity was determined in the indicated cell lines using a fluorometric proteosome activity assay and plotted as mean fluorescence units (MFU). All pairwise comparisons were made using the Student t test. B, (Left) Relative 20S proteasome activity in lysates of H1975-Control vs. H1975-p53KO cells. (Right) Cell lysates of H1975-Control and H1975-p53KO (p53KO) cell lines generated using CRISPR/Cas9 were immunoblotted with p53 and GAPDH antibodies. C, The indicated cells were treated with vehicle or increasing concentrations of BTZ (left) or CFZ (right) for 72 hours, and cell viability was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. A paired t test was performed to analyze differences in viability among the cell lines. D, (Left) H1975-Control or H1975-p53KO cells expressing GFP or p53R273H were treated with BTZ (5 nmol/L) for 48 hours, and cell viability was determined by trypan blue exclusion assay. (Right) Lysates of the indicated cell lines were immunoblotted with p53 and GAPDH antibodies. E, (Left) H460 or H460-p53KO (18) cells were treated with vehicle (−) or BTZ (5 nmol/L) for 72 hours, and cell viability was determined by WST-1 assay. (Right) Cell lysates of H460 and H460-p53KO cells were immunoblotted with p53 and GAPDH antibodies. F, (Left) H460-p53KO cells stably expressing GFP or p53R273H were treated with increasing concentrations of BTZ for 72 hours, and cell viability was determined by WST-1 assay. (Right) Cell lysates of H460-p53KO cells stably expressing GFP or p53R273H were immunoblotted with p53 and GAPDH antibodies. *, P < 0.05; **, P < 0.01; ***, P < 0.005; ns, P > 0.05. Error bars indicate ± 1.0 SD.
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
OpenAlex ID: W4403433633