fig5

Figure 5. LINC01133 regulates cisplatin sensitivity and the Caspase-1/GSDMD pathway across different LUAD cell models. (A) Cisplatin dose–response curves of A549, A549/DDP, and PC9 cells determined using the CCK-8 assay, together with IC₅₀ values calculated by nonlinear regression; (B) Basal LINC01133 expression levels in A549, A549/DDP, and PC9 cells measured by qRT-PCR; (C) The relative expression level of LINC01133 in transfected PC9 cells was determined by qRT-PCR; (D) The effect of LINC01133 expression on the cisplatin sensitivity of PC9 cells was assessed using the CCK-8 assay. Cisplatin concentrations were set at 0.25, 0.5, 1, 2, 4, and 8 μg/mL, and IC₅₀ values were calculated from dose-response curves fitted by nonlinear regression; (E) The protein levels of cleaved Caspase-1 and GSDMD-NT in PC9 cells before and after cisplatin treatment were examined by Western blotting. Densitometric values of the target proteins were normalized to GAPDH and are presented as relative protein expression levels. Data were obtained from three independent biological replicates and are presented as the mean ± SD (n = 3); (F) The effects of LINC01133 expression on key pyroptosis-related proteins in PC9 cells were evaluated by Western blotting. Densitometric values of the target proteins were normalized to GAPDH and are presented as relative protein expression levels. Data were obtained from three independent biological replicates and are presented as the mean ± SD (n = 3); (G) Summary of cisplatin IC₅₀ values in the matched viral control and LINC01133-manipulated groups across different LUAD cell models. LINC01133 was overexpressed in A549 and PC9 cells and knocked down in A549/DDP cells. Comparisons were performed within each cellular background; (H) Western blotting and densitometric analysis of cleaved Caspase-1 and GSDMD-NT levels in A549, A549/DDP, and PC9 cells before and after cisplatin treatment; (I) Within-cell-model normalized changes in cleaved Caspase-1 and GSDMD-NT levels. The left panel shows cisplatin-induced changes, whereas the right panel shows the effects of LINC01133 manipulation. LINC01133 was overexpressed in A549 and PC9 cells and knocked down in A549/DDP cells. The dashed line represents a fold change of 1. A fold change greater than 1 indicates an increase in protein level relative to the corresponding matched control, whereas a fold change less than 1 indicates a decrease. Statistical comparisons among three groups were performed using one-way ANOVA followed by Tukey’s multiple-comparisons test, whereas comparisons between two groups were performed using a two-tailed unpaired Student’s t-test. ^*P < 0.05; ^**P < 0.01; ^***P < 0.001; ns: not significant. LUAD: Lung adenocarcinoma; DDP: cisplatin; CCK-8: Cell Counting Kit-8; IC₅₀: half-maximal inhibitory concentration; qRT-PCR: quantitative reverse transcription-polymerase chain reaction; SD: standard deviation; ANOVA: analysis of variance.