Fig 2: KLF4 upregulated BIK expression. a KLF4 WT or KO PC3 cells were treated with 20 μM cisplatin at the indicated times. Gene expression profiles were obtained by RNA sequencing analysis. b-e PC3 and DU145 cells with or without KLF4 KO were treated with 20 μM cisplatin at the indicated times. The mRNA and protein levels of BIK were analysed by q-RT-PCR and western blotting. Data represent the mean ± SD of three independent experiments. *** p < 0.001 vs. control. f-i PC3 and DU145 cells with or without KLF4 knockdown were treated with 20 μM cisplatin at the indicated times. The mRNA and protein levels of BIK were analysed by q-RT-PCR and western blotting. Data represent the mean ± SD of three independent experiments. ***p < 0.001 vs. control

Fig 3: miR-200b-3p targets KLF4 mediated autophagy inhibition to enhance 5-FU sensitivity in CCA cells. (A) Western blot analysis of LC3B and p62 expression in TFK-1 cells expressing NC or miR-200b-3p with or without KLF4 overexpression. (B) TFK-1 cells pre-transfected with GFP-mRFP-LC3B were transfected with NC or miR-200b-3p with or without KLF4 overexpression. Representative confocal images of autophagosome (yellow puncta) and autolysosome (red puncta) formation are presented in the left panel. Scale bar: 10 μm. The numbers of RFP+GFP+ LC3 puncta and RFP+GFP− LC3 puncta are presented in the right panel. **p < 0.01; ***p < 0.001. (C) TFK-1 cells stably expressing NC or shKLF4 in the absence or presence of EBSS treatment (24 h) were evaluated for cell sensitivity to 5-FU using the CCK8 assay upon exposure to step-up concentrations of 5-FU for 24 h. Dose-effect curves and statistical analysis of IC50 values are presented in the left and right panels, respectively. ***p < 0.001. (D) Flow cytometry detecting apoptotic cells in TFK-1 cells stably expressing NC or shKLF4 in the absence or presence of EBSS treatment (24 h) in the absence or presence of 40 μg/mL of 5-FU.

Fig 4: MiR-126 promoted macrophage phenotype to switch from M1 to M2 via VEGFA/KLF4 signaling.(A) PPI network generated with STRING website. (B) The miR-126-5p-VEGFA co-expression field from starBase. P = 0.0181. (C and F) Quantification of KLF4 and VEGFA mRNA levels. Four asterisks (****) denote P value < 0.0001, three asterisks (***) denote P value < 0.001, two asterisks (**) denote P value < 0.01, and one asterisk (*) denotes P value < 0.05 by one-way ANOVA analysis (n = 4, >1,000 cells per trial). (D and G) Western blots indicating total KLF4, VEGFA and β-Actin levels in whole cell lysates. (E and H) Quantification of KLF4 and VEGFA protein levels from (D and G). Three asterisks (***) denote P value < 0.001, two asterisks (**) denote P value < 0.01, and one asterisk (*) denotes P value < 0.05 by one-way ANOVA analysis (n = 4, >1,000 cells per trial).

Fig 5: Schematic diagram of the mechanism by which SNHG1 promotes the adaptation to ER stress. SNHG1 is a KLF4‐regulated lncRNA that suppresses ER stress‐induced apoptosis and facilitates gliomagenesis by elevating BIRC3 expression.