Fig. 6

β-CATENIN regulates the transcription of IL8. A Immunoblot assessment of the total and nuclear levels of β-CATENIN in the matched mammosphere-enriched BCSCs and parental MCF-7 or T47D cells. B The correlation of CTNNB1 and IL8 was analyzed in TCGA breast cancer dataset. C Immunoblot assessment of the total and nuclear levels of β-CATENIN or IL8 in MCF-7 or T47D cells transfected with two different shRNAs to β-CATENIN. D Immunoblot assessment of the protein levels of β-CATENIN or IL8 in MCF-7 cells treated with CHIR99021 or XAV939. E Schematic representation of the predicted TCF4 binding sites in the promoter region of IL8 based on rVista 2.0 software. F The ChIP-sequencing data shows the enrichments of TCF4 around the promoter region of IL8 were analyzed in the GEO database (GSM782123 and GSM816437). G The regulation of wild-type or TCF4 binding site mutant IL8 promoter activities by β-CATENIN were determined by luciferase reporter assay. The luciferase reporter activities in the transfected MCF-7 cells were determined with Renilla luciferase activity as input control. H ChIP assay analysis of the enrichment of TCF4 to the IL8 promoter region in MCF-7 cells. I ChIP assay analysis of the enrichment of β-CATENIN to the IL8 promoter region in BCSCs or parental MCF-7 cells. All experiments were repeated at least three times. Results are shown as mean ± S.D. *P < 0.05; **P < 0.01; ***P < 0.001; ns, not significant (One-way ANOVA followed by Tukey’s multiple comparison test)