Fig. 2: FOXP4 is a transcriptional target for the Wnt/β-catenin/TCF4 signaling.

A The spearman correlation between the expression of FOXP4 and the HALLMARK_WNT_BETA_CATENIN_SIGNALING in all tumor types in TCGA. Red represents positive expression and green represents negative expression. B The mRNA correlation between FOXP4 and CTNNB1 in OV from TCGA database. C The mRNA correlation between FOXP4 and TCF4 in OV from TCGA database. D The mRNA correlation between FOXP4 and CCND1 in OV from TCGA database. E The mRNA expression levels of FOXP4, FOXP1 and three known downstream target genes of Wnt/β-catenin (CCND1, GSK3B, and c-Myc) in A2780 cells treated with DMSO or LiCl were determined by real-time PCR, n = 3. **p < 0.01 vs DMSO, ***p < 0.001 vs DMSO. F Immunoblot analysis was used to detect the protein expression levels of FOXP4 and three known Wnt/β-catenin downstream target genes CCND1, GSK3B, and c-Myc in A2780 cells treated with DMSO or LiCl. G Real-time PCR was used to measure mRNA levels of β-catenin, CCND1, and FOXP4 after transfection with EV or CTNNB1 in A2780 cells, n = 3. **p < 0.01 vs EV, ***p < 0.001 vs EV. H Immunoblot analysis was conducted to assess the protein expression of β-catenin, CCND1, and FOXP4 in A2780 cells following transfection with EV or β-catenin. I Real-time PCR was used to quantify mRNA levels of CCND1 and FOXP4 in OVCAR8 cells treated with either DMSO or ICG-001, n = 3. ***p < 0.001 vs DMSO. J Immunoblot analysis was used to determine the protein expression levels of CCND1 and FOXP4 in OVCAR8 cells after treatment with either DMSO or ICG-001. K Real-time PCR was utilized to quantify the mRNA expression of CTNNB1 and FOXP4 in OVCAR8 cells transfected with Con-shRNA or CTNNB1-shRNA, n = 3. **p < 0.01 vs Con-shRNA, ***p < 0.001 vs Con-shRNA. L Immunoblot analysis was conducted to determine the protein levels of β-catenin and FOXP4 in OVCAR8 cells transfected with Con-shRNA or CTNNB1-shRNA. M Schematic diam shows human FOXP4 gene promoter and two putative TCF4 binding sites. TSS: transcription start site. N The human FOXP4 promoter contains two TCF4 response elements. Point mutation was highlighted with black cross. O TCF4 was co-transfected with indicated plasmids into 293T cells for 36 h. The luciferase activity was then measured, n = 3. ***p < 0.001 vs Con. P, Q. A2780 cells stably expressing TCF4 were subjected to Chip-PCR detection, the human GAPDH promoter served as a negative control, n = 3. ***p < 0.001 vs IgG.