Fig. 6.

FOXP3 acts as a co-activator of Wnt/β-catenin signaling in NSCLC cells. a Co-immunoprecipitation showed the physical interaction between FOXP3 and TCF4 in HEK-293 cells co-expressing Myc-TCF4 and FOXP3 or Flag-FOXP3 and TCF4. b Co-immunoprecipitation showed the physical interaction between FOXP3 and β-catenin in HEK-293 cells co-expressing Flag-β-catenin and FOXP3 or Myc-FOXP3 and β-catenin. c FOXP3 enhances the interaction of β-catenin and TCF4. Plasmids of Myc-TCF4, Flag-β-catenin and FOXP3 were co-transfected into HEK293T cells according to the situations indicated above. EGFP plasmids was co-transfected as the control of transfection efficiency. The cell lysates were subjected to IP with an anti-Flag antibody. The immunoprecipitates and the nuclear proteins were subjected to Western blots using the indicated antibodies. Lamin B1 was used to be the loading control of the nuclear protein. d FOXP3 enhances the interaction of endogenous TCF4 and β-catenin. A549 cells were infected with FOXP3 lentivirus or control lentivirus as indicated above for 48 h. The nuclear fractions were incubated with an anti-TCF4 antibody for the IP experiment. IgG was used as a negative control. The immunoprecipitates and the nuclear extracts were subjected to Western blots using the indicated antibodies. Lamin B1 was used to be the loading control of the nuclear protein