Figure 8

FOXO1 represses Wnt/β-catenin signaling. MG-63 and U2-OS cells expressing FOXO1ER or empty vector were treated with 100 nM 4-OHT or vehicle. (a) One day later, cells were co-transfected with TOPflash luciferase construct and Renilla luciferase vector; the luciferase activity was measured 24 h after transfecting. All experiments were carried out in triplicate. The data represent mean±s.d. of least three experiments. (b, c) Two hours (data not shown) or 24 h later, cells were fixed and immunostained with FOXO1 (red) and β-catenin (green) antibodies and visualized under a microscope. 4-OHT induced FOXO1 translocation from the cytoplasm to the nucleus in MG-63 FOXO1ER cells (b) and U2-OS FOXOER cells (c), and decreased the expression of β-catenin with no influence on the intracellular localization of β-catenin. The experiment was repeated three times with similar observations.