Deguelin induces G2–M phase cell-cycle arrest and polyploidy in ESCC cells. (a) KYSE150 cells were treated with DMSO or deguelin (1, 2 or 5 μM) for 24 h, cells were collected and cell cycle was then analyzed using propidium iodide staining and flow cytometry. (b) Eca109 cells were treated with DMSO or deguelin (1, 2 or 5 μM) for 24 h, cells were collected and cell cycle was then analyzed using propidium iodide staining and flow cytometry. Data represent mean ± SD from three independent experiments (**p < 0.01, ***p < 0.001 vs. DMSO-treated group). (c) KYSE150 cells were treated with DMSO or deguelin (2 μM) for 24 h and then were evaluated by immunofluorescence assay by staining with anti-α-tubulin (green) and DAPI (blue). Scale bar, 20 μm.