DFMO inhibits ESCC cells in vitro. a The effect of DFMO on ODC activity in KYSE450 and KYSE510 cells was measured as the release of CO2 from L-[1-C14] ornithine and results are shown as percentage of control group (set at 100%). b Anchorage-dependent cell growth was measured by MTS assay. c For measuring anchorage-independent growth, cells were cultured for 3 weeks with different concentrations of DFMO in soft agar and then colonies were counted using a microscope and the Image-Pro Plus software (v.6.0) program. After treatment with DFMO for 72 h, d total apoptosis and e cell cycle were analyzed by flow cytometry. The expression of markers associated with cell cycle and apoptosis was analyzed by Western blot. All data are shown as means ± S.D. of triplicate values from 3 independent experiments