C646 inhibited proliferation of AE-positive AML cell lines through inducing cell cycle arrest and apoptosis.

<p>The cultured AE-positive AML cell lines Kasumi-1 and SKNO-1 cells were treated with given doses of C646 or 0.1% DMSO for 24 h before being subjected to the following assays. (A) C646-induced growth inhibition in both cell lines was detected by Cell Counting Kit-8 at the indicated times; means ± SD of 3 independent experiments. (B) C646-evoked ablation of leukemia colony-forming units in both cell lines was performed by colony formation assay. (C) Dose-dependent retardance of C646 on cell cycle distribution in both cell lines. The cells were stained with propidium iodide and measured by flow cytometry. (D) Dose- and time-dependent effects of C646 on apoptosis in both cell lines. The cells were stained with Annexin V-FITC and measured by flow cytometry. Histograms showed means ± SD of 3 independent experiments. * <i>P</i><0.05. (E) C646 triggered caspase cleavage in Kasumi-1 cells. The Kasumi-1 cells treated with given doses of C646 in the presence or absence of 50 µM pan-caspase inhibitor Q-VD-OPH were collected and lysed at the indicated time points, and western blotting performed with the indicated antibodies. Equalization of protein loading was verified on the same membrane by reprobing after stripping. Data shown were representative of 2 independent experiments.