OBJECTIVETo explore the effect of arsenic trioxide combined with itraconazole on proliferation and apoptosis of KG1a cells and its potential mechanism.

METHODSThe cell morphology was observed with Wrighe-Giemsa staining; cell survival rate was examined by CCK-8; and colony formation capacity was measured by methylcellulose colony formation test; the flow cytometry was used to analyse the cell apoptosis rate and cell cycle; the protein expressions of BCL-2,caspase-3,BAX,SMO,Gli1 and Gli2 were detected by Western-blot.

RESULTSThe arsenic trioxide and itraconazole alone both could inhibit the KG1a cell proliferation in dose-and time-dependent manner. In comparison between single and combined drug-treatment group, both the cell survival rate and the colony number of the single drug-treatment group were significantly lower(P<0.05), and the apoptosis rate was higher in the combined drug-treatment group. In the combined-treatment group, the protein expression of Caspase-3 and BAX was upregulated, while the protein expression of BCL-2,SMO,Gli1 and Gli2 was downregulated.

CONCLUSIONArsenic trioxide combined with itraconazole can inhibit the KG1a cell proliferation and induce apoptosis, which may be related with the inhibition of Hh signaling pathway and upregulation of both Caspase-3 and BAX protein expression, and provided experimental data of arsenic trioxide combined with itraconazole for the treatment of refractory AML.