In vitro effect of HMA on AML cell lines. (A) MOLM-13 and MV4-11 were most sensitive to HMA compared with THP-1. (B) HMA reduced pHi in (i) MOLM-13 and (ii) MV4-11 in a dose-dependent manner. (C) HMA also induced apoptosis in (i) MOLM-13 and (ii) MV4-11 cells. (D) In MV4-11 cells, the number of colony-forming cells was significantly reduced by HMA treatment compared with vehicle control. (ii) Representative photo showing the reduced number of colony in HMA-treated MV4-11 cells.