CDDO-Me inhibition of cell growth and induction of apoptosis in HL-60 cells.

HL-60 cells were incubated with different concentrations (0.05, 0.1, 0.5 μM) of CDDO-Me or DMSO (control) for 96 hours. The effect on cell growth was examined by cell count (A). Apoptosis was measured by staining with fluorescein isothiocyanate-labeled annexin V, which binds phosphatidylserine with high affinity (B). Cells were simultaneously stained with PI and analyzed by flow cytometry. At 0.5 μM CDDO-Me, more than 95% of cells were annexin V–PI-positive at 48 hours (not shown).