Novel methods for modulating acute myeloid leukemia stem/progenitor cell expansion and/or differentiation are disclosed. These methods are based on the use of aryl hydrocarbon receptor (AhR) modulators and/or compounds of formula I or IIScreening assays to identify compounds that may be useful for inhibiting and/or eliminating AML initiating cells using AhR modulators and/or the compounds of formula I or II are also disclosed. The use of pharmaceutically acceptable agonists of the AhR for preventing or inhibiting minimal residual disease (MRD) in an AML patient is also disclosed.