<p>(A) Protein levels of Ac-H3 and Ac-H4, extracted from OME-treated cells, were detected by western blot using antibodies specific for the modified histone (Ac-H3) and Ac-H4. β-actin was used as loading control. (B) Immunofluorescence staining of Ac-H3 and Ac-H4 in MDA-MB231 cells treated with 150, 300 and 450 µg/mL of OME or equal volume of vehicle (ethanol) as control for 24 h. Cells were fixed, permeabilized, and then processed for immunofluorescence using antibodies against the indicated modified histones. DAPI was used as a nuclear stain.</p