Oleic acid decreases BCRP mediated efflux of mitoxantrone in Caco-2 cell monolayers

► Oleic acid, dose dependently increased transport of mitoxantrone, a BCRP substrate, across Caco-2 cell monolayers. ► Oleic acid increased gene expression of BCRP in Caco-2 cells after 6 h exposure. ► Accumulation of mitoxantrone in Caco-2 cells increased when cells were exposed to oleic acid at 2 mM or higher. ► The effect of oleic acid on mitoxantrone transport was not dependent on the presence of the oleic acid emulsion.