The resultsshowed that the cellular uptake of LAT1-utilizing prodrugs into ahuman breast cancer cell line, MCF-7 cells, was mediated via SNATsas the uptake was increased at higher pH (8.5), decreased in the absenceof sodium, and inhibited in the presence of unselective SNAT-inhibitor,(α-(methylamino)isobutyric acid, MeAIB). This evidence concerns the gene AANAT and breast cancer.