In addition, 3′,4′,5′-trimethoxy-, 2′,3′,4′-trimethoxy-, and 2′,5′-dimethoxy units are favourable for the antiproliferative activity of chalcones on human MDR1 gene-transfected mouse lymphoma cells, especially, when p-dimethylamino group was present in the ring B. Here, ABCB1 is linked to lymphoma.