ABCG2 and cancer: The ABCB1 and ABCG2 transporters are overexpressed in certain MDR cancer cells compared to their corresponding parental cells.[12] Furthermore, certain metal complexes can be extruded from cancer cells due to the overexpression of some transporters.[13] Thus, designing metal complexes 1) that disrupt cancer cell metabolism and 2) escape drug efflux by ABC transporters could yield molecules that are efficacious in MDR cancer cells.