Expression for mRNA for the MDR-1, MRP-1, and BCRP in human ovarian cancer cell lines as revealed by real-time PCR. PCR products were separated by 1.8% agarose gel and stained with ethidium bromide. Lanes 1 and 2, OV-1063; lanes 3 and 4, ES-2; lanes 5 and 6, UCI-107; lane 7, negative control; lane 8, positive control.