Effects of the c-AMP analogue 8Br-cAMP on BCRP promoter activity and BCRP mRNA expression. Cells were cultured in 24-well plates and transfected with pGL4 empty vector or pGL4/1285, a reporter construct containing the promoter region (-1285/+362) of BCRP, respectively. After culture overnight in SFM, cells were treated with 8Br-cAMP (2 mM, final concentration) for 6 hours, then luciferase activity was determined for IGROV1 cells (A) and MDAMB468 cells (B). IGROV1 cells were treated with 2 mM 8Br-cAMP for 6 hours after culture overnight in SFM, then total RNA was isolated and BCRP mRNA expression was determined by real time qPCR (C). Results represent the means ± S.D. from three separate experiments, each done with triplicate determinations per data point. *, significantly (P<0.05) different vs. untreated, Student's t-test.