Downregulation of MRP1 decreased MDR1 expression in MC3/5FU cells.

<p>MC3/5FU cells were transfected with plasmids containing a ABCC1/MRP1 specific shRNA and a non-specific control shRNA, the resulting clones were MC3/5FU–S (S for silenced) and MC3/5FU-NS (NS for non-silenced). Total RNA and total protein were extracted from the 2 cell lines and then subjected to RT-PCR and Western blot respectively. (A) Quantitative real-time RT–PCR result (n = 3). The values were nomalized with GAPDH. When ABCC1/MRP1 mRNA was significantly down-regulated in MC3/5FU-S cell, ABCB1/MDR1 mRNA was simultaneously significantly down-regulated. (B) Representative RT-PCR results (n = 3). GAPDH was used as loading control. (C) Representative Western-blot results. β-actin was used as loading control. ** P<0.01 vs MC3/5FU-S, *** P<0.001 vs MC3/5FU-S.