Induction of MsrB1 by 5-Aza-dC. (A) MDA-MB231 cells were treated with 10 μM 5-Aza-dC as described. MsrB1 expression was detected by RT-PCR. The change in MsrB1 mRNA level is indicated relative to the basal (non treated) level of MsrB1 mRNA. GAPDH mRNA was amplified as a control. (B) whole cell extracts were prepared from MDA-MB231 cells treated with 10 μM 5-Aza-dC and subjected to immunoblotting for MsrB1 protein expression. The membrane filters were re-probed with anti-β-actin antibody to verify the equal loading and integrity of samples. Data shown are representative of five independent experiments. The results are reported as mean ± S.D.; * P < 0.01.