Figure 3.

Effects of calcium channel blockers on the expression of pS2

MCF7-2A cells were grown in phenol red free IMEM supplemented with 5% CFBS. MCF-7 cells were grown in phenol red containing IMEM supplemented with 10% fetal bovine serum; prior to treatment, the media of MCF-7 cells was changed to phenol red free IMEM containing 5% CCS for 48 hours. The cells were treated for 48 or 72 hours with methoxyverapamil (MV; 75 μM) and/or mibefradil (MF; 5 μM) in the absence and presence of 17β-estradiol (E2; 1 nM), 4-hydroxy tamoxifen (TAM; 1 μM), or ICI-182,780 (ICI; 100 nM). RNA was isolated. The amount of pS2 mRNA was measured using a quantitative real time-PCR assay and normalized to the expression of ribosomal large protein P0 (RPLP0) mRNA using the 2^−ΔΔCt method. Data are presented as fold change compared to control. (mean ± SEM; n ≥ 3; a, 48 hours; b, 72 hours; *, p≤0.05; **, p≤0.01; ***, p≤0.001; ****, p≤0.0001). panel A, MCF7-2A cells; panel B, MCF-7 cells.