Depletion of RAD21 prevents estradiol activation of <i>MYC</i> in MCF7 cells.

<p><b>A)</b><b><i>RAD21</i></b><b> silencing in MCF7 cells.</b> RAD21 protein levels were reduced 24 hours after transfection and completely depleted 48 hours after transfection with 10 nM RAD21 siRNA <b>B)</b><b>RAD21 positively regulates </b><b><i>MYC</i></b><b> in MCF7</b><b>cells</b>. Relative levels of <i>MYC</i> mRNA in Control (CON) and RAD21 siRNA transfected MCF7 cells were determined by qRT-PCR. Columns show the average values of relative normalized expression from three independent experiments. The * symbol indicates a significant (p<0.05) reduction in <i>MYC</i> transcript levels in RAD21 depleted MCF7 cells compared with cells transfected with Control siRNA. <b>C)</b><b>Estradiol-activation of </b><b><i>MYC</i></b><b> is ERα- and RAD21-dependent</b>. MCF7 cells were transfected with Control (CON), RAD21 or ESR1 siRNA for 48 hours and then treated with vehicle (V) or estradiol (E) for 6 hours. <i>MYC</i> transcript levels are shown relative to Control siRNA + V treated cells. The results shown are the mean (+/− SEM) of 3 biological replicates. The **** symbol indicates a highly significant (p<0.001) reduction in <i>MYC</i> expression in RAD21 and ESR1 siRNA transfected cells treated with estradiol compared with Control siRNA transfected cells treated with estradiol.