<p>MCF-7 cells were treated with vehicle (<b>A</b>) or 10 nM E<sub>2</sub> (<b>C</b>), or 10 μM each of lignans (<b>E</b>, <b>G</b>, <b>I</b>, <b>K</b>, and <b>M</b>) for the indicated times. Cell extracts were subjected to Western blot analysis for cyclin D1, CDK4, cyclin E and β-actin (control). The results of three independent experiments are summarized along with the statistical evaluation in panels <b>D</b> (for E<sub>2</sub>), and <b>F</b>, <b>H</b>, <b>J</b>, <b>L</b> and <b>N</b> (for lignans). Statistical significance of data compared with the negative control (lane 1) is shown as * (<i>p</i> < 0.05).</p
