Figure 3.

Silibinin inhibits serum- and DHT-stimulated growth of LNCaP cells. (A) Dose- and time-dependent inhibitory effect of silibinin on serum-stimulated cell growth. Cells were treated with ethanol (control) or indicated doses of silibinin. (B) Inhibitory effect of silibinin on DHT-stimulated cell growth. Cells were grown in FBS, 10% serum; FBS + silibinin, 10% serum + 50 μg/ml of silibinin; cFBS, 10% cFBS; cFBS + DHT, 10% cFBS + 1 nM DHT; or cFBS + DHT + silibinin, 10% cFBS + 1 nM DHT + 50 μg/ml of silibinin. The data in B are at 5 days of cultures; silibinin was added at day 4. After desired treatments, cells were trypsinized and counted as described in Materials and Methods. Each data point represents mean ± SE of four independent plates; each sample was counted in duplicate.