Figure 5.

Increased trimethylation of lysine 27 on histone H3 by silibinin is associated with decreased pAkt levels. PC3 cells were treated with different concentrations of silibinin (25–75 μg/mL) and PI3K inhibitor LY294002 (10–20 μΜ) for 48 h. Cytosolic and nuclear extracts were analyzed for pAkt (ser473) and H3K27me3 by western blotting, respectively. Representative blots are shown. Equal protein loading was verified by stripping and re-probing the same membranes with tubulin and lamin-β (upper panel). Quantification of pAkt (ser473) and H3K27me3 bands was performed by scanning densitometry (lower panel). The results are presented as the mean ± SD of three or more independent experiments. * p < 0.05, ** p < 0.01, *** p < 0.001.