(a) Silymarin inhibited cell‐cycle progression in HepG2 cells: (a), (b) and (c) showing representative histograms of HepG2 control, 50 µg/ml of silymarin, and 75 µg/ml of silymarin, respectively. (d) Quantitative analysis of apoptotic cell population. P < 0.05 compared with aHepG2 control, b50 µg/ml silymarin and c75 µg/ml silymarin. (b) Silymarin down‐regulated expression of proliferation‐associated proteins β‐catenin, cyclin D1, cMyc and PCNA in HepG2 cells. Lanes l, 2 and 3 correspond to lysates of HepG2 control, 50 µg/ml of silymarin, and 75 µg/ml of silymarin, respectively.