Figure 3: (a) Protein levels of p53, p21, p16, PTEN, and p27 in 2BS cells grown from PD30 in DMEM supplemented with 1 mg/mL or 2 mg/mL pine pollen (PP). Representative images were acquired from three different experiments. (b) Quantitative analysis of the protein levels of p53, p21, p16, PTEN, and p27. Bars represent relative protein levels counted as (the value for PD30 control was set as 1.0), where and stand for the optical density of β-actin ladder and sample ladder, respectively. The optical density for each ladder was calculated by Image J soft ware. Data were obtained from three independent experiments. versus 30PD control group; versus 55PD control group.