B2G2-isolated and synthetic B2G2 inhibit growth and induce death in A) PC3, B) 22Rv1 and C) C4-2B cells in both dose- and time- dependent manner. Cells (1.05 x 105) were plated in 60 mm dishes, treated with DMSO (control) or different concentrations of B2G2, and after 24, 48 or 72 h, cells were harvested and counted as detailed in “Materials and methods”. C, control; B2G2, procyanidin B2 3,3″-di-O-gallate.