After LNCaP-P8, LNCaP-P121-C2, LNCaP-P121-C1, and DU145 cells were cultured in a 6-well plate to 70–80% confluence, cells in the center area were removed with a pipette tip and allowed to refill the space. The migration rates, μm/h, of duplicate samples were measured at 0, 4, 10 and 22 h and the images of 0 and 22 h are shown. The migration rates are shown in Table 1.