CAP1 and cancer: Next, we inhibited GSK3 by treating cancer cells with a potent GSK3 inhibitor 6-BIO (6-bromoindirubin-3′-oxime)31 and found that the treatment reduced S308/S310 phosphorylation on CAP1 in PANC-1 and CFPAC-1 cells, in a dose-dependent manner (Fig. 1C, shown for PANC-1 cells only).