Possible role of calmodulin in stimulation of hexose transport by 12-O-tetradecanoylphorbol-13-acetate, a tumor promoter.

12-O-tetradecanoylphorbol-13-acetate (TPA), a potent tumor promoter stimulated the rate of 2-deoxy-D-glucose (2DG) transport. Three different kinds of calmodulin antagonists inhibited the TPA-stimulated 2DG transport, the mechanism of which was examined in kinetic analysis. These results indicate that the expression of the effect of TPA may depend on Ca2+-calmodulin system.