title: Rapid down-regulation of protein kinase C and membrane association in phorbol ester-treated leukemia cells.
abstract: Peripheral blood lymphocytes from patients with chronic lymphocytic leukemia (CLL) acquire after several days of exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA) several morphological, immunological and histochemical features of hairy cell leukemia. We have investigated the short term effects of TPA treatment on protein kinase C and its subcellular distribution. Within minutes of addition of TPA to CLL cells 20% of the cytosolic protein kinase C had associated with the particulate fraction. The remaining 80% of protein kinase C activity was down-regulated. The association with the membrane dramatically increased the resistance of the enzyme to inhibition by the non-ionic detergent, Triton X-100. These results suggest that activation of protein kinase C causes multiple biological changes in CLL cells.
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D006801:Humans; D007945:Leukemia, Lymphoid / Q000097:blood / Q000201:enzymology*; D008214:Lymphocytes / Q000201:enzymology; D017830:Octoxynol; D010703:Phorbol Esters / Q000494:pharmacology*; D011092:Polyethylene Glycols / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D013347:Subcellular Fractions / Q000201:enzymology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D010703:Phorbol Esters; D011092:Polyethylene Glycols; D017830:Octoxynol; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate