title: Different effects of the two protein kinase C activators bryostatin-1 and TPA on growth and differentiation of human monocytic leukemia cell lines.
abstract: The effects of bryostatin-1 (Bryo) and 12-O-tetradecanoyl-phorbol 13-acetate (TPA), both activators of protein kinase C (PKC), on proliferation and differentiation of two monocytic leukemia cell lines, JOSK-I and JOSK-M, were investigated. Treatment with TPA or Bryo inhibited cellular proliferation in a dose-dependent manner. Both drugs induced distinct phenotypic changes associated with monocytic differentiation. Although c-myc mRNA is often found to be down-regulated during biomodulator-triggered in vitro myelomonocytic differentiation, however, here the modulation of c-myc expression was less pronounced. All parameters studied were more prominently altered in TPA- than in Bryo-treated cells, and, were more distinct in JOSK-I than in JOSK-M. Since Bryo was able to antagonize the TPA-mediated effects on proliferation and morphological alterations, an (at least partially) different mode of action of these PKC activators on monocytic cell lines may be suggested.
authors.affiliation: DSM-German Collection of Microorganisms and Cell Cultures, Department of Human and Animal Cell Cultures, Braunschweig.
authors.forename: K G
authors.initials: KG
authors.lastname: Steube
authors.forename: D
authors.initials: D
authors.lastname: Grunicke
authors.forename: H
authors.initials: H
authors.lastname: Quentmeier
authors.forename: H G
authors.initials: HG
authors.lastname: Drexler
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology*; D054713:Bryostatins; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D006801:Humans; D007783:Lactones / Q000494:pharmacology*; D007948:Leukemia, Monocytic, Acute / Q000378:metabolism / Q000473:pathology*; D018942:Macrolides; D008297:Male; D011493:Protein Kinase C / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000473:pathology
chemical_list: D000970:Antineoplastic Agents; D054713:Bryostatins; D007783:Lactones; D018942:Macrolides; D016271:Proto-Oncogene Proteins c-myc; C046785:bryostatin 1; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate