Cyclic AMP‐dependent and ‐independent protein kinases and protein phosphorylation in human promyelocytic leukemia (HL60) cells induced to differentiate by retinoic acid

Abstract

The human leukemia cell line HL60 which resembles promyelocytes can be induced to differentiate to cells displaying features of the mature myeloid phenotype by a variety of agents including retinoic acid (RA) and agents that elevate intracellular adenosine 3:5 cyclic monophosphate (cyclic AMP) levels, e.g., 8-bromo-cyclic adenosine 3:5 monophosphate (8-Br-cyclic AMP), cholera toxin. Since most, if not all the effects of cyclic AMP, are mediated by adenosine 3:5 cyclic monophosphate-dependent protein kinase (cyclic AMP-dPK), we investigated the role of cyclic AMP-dPK and adenosine 3:5 cyclic monophosphate-independent protein kinase (cyclic AMP-iPK) in the induced differentiation of HL60 cells. Marked stimulation of cyclic AMP-dPK and cyclic AMP-iPK appears to be intimately involved with and specific for HL60 myeloid differentiation as evidenced by: (1) Stimulation of cyclic AMP-dPK and cyclic AMP-iPK early during HL60 myeloid differentiation and prior to phenotypic changes. (2) RA and dimethylformamide (DMF), agents that induce differentiation along the myeloid pathway, cause a marked increase in the type l cytosolic cyclic AMP-dPK and cyclic AMP-iPK (protamine kinase) while no such increases are noted in cells treated with 12-0-tetradecanoyl-phorbol-13-acetate (TPA) which induces differentiation along the monocyte/macrophage pathway. (3) Both native polyacrylamide gel electrophoresis as well as photoaffinity labeling with 8-azido-cyclic AMP demonstrate marked increases in type l cyclic AMP-dPK in the cytosols of cells exposed to agents that induce myeloid differentiation but no increase in TPA-differentiated cells. (4) The appearance and disappearance of specific cyclic AMP-dependent and -independent protein phosphorylations are associated with the induced myeloid differentiated state.

Abnormal Expression of Neurofilament Proteins in Ewing’s Sarcoma Cell Cultures

“…When the cell lines were cultured with TPA or RA, the 68-kD subunit was slightly induced. TPA and RA have been described to induce cell differentia tion of various cell types including murine and human neuroblastoma cells [11][12][13][14][15] and a wild type of leukemia cell line [16][17][18]. The observation that TPA may induce a major reorganization of cytoskeletal components [19,20] could explain the more significant induction of the 68 kD obtained with TPA than with RA, in 2 of the 3 cell lines tested.…”

Protein kinase C and cAMP-dependent protein kinase regulate the neuronal differentiation of immortalized raphe neurons

“…Thus, PKC and PKA regulate a variety of developmental and mature neuronal and nonneuronal processes. Additional studies demonstrated differentiation-specific alterations in PKC and PKA activities (Abraham et al, 1991;Durham et al, 1985;Fontana et al, 1984;Kraft and Anderson, 1993;Plet et al, 1985Plet et al, , 1986Plet et al, , 1987Wooten et al, 1992). These data suggest that alterations in PKC and PKA activities are associated with the development of the mature cellular phenotype.…”

Characteristics of Cyclic AMP Enhancement of Retinoic Acid Induction of Increased Transglutaminase Activity in HL60 Cells

“…RA stimulated translocation of the type II protein kinase from the cytosol to the plasma membrane in the F9 cells and to the nucleus in the erythroleukemia cells. Fon-tona et al [36] reported changes in protein phosphorylation patterns and an increase in the type I protein kinase of HL60 cells 24 h after treatment with 1 pM RA. No reproduc ible changes were found in intracellular cAMP content in HL60 cells in response to RA or DMSO [37], Cyclic AMP or its analogues alone did not markedly increase TGase activity in HL60 cells.…”