Complex regulation of macrophage colony-stimulating factor in the HL-60 promyelocytic cell line.

The regulation of macrophage colony-stimulating factor (M-CSF) gene expression by phorbol esters and calcium ionophore (A23187) was studied in HL-60 cells. In untreated HL-60 cells, M-CSF transcripts were undetectable, but transcripts were present within 2 h of A23187 treatment or within 8 h of phorbol 12,13-dibutyrate (PdBu) treatment. Concurrent treatment of HL-60 cells with A23187 and cycloheximide (CHX) for 6 h led to a superinduction of message over A23187 treatment alone.

Multiple calcium-mediated mechanisms regulate c-myc expression in HL-60 cells.

Treatment of human promyelocytic leukemia cells (HL-60) with the calcium ionophore A23187 induced a biphasic change in the expression of the c-myc protooncogene. Within 1 h of exposure to a single 2.5-microM dose of A23187, steady state levels of c-myc mRNA increased to 170% of control.

Localization of collagenase mRNA in rheumatoid arthritis synovium by in situ hybridization histochemistry.

Collagenase has been implicated as playing an important role in the connective tissue destruction that is a major feature of rheumatoid arthritis. Numerous cell types in the hyperplastic rheumatoid synovium are capable of synthesizing collagenase. Past studies have used predominantly synovial fibroblasts in culture as a model system for the regulation of collagenase production, but the major cellular source of the enzyme in vivo has not been determined.

Regulation of human synovial fibroblast collagenase messenger RNA by interleukin-1.

Interleukin-1 (IL-1) may contribute to tissue destruction in rheumatoid arthritis, in part, by inducing messenger RNA (mRNA) that encodes interstitial collagenase. In human synovial fibroblasts in vitro, IL-1 induced collagenase mRNA accumulation 6 hours after being added to the cells. High levels of mRNA remained present for at least 48 hours after treatment.

Dynamics of the diradylglycerol responses of stimulated phagocytes.

The generation of diradylglycerols (sn-1,2 diacylglycerols (DAG) and 1-O-alkyl-2-acylglycerols (AAG] was investigated in human polymorphonuclear leukocytes stimulated with fMet-Leu-Phe, phorbol myristate acetate (PMA), or A23187. With each stimulus, the elevations in the mass of DAG clearly preceded that of AAG. The levels of both lipids increased over time, peaked by 15-20 min (fMet-Leu-Phe) or 45-60 min (PMA or A23187) and returned slowly toward base line thereafter.

Constitutive production of macrophage colony-stimulating factor by human ovarian and breast cancer cell lines.

Many nonhematologic tumors produce growth factors that may influence cellular proliferation either by autocrine or by paracrine mechanisms. In the current study, human tumor cell lines were investigated for the constitutive production of macrophage colony-stimulating factor (M-CSF). Culture supernatants obtained from cell lines were analyzed using a radioimmunoassay and a radioreceptor assay specific for M-CSF.

Human thymic epithelial cells produce granulocyte and macrophage colony-stimulating factors.

The development of culture conditions for growing normal human thymic epithelial (TE) cells free from contamination with other stromal cells has allowed us to identify and characterize TE cell-derived cytokines. In this study, we report that cultured human TE cells produced CSF that supported the growth of clonal hematopoietic progenitor cells in the light density fraction of human bone marrow cells. Thymic epithelial supernatants (TES) induced growth of granulocyte/macrophage colonies (CFU-GM), mixed granulocyte/erythrocyte/monocyte/megakaryocyte colonies (CFU-GEMM), and early burst-forming unit erythroid colonies (BFU-E).

Transcription interruption may be a common mechanism of c-myc regulation during HL-60 differentiation.

Human promyelocytic leukemia cells (HL-60) differentiate along a monocytoid pathway in response to recombinant human tumor necrosis factor or recombinant human interferon gamma. Together, these agents act synergistically to induce phenotypic differentiation. Since reduced expression of mRNA for the proto-oncogene c-myc correlates with differentiation of HL-60 cells induced by other agents, we tested the abilities of tumor necrosis factor and interferon gamma to regulate expression of c-myc mRNA.

Dioctanoylglycerol and phorbol esters regulate transcription of c-myc in human promyelocytic leukemia cells.

Treatment of human promyelocytic leukemia cells (HL-60) with phorbol 12-myristate 13-acetate or phorbol 12,13-dibutyrate (PDBu) caused a rapid decrease in transcription of the c-myc protooncogene. In the continuous presence of PMA or PDBu, the rate of transcription of c-myc decreased to 20% of control within 2 h and was maintained at 20-30% of the control level for the ensuing 24 h. Cell-permeable sn-1,2-dioctanoylglycerol (diC8), a diacylglycerol analogue, also caused a rapid decrease in c-myc transcription.

Phorbol diesters and dioctanoylglycerol stimulate accumulation of both diacylglycerols and alkylacylglycerols in human neutrophils.

Human neutrophils treated with phorbol 12-myristate 13-acetate (PMA) or dioctanoylglycerol exhibited a large (10-fold), sustained accumulation of the mass of diradylglycerol, beginning 1 min after stimulation and continuing for 30 to 60 min. Phorbol dibutyrate was less potent than PMA in stimulating diradylglycerol accumulation, whereas the 4-alpha analogs of PMA and phorbol dibutyrate were inactive. Submaximal concentrations of PMA (0.

Diacylglycerol accumulation and superoxide anion production in stimulated human neutrophils.

Exogenous diacylglycerols stimulate neutrophil superoxide anion production, suggesting that endogenous diacylglycerols may function as second messengers for this biological response. We have measured the diacylglycerol mass in human neutrophils stimulated by fMet-Leu-Phe, ionomycin, and concanavalin A and have correlated the kinetics and magnitude of the diacylglycerol response with those for superoxide anion production. For each stimulus, no increase in diacylglycerol mass was detected prior to the onset of superoxide anion generation.

Distinct patterns of expression of different protein kinase C mRNAs in rat tissues.

The identification of multiple protein kinase C (PKC) cDNA sequences from rat, bovine, and human tissues has led to the discovery of a family of PKC genes. Using probes complementary to three cDNA sequences from rat brain, designated PKC-I, -II, and -III, the distribution of PKC transcripts in rat tissues was studied by in situ hybridization histochemistry. In brain, PKC-II and PKC-III transcripts colocalized except in the brain stem and spinal cord, where some cells appeared to contain only PKC-III message.

Diacylglycerol mass measurements in stimulated HL-60 phagocytes.

The mass of sn-1,2-diacylglycerol in crude lipid extracts from differentiated HL-60 phagocytes was measured by quantitative conversion of the diacylglycerol to [32P]-labeled phosphatidic acid catalyzed by E. coli diacylglycerol kinase. The chemotactic peptide N-formyl-Met-Leu-Phe caused a time- and concentration-dependent increase in diacylglycerol that was maximal at 4 min.

Cytochalasin B enhancement of the diacylglycerol response in formyl peptide-stimulated neutrophils.

Diacylglycerol has gained wide acceptance as an important second messenger in the signal transduction mechanism by which occupancy of certain membrane receptors such as the formyl peptide receptor of neutrophils leads to biological responses, but supporting evidence for this proposed role is limited. We have utilized a recently developed diacylglycerol kinase assay (Preiss, J. E.

Dibutyryl cyclic adenosine monophosphate reduces expression of c-myc during HL-60 differentiation.

The human promyelocytic leukemia cell line HL-60 is induced to differentiate along a myelocytic pathway by dibutyryl cyclic adenosine monophosphate (dbcAMP). Other cAMP analogs are ineffective as inducing agents. The effect of these compounds on expression of c-myc was investigated using a DNA probe for c-myc to detect RNA transcripts.

Quantitative measurement of sn-1,2-diacylglycerols present in platelets, hepatocytes, and ras- and sis-transformed normal rat kidney cells.

A simple enzymatic method for the quantitation of the mass of sn-1,2-diacylglycerol (DAG) present in crude lipid extracts was developed to assess the function of DAGs as intracellular "second messengers" of extracellular agents and of oncogene products. The assay employed Escherichia coli DAG kinase which constituted approximately 15% of the membrane protein of a plasmid-bearing strain and defined mixed micellar conditions to solubilize the DAG present and allow its quantitative conversion to [32P]phosphatidic acid. The assay was proportional with the amount of DAG added over the range of 25 pmol to 25 nmol.

Differential stimulation of the respiratory burst and lysosomal enzyme secretion in human polymorphonuclear leukocytes by synthetic diacylglycerols.

Binding of chemoattractants to receptors on human polymorphonuclear leukocytes (PMN) stimulates the phosphodiesteric cleavage of phosphatidylinositol 4,5-bisphosphate to produce inositol 1,4,5-trisphosphate and 1,2-diacylglycerols. To investigate the possible second messenger function of diacylglycerols in PMN activation, we tested the ability of a series of synthetic sn 1,2-diacylglycerols, known to stimulate protein kinase C in other systems, to promote superoxide anion release, oxygen consumption, lysosomal enzyme secretion, and chemotaxis. None of the diacylglycerols initiated the chemotactic migration of PMN.

Induction of myeloid differentiation of HL-60 cells with naphthalene sulfonamide calmodulin antagonists.

The naphthalene sulfonamide calmodulin antagonists, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide and N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide, both induce limited myeloid differentiation of the human promyelocytic cell line, HL-60. In addition, these inhibitors augment the differentiation observed when HL-60 cells are induced with retinoic acid, dimethyl sulfoxide, or dibutyryl cyclic adenosine monophosphate. The dose-response curve for HL-60 differentiation was consistent with the published 50% inhibitory dose for inhibition of calmodulin-activated phosphodiesterase and with the calmodulin drug-binding potential of N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide and N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide and their less active congeners, N-(6-aminohexyl)-1-naphthalenesulfonamide and N-(4-aminobutyl)-2-naphthalenesulfonamide.

Cytosolic calcium regulates phorbol diester binding affinity in intact phagocytes.

The mobilization of internally sequestered stores of Ca2+ and activation of protein kinase C appear to be involved in neutrophil activation. We have examined the inter-relationship of these two pathways by investigating the effects of modulating Ca2+ activity on the binding of [3H]phorbol 12,13-dibutyrate (PDBU) to protein kinase C in intact phagocytes. Differentiated HL-60 cells were equilibrated with [3H]PDBU prior to stimulation with various agents known to alter Ca2+ homeostasis in cells.

Cyclic AMP levels and cellular kinetics during maturation of human promyelocytic leukemia cells.

Differentiation of human promyelocytic leukemia cells (HL-60) in response to several classes of inducing agents is characterized by the sequential appearance of granulocytic or monocytic markers. Compounds that increase intracellular cAMP in HL-60 cells induce a program of maturation in which cells demonstrate early functional phagocytic properties. Cyclic nucleotide metabolism was studied during monocytic and granulocytic differentiation of the HL-60 cell line.

Pertussis toxin inhibits chemotactic peptide-stimulated generation of inositol phosphates and lysosomal enzyme secretion in human leukemic (HL-60) cells.

The binding of the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine to its cell surface receptor rapidly elicits the hydrolysis of phosphatidylinositol 4,5-bisphosphate by phospholipase C to form the putative second messengers inositol 1,4,5-trisphosphate and sn-1,2-diacylglycerol. To investigate the possible role of a guanine nucleotide binding protein in transduction of this membrane signal, we examined the effects of pertussis toxin on chemotactic peptide-stimulated inositol phospholipid metabolism in differentiated HL-60 cells labeled with [3H]inositol. Pertussis toxin inhibited the chemotactic tripeptide-stimulated production of inositol mono-, bis-, and trisphosphates and secretion of N-acetyl-beta-D-glucosaminidase in a time- and concentration-dependent manner.

Affinity labeling of the Fc receptor on human monocytes using bifunctional cross-linking agents.

To affinity label the Fc receptor on human monocytes, Fc fragments of monoclonal human IgG1 radiolabeled with iodine 125 were covalently bound to the surface of intact monocytes using a variety of bifunctional cross-linking agents including ethylene glycol bis(succinimidyl succinate), dithio-bis-(succinimidyl proprionate), maleimidobenzoyl N-hydroxysuccinimide, glutaraldehyde and dimethyl suberimidate. After cross-linking, cells were solubilized and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, followed by radioautography. Each of these cross-linkers caused a portion of cell-bound Fc fragments to form a covalent complex with a monocyte membrane component.

Diacylglycerols mimic phorbol diester induction of leukemic cell differentiation.

Activation of cellular protein kinase C appears to be involved in the mechanism by which phorbol diesters induce differentiation of human myeloid leukemia cells (HL-60). Protein kinase C is thought to be physiologically activated by diacylglycerol derived from receptor-mediated phosphatidylinositol hydrolysis. sn-1,2-diacylglycerols with short saturated acyl side chains (C4-C10) were synthesized and found to be potent activators of protein kinase C partially purified from HL-60 cells.