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Sakurada K - - 1990
We examined the effect of bestatin (Ubenimex) on the growth of human leukemic cells (i.e, HL-60, K562, MT-1, MT-2, Molt-4, and Raji cells). The growth of each cell line was inhibited by the cocultivation with bestatin at higher concentrations than employed for clinical use in Japan. [3H]TdR incorporation was also ...
Aggeler J - - 1990
Rabbit synovial fibroblasts respond to changes in cell shape and cytoskeletal architecture by altering specific gene expression. We have tested the ability of acrylamide, a neurotoxin that alters the distribution of intermediate filaments in cultured PtK1 cells, to induce metalloprotease expression in synovial fibroblasts. Cells treated with 2-20 mM acrylamide ...
Fridman R - - 1990
The effect of the phorbol ester tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) on cell invasion was studied using an in vitro assay for cell invasion through a reconstituted basement membrane matrix (Matrigel). TPA inhibited the invasiveness of malignant human fibrosarcoma HT1080 cells. In contrast, WI-38 lung fibroblasts, which show a very ...
Pucillo C - - 1990
The expression of the low-affinity receptor for IgE Fc epsilon RII) in the human monocyte-like U-937 cell line can be upregulated by the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and by IgE. TPA induces terminal differentiation of U-937 cells and causes a four- to fivefold increase in the number of Fc epsilon ...
Kupfer A - - 1990
Previous experiments with individual cell couples formed between cloned T helper (Th) cells and antigen-presenting cells have led us to suggest that the cytoskeletal protein talin may be associated with the cell surface protein LFA-1 in the Th cell. In order to examine this suggestion, we induced the surface capping ...
Momparler R L - - 1990
5-Aza-2'-deoxycytidine (5-AZA-CdR), a potent inhibitor of DNA methylation and an active antileukemic agent, produced an induction of cytidine deaminase activity in human HL-60 myeloid leukemic cells. This increase in enzyme activity correlated with the induction of differentiation of the HL-60 leukemic cells as shown by an increase in nitroblue tetrazolium ...
Shiba Y - - 1989
The effect of a tumor-promoting phorbol ester on spreading behavior was investigated to clarify the involvement of the interactions between cells and substratum in the maintenance of cell viability and the control of cell proliferation. BSC-1 cells did not spread and lost cell viability after a 24-h incubation in the ...
Jalkanen J - - 1989
Human follicular fluid contains the insulin-like growth factor-binding protein (IGFBP-1) synthesized by ovarian granulosa cells. We studied the regulation of IGFBP-1 production by the granulosa-luteal cells from the hyperstimulated follicles of patients attending an in vitro fertilization program. The cells were first allowed to attach and recover from the hyperstimulation ...
Hsieh L L - - 1989
We have used a previously described retroviral expression vector pMV7-PKC beta 1 to develop derivatives of two rat liver epithelial cell lines, K16 and K22, that stably express about tenfold-higher PKC activity than control cells. Despite these high levels of PKC, these cells did not exhibit gross morphologic changes, anchorage-independent ...
Matsuzaki N - - 1989
We examined the nature of cytoplasmic signal transduction pathways in cord blood T cells by stimulating them with tumor promoter (TPA) and calcium ionophore (A23187). Costimulation of T cells with TPA and A23187 induced optimal proliferative responses on Day 2 in cord T cells but on Day 4 in adult ...
Heitman C R - - 1989
In this report we describe results showing that both arachidonic acid (20:4) release and prostaglandin (PG) synthesis in herpes simplex virus type 2 (HSV-2)-transformed tumor-derived rat fibrosarcoma (RFS) cells are inhibited by indomethacin (cyclooxygenase inhibitor). These data suggest that cyclooxygenase (prostaglandin endoperoxide synthetase, PES) and phospholipase are coupled in their ...
Costa-Casnellie M R - - 1989
Activation of neutrophils leading to superoxide production is accompanied by cytoplasmic alkalinization, which results from stimulation of the Na+/H+ exchanger. Since the exchanger undergoes permanent alterations during neutrophilic maturation of HL-60 cells (Costa-Casnellie et al.: Journal of Biological Chemistry 263:11851-11855, 1988), we investigated whether its response to external stimuli such ...
Duronio V - - 1989
The hemopoietic growth factor, interleukin 3, has been shown to activate protein kinase C without causing hydrolysis of inositol phospholipids. The potential involvement of phosphatidylcholine hydrolysis as an alternative source of diacylglycerol was investigated in an interleukin 3-dependent murine mast/megakaryocyte cell line, R6-XE.4. Treatment of these cells with interleukin 3 ...
Hii C S - - 1989
The phorbol ester, 12-tetradecanoylphorbol-13-acetate (TPA), stimulated the accumulation of labelled phosphatidylethanol (PEth) in HeLa cells prelabelled with [3H]hexadecanol and incubated in the presence of ethanol. PEth formation involves a phospholipase D-catalysed phosphatidyl transferase reaction. [3H]Hexadecanol labelled both ester- and ether-derivatives of HeLa cell phospholipids and TPA stimulated the conversion of ...
Tachibana A - - 1989
In order to examine the process of malignant transformation of human somatic cells, we studied the tumorigenic conversion of an Epstein-Barr-virus-immortalized lymphoblastoid cell line (LCL) derived from a patient with xeroderma pigmentosum (XP) complementation group A. Repeated irradiation of the XP cells, XP7NI, with UV-light and subsequent treatment with 12-O-tetradecanoylphorbol-13-acetate ...
Gailani D - - 1989
The human promyelocytic leukemia cell line HL-60 has an amplified number of copies of the protooncogene c-myc. It is induced to differentiate by exposure to the phorbol ester 12-O-tetradecanoyl phorbol-13-acetate (TPA). We have developed a mutant phorbol ester-tolerant (PET) line of HL-60 which undergoes a transient growth arrest but does ...
Hewison M - - 1989
In this study the effects of vitamin D metabolites on the myelomonocytic precursor cell line U937 have been compared with those of phorbol myristate acetate (PMA). PMA was used as a cell modulating agent in order to avoid effects of binding of the exogenous vitamin D metabolites receptors within the ...
Ladoux A - - 1989
Differentiation of HL60 cells into neutrophil-like cells after exposure to dimethylsulfoxide is accompanied by an increase in intracellular pH (pHi) which results from an increased activity of the Na+/H+ antiporter at physiological pHi value, but not at acidic pHi values. The functional responses of differentiated HL60 cells to the chemotactic ...
Ng C F - - 1989
Incubation of RBL-1 cells in the presence of 15-HPETE and various agonists generated lipoxins and several isomers. Addition of either A23187, fMLP or PMA modulated the number of isomers and amount of lipoxins produced. Administration of A23187 yielded the largest amount of product (5.3 +/- 1.6 micrograms per 10(8) cells) ...
Alvarez J - - 1989
The human cell line U937 differentiates to monocyte macrophage-like cells in response to tumour-promoting phorbol esters. This effect is attributed to activation of protein kinase C. We show here that U937 cell differentiation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) is associated with cytoplasmic alkalinization. Ethyl-isopropyl-amiloride (EIPA), a potent inhibitor of Na+/H+ ...
Krauss R S - - 1989
We have utilized a retroviral expression vector to construct a series of C3H/10T1/2 murine fibroblast cell lines that stably overexpress a full length cDNA encoding rat protein kinase C beta 1 (PKC). These cell lines contain 3-11 fold greater PKC enzyme activity than parental cells or control cells that carry ...
Kaiser H W - - 1989
Adducin is a protein recently purified from erythrocytes and brain that has properties in in vitro assays suggesting a role in assembly of a spectrin-actin lattice. This report describes the localization of adducin to plasma membranes of a variety of tissues and the discovery that adducin is concentrated at sites ...
de Rie M A - - 1989
We have produced five monoclonal antibodies (MoAb) directed against idiotypic determinants of surface immunoglobulins (sIg) expressed on malignant B cells from a patient suffering from prolymphatic leukaemia (B-PLL). The anti-idiotype MoAb were characterized by immunofluorescence-binding studies, allotype reactivity, and immunoprecipitation studies and were found to recognize at least two distinct ...
Cajander S B - - 1989
The observation that tissue-type plasminogen activator (tPA) activity increased dramatically in preovulatory follicles has led to the hypothesis that plasminogen activation is causally related to follicle rupture. With immunohistochemistry, we have studied the appearance of tPA in ovaries of immature rats induced to ovulate and in adult cycling rats. Treatment ...
Holán V - - 1989
Aminopterin, a folate antagonist, added to cultures of mouse spleen cells stimulated with T-cell mitogens markedly inhibited, in a dose-dependent manner, [3H]thymidine incorporation into the cells. Contrary to this inhibitory effect aminopterin added at the same concentrations to cell cultures stimulated with B-cell mitogens significantly increased [3H]thymidine incorporation. The inhibitory ...
Hoyer P B - - 1989
Enriched fractions of small and large luteal cells were incubated for 2 h with 1 or 10 microM calcium ionophore, A23187: unstimulated secretion of progesterone and viability in small cells were not affected but these measures were decreased (P less than 0.01) for unstimulated large cells and were significantly correlated ...
Koehler L - - 1989
The human undifferentiated histiocytic cell-line U937 can be induced to differentiate by incubation with 12-0-tetradecanoylphorbol-13-acetate (TPA) into macrophage-like cells. Dexamethasone reduced the prostaglandin production in TPA-differentiated U937 cells dose dependently, whereas undifferentiated U937 cells were dexamethasone insensitive. Concomitantly phospholipase A2, the enzyme liberating the prostaglandin precursor arachidonic acid, was inhibited ...
Truett A P AP - - 1989
Receptor-bypassing stimulants of human polymorphonuclear leukocytes (PMNLs), such as ionomycin or phorbol 12-myristate 13-acetate (PMA), generate an increase in diacylglycerol (DAG) which is independent of a phospholipase C specific for phosphatidylinositol 4,5,-bisphosphate (PIP2). Activation of a phospholipase C specific for phosphatidylcholine (PC) has been implicated as a source of DAG ...
Sato T - - 1989
A new megakaryoblastic cell line (CMK), which also exhibits erythroid and myeloid markers, was established from a Down's syndrome patient suffering from acute megakaryoblastic leukaemia. The CMK cells were found to be positive in reactions with anti-platelet antibodies (anti-glycoproteins IIb/IIIa and Ib, and Plt-1). Platelet peroxidase (PPO) reactivity was found ...
Pientong C - - 1989
The capability of herpes simplex virus type 1 (HSV-1), strain Angelotti (ANG), to replicate in human promyelocytic HL-60 cells treated with 1,2-tetradecanoyl-phorbol-13-acetate (TPA) and dimethyl sulfoxide (DMSO) was examined. Virus titrations and infectious center assays revealed that HSV-1 ANG replicated in nontreated HL-60 cells and in HL-60 cells treated with ...
Civitelli R - - 1989
Recent work indicates that PTH can stimulate osteoblastic cells to secrete neutral collagenase, an enzyme thought to be linked to bone matrix turnover. Since recent studies suggest that the calcium/protein kinase-C (PKC) message system is involved in signal transduction stimulated by PTH, we examined the role of these putative second ...
Kolesnick R N - - 1989
Prior studies showed that sphingomyelinase action and the free sphingoid bases inhibited protein kinase C (Kolesnick, R. N., and Clegg, S. (1988) J. Biol. Chem. 263, 6534-6537). The present studies investigated whether sphingomyelinase action also inhibited a biologic process mediated via protein kinase C, phorbol ester-induced differentiation of HL-60 promyelocytic ...
Tran P L - - 1989
The four fluorescent derivatives of TPA--dansylaza-TPA, NBDaza-TPA, and (N)- and (P)-dansylamino-TPA--were synthesized and examined for their ability to induce differentiation in human promyelocytic leukemic HL60 cells. At a concentration of 20 nM, all the derivatives inhibited proliferation and induced 60-80% of the cells to differentiate into macrophage-like cells. Removal of ...
Porfiri E - - 1989
We have studied the metabolism and cellular levels of inositol lipids and their breakdown products, the inositol phosphates and diacylglycerol (DAG), in HL60 human myeloid leukemia cells. Changes in these species during phorbol myristate acetate (PMA)-induced differentiation to a macrophage-like phenotype were quantitated by isotopic labeling techniques. The slow, autonomous ...
Forbes I J - - 1989
In the presence of pyrithione, which was used as a Zn2+ ionophore, Zn2+ (10-100 microM) increased phorbol ester binding by intact B-CLL cells in a dose-dependent fashion. Zn pyrithione increased 2-fold the number of phorbol ester receptors in B-cells (0.74 to 1.4 pmol/10(6) cells), neutrophil polymorphs (0.2 to 0.51 pmol/10(6) ...
Kato M - - 1989
We here show that tetradecanoyl phorbol acetate (TPA) and 1-oleoyl 2-acetyl glycerol (OAG) cause the translocation of diacylglycerol (DG) kinase from the cytosol to the membrane fractions in chick embryo fibroblast (CEF) cells. However, this translocation is not marked in erbB-transformed chick embryo fibroblast (GEV) cells. The activities of phosphatidylinositol ...
Brown A F - - 1989
Quantitative analysis of cell size and shape has shown that the tumour promotor 12-o-tetradecanoylphorbol-13-acetate (TPA) alters one of three parameters of cell shape, dispersion. It has no effect on cell area or elongation. This reflects the fact that TPA causes cells to form long narrow processes extending from the cell ...
Kuter I - - 1989
We have investigated the relationship between collagenase production, cell shape and stimulatory factors in cell culture. In a homogeneous culture of primary rabbit corneal stromal cells, shape change induced by a variety of agents was not effective in stimulating collagenase secretion. Only in the presence of a biologically active cytokine ...
Paulin-Levasseur M - - 1989
Using immunofluorescence and immunoblotting techniques, we have examined the composition of the nuclear lamina in murine plasmacytoma cells, MPC-11, exposed to the phorbol ester TPA as well as in two cell lines devoid of cytoplasmic intermediate filament proteins, the human adrenal cortex carcinoma-derived cells SW-13 and the clone C6-M-D4 derived ...
Wärngård L - - 1989
Two structurally unrelated compounds, 1,1'-(2,2,2-trichloroethylidene) bis(4-chlorobenzene) (DDT) and 12-O-tetradecanoylphorbol-13-acetate (TPA), are both potent inhibitors of cell-cell communication in vitro as well as tumour promoters in vivo. There is evidence that TPA acts via a specific receptor mechanism involving activation of protein kinase C (pkC). The mechanism of action of DDT ...
Nabi Z F - - 1989
Freeze-fracture analysis has shown that treatment of cells with phorbol myristate acetate (PMA) results in a loss of intramembranous particles (IMP) associated with the external leaflet of their plasma membranes. It has also been demonstrated that phorbol esters markedly enhance the sensitivity of tumor targets to natural killer (NK) cells, ...
Balcer-Kubiczek E K - - 1989
C3H/10T1/2 cells were exposed to 2.45-GHz microwaves for 24 h and/or 1.5 Gy of 238-kVp X rays at 3.75 Gy/min. Transformation frequency and cell survival were measured with or without postirradiation addition of the tumor promoter tetradecanoyl-phorbol-13-acetate (TPA) at 0.1 microgram/ml. We previously reported (Carcinogenesis 6,859-864, 1985) an enhancement of ...
Yamada K - - 1989
80 kDa diacylglycerol kinase (DGK) was immunoquantitated in cell homogenates and subcellular fractions. It was extremely abundant in the cytosol of various lymphocytes and comprised, in the highest case, more than 0.2% of the total soluble protein in T cell-enriched pig splenocytes. The lymphocyte membrane contained less than 10% of ...
Nakajima M - - 1989
Using [125I]I-S-145-OH, a radiolabeled derivative of a thromboxane (TX) A2 receptor antagonist, we have studied the expression of the TXA2 receptor in several lines of cultured leukemia cells. Specific binding of the ligand was observed in cells of two human erythroleukemia cell lines, K562 and HEL. However, only negligible binding ...
Unten S - - 1989
Antitumor substances (Fractions VI and VII) prepared from the NaOH extract of pine cone significantly stimulated the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood adherent mononuclear cells, polymorphonuclear cells (PMN), and human promyelocytic leukemic HL-60 cells. In contrast, these fractions did not significantly increase ...
Melton L B - - 1989
This report provides direct evidence that protein kinase C (PKC) is activated in isolated, rigorously accessory cell (AC)-depleted T cells when the T cell antigen recognition complex is stimulated by divalent anti-CD3 monoclonal antibody. Anti-CD3 monoclonal antibody-stimulated PKC activation alone does not, however, directly stimulate T cell proliferation in the ...
Miller D R - - 1989
Carcinogen treatment of normal mouse epidermal cells causes some cells, if cultured under the appropriate conditions, to continue to proliferate instead of terminally differentiate, forming foci at 37 degrees C in medium with a calcium level above 0.1 mM. We have examined these Calcium (Ca)-resistant cells formed in the skin ...
Wärngård L - - 1989
The effects of the pyrethroids flucythrinate, cyfluthrin, bioallethrin and resmethrin on metabolic cooperation between V79 cells were investigated. Addition of flucythrinate to cocultures of 6-thioguanine-resistant and 6-thioguanine-sensitive V79 cells significantly increased the mutant cell recovery, indicating inhibition of intercellular communication. No such effect was observed by the other pyrethroids tested. ...
Hashimoto Y - - 1989
Exposure of HL-60 cells to 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in specific alterations in thymidine (TdR) metabolism. Within 12 h after treatment with 1.62 nM TPA, the reciprocal alteration in the activities of opposing pathways of TdR metabolism observed during normal culture cell growth was reversed. In TPA-treated cells, the activities of ...
Bentley S A - - 1989
Human promyelocytic cells (HL-60) were labeled with 35S-sulfate and either 3H-glucosamine or 3H-serine as precursors. Accumulation of 35S-labeled macromolecules was approximately linear for up to 96 h, with a mean cell:medium ratio of 5.5:1, although activity/10(5) viable cells reached a plateau level after 24 h. Virtually none of the cell-associated ...
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