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Giese G - - 1990
Vimentin expression throughout the cell cycle has been analyzed at the single-cell level in asynchronously growing MPC-11 cells using multiparameter flow cytometry. We have previously shown that these cells normally lack detectable amounts of intermediate filament proteins. In the presence of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), cell proliferation ceases and ...
Etscheid B G - - 1990
Mitogenic stimulation of Na(+)-H+ exchange activity, as defined by the level of 5-(N,N-hexamethylene)amiloride (HMA)-sensitive Na+ influx, was compared in WI-38 and SV40 virus-transformed WI-38 fibroblasts. Serum or bradykinin dramatically stimulated HMA-sensitive Na+ influx in WI-38 cells, whereas in SV40-transformed WI-38 cells, serum, but not bradykinin, produced a large increase in ...
Kuratsune H - - 1990
We have assessed whether tyrosine protein kinase (TPK) is involved in B cell differentiation. In vitro phosphorylation of an endogenous substrate in B cell leukemias showed that leukemic B cells at different stages of differentiation had specific endogenous substrates in tyrosine phosphorylation as well as distinct TPK activity. To clarify ...
Kong Z L - - 1990
A human macrophagelike cell line which grows in serum-free medium was established from a histiocytic lymphoma cell line, U-937. U-937 cells failed to differentiate into macrophagelike cells in serum-free medium plus 12-O-tetradecanoyl phorbol 13-acetate (TPA). Fibronectin and albumin in serum were necessary for differentiation of U-937 cells into macrophagelike cells ...
Robertson F M - - 1990
The ability of murine epidermal cells to produce intracellular hydrogen peroxide was analyzed by flow cytometry and the measurement of 2',7'- dichlorofluorescin (DCFH) oxidation. Epidermal cells isolated from acetone-treated CD-1 mice for 24 h were relatively homogeneous in cell size and density and oxidized low levels of DCFH. However, following ...
Koehler L - - 1990
The molecular mechanism of the glucocorticoid-induced inhibition of prostanoid synthesis was investigated in human monoblastoid U937 tumor cells and phorbol ester (TPA)-differentiated U937 cells. Prostanoid synthesis was inhibited in TPA-differentiated U937 cells by glucocorticoids such as dexamethasone and prednisolone, whereas aldosterone and progesterone showed no inhibitory effect. None of these ...
Yamadori I - - 1990
Disruption of intercellular communication (IC) by tumor promoters has been implicated as one of the major events in the promotion process. We studied the effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) on IC in relation to colony formation (CF) in a coculture system of mouse epidermal JB6 cells, including unpromotable, promotable, and transformed ...
Mamune-Sato R - - 1990
The human leukemic cell line KU-812-F is known to differentiate into mature basophil-like cells under serum-free culture conditions. In the present study, the activity of histidine decarboxylase (HDC), a histamine-forming enzyme, in KU-812-F cells was found to be high, ranging from 10 to 57 pmol/min/mg protein. The great variation in ...
Harris E L - - 1990
Vascular smooth muscle cells cultured from spontaneously hypertensive (SHR), New Zealand genetically hypertensive (GH) rat strains and their control strains (Wistar-Kyoto (WKY) and normal Wistar (N) rats) were compared for mitogenic responses [( 3H]-thymidine incorporation) to angiotensin II (AII), fetal calf serum (FCS), and the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA). SHR ...
Koga M - - 1990
A previous study from this laboratory (Koga et al., Cancer Res., 48: 2734-2739, 1988) demonstrated that the growth inhibitory effect of 1,25-dihydroxyvitamin D3 in human breast cancer cells in vitro was associated with a decline in the concentration of epidermal growth factor receptor (EGF-R). In the present study experiments were ...
Nori M - - 1990
To study the relationship between oncogenesis by v-src and normal cellular signalling pathways, we determined the effects of v-src on 3T3-TNR9 cells, a Swiss 3T3 variant which does not respond mitogenically to tumor promoters such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA). We found that src was unable to transform these variant cells, whether ...
Glasø M - - 1990
Ultrastructural morphometric characteristics of basal keratinocytes in hairless mouse epidermis were analyzed statistically. The following variables were assessed: (i) low versus physiological osmolality during fixation, (ii) alterations induced by a 2-stage carcinogenesis regimen using DMBA and TPA, (iii) criteria for a cell being dark versus being clear, (iv) inter-observer variation. ...
Robertson F M - - 1990
Ornithine decarboxylase (ODC), the initial enzyme in the polyamine biosynthetic pathway, has been used as a marker for the hyperplasia that occurs following exposure of mouse epidermis to the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Using flow cytometry in combination with polyclonal antibodies to ODC, we examined the levels of ODC-associated immunoreactive ...
Hsu S M - - 1990
Two Hodgkin's Reed-Sternberg cell (H-RS) lines, HDLM-1 and KM-H2, have phenotypes and functional properties very similar to those of H-RS cells in tissues. These two types of cells were induced to differentiate with a combination of phorbol ester, retinoic acid, and extracellular matrix. The induced cells displayed the morphology of ...
Burrous B A - - 1990
The present study is a detailed kinetic analysis of the synthesis, release and multimerization of fibronectin (FN) in normal and tumor promoter-treated human lung fibroblasts. Pulse/chase and surface labeling experiments were performed to follow the fate of both newly synthesized and preexisting cell-surface FN over time. The majority of FN ...
Dean N M - - 1990
Proliferation in rat liver T51B cells has previously been shown to be initiated by the tyrosine-kinase activator epidermal growth factor. We have found that T51B cells also contain angiotensin II receptors, and, as the transforming mas oncogene has been identified as a functional angiotensin receptor [Jackson, Blair, Marshall, Goedert & ...
Martin T W - - 1990
The mechanism of phosphatidylcholine (PC) degradation stimulated by phorbol myristate acetate (PMA) was investigated in bovine pulmonary artery endothelial cells prelabeled with [methyl-3H]choline ([3H]choline) or [9,10-3H]myristic acid ([3H]myristic acid). Both labels were selectively incorporated into PC, and addition of PMA stimulated comparable losses of 3H from PC in cells prelabeled ...
Shibanuma M - - 1990
Treatment of quiescent Balb/3T3 clone A31-1-1 cells with 0.1-0.2 mM H2O2 in the presence of 1 microM insulin induced DNA synthesis 20-24 h later at almost the same level as that in cells treated with 10% serum. Treatment with 0.1-0.2 mM H2O2 alone did not induce DNA synthesis and was ...
Bikfalvi A - - 1990
The human omentum contains a potent, not yet identified angiogenic activity. The omentum is very vascularized. Therefore, we investigated whether human omental microvascular endothelial cells (HOME cells) express the angiogenic peptide basic fibroblast growth factor (bFGF). Cytosol prepared from HOME cells stimulated DNA synthesis in bovine epithelial lens cells (BEL ...
Maleci A - - 1990
The mechanisms by which lymphokine-activated killer (LAK) cells exert their cytotoxic effects are not well understood. This study demonstrates that phorbol ester pretreatment of a LAK cell-sensitive glioma cell line (SNB-19) induced a significant decrease in the susceptibility of cells to LAK cell-mediated lysis. This effect was produced by low ...
Jalava A M - - 1990
SH-SY5Y human neuroblastoma cells can be induced to differentiate to mature ganglion cells when treated with the phorbol ester tetradecanoylphorbol acetate (TPA). Bryostatins are a new class of protein kinase C activators that are structurally unrelated to phorbol esters. This paper describes the effects of bryostatins 1 and 2 on ...
Seckinger P - - 1990
Lipopolysaccharide (LPS) induces cell-associated interleukin 1 (IL 1) production in the human promonocytic cell line U937. Demonstration of cell-associated IL 1 activity was based on the ability of LPS-treated U937 cells, subsequently fixed with paraformaldehyde, to stimulate thymocyte proliferation in the presence of phytohemagglutinin. Like soluble IL 1 (sIL 1), ...
Aguanno S - - 1990
The effect of 12-O-tetradecanoyl phorbol-13-acetate (TPA) on proliferation and differentiation of the human embryonal rhabdomyosarcoma cell line RD was investigated. The proliferation of RD cells is drastically and reversibly inhibited by 100 nM TPA. The effect is evident after 24 h of treatment and is maximal after 50-70 h. The ...
Plummer H K HK - - 1990
The objective of the present work was to determine whether a short-term perturbation of cells by 12-O-tetradecanoyl phorbol-13-acetate (TPA) treatment caused shape changes identical to those found in oncogenic transformation. A cell line derived from the rat respiratory tract epithelium, 1000 W, was used, in which shape changes had been ...
Järvinen M - - 1990
The effects of differentiation-modulating drugs were studied on the expression of intermediate filaments (IFs) in the human K562 erythroleukemic cell line. The untreated cells contained typical cytoplasmic coiling bundles, positive for both vimentin and cytokeratin as judged by indirect immunofluorescence microscopy with monoclonal antibodies (Mabs). Some of the cells also ...
Sandvig K - - 1990
Cytochalasin D was found to reduce the endocytosis of ricin and the fluid phase markers [14C]sucrose and Lucifer Yellow in Vero cells without reducing the uptake of transferrin. The number of coated pits at the plasma membrane was not affected by the treatment. Cytochalasin D also reduced the endocytosis of ...
Long M W - - 1990
Induction of human erythroleukemia (HEL) cells with nanomolar tumor-promoting phorbol myristate acetate (PMA) diesters results in the synchronous acquisition of multiple markers of the megakaryocyte phenotype. Induced cells markedly increase their content of cytoplasm and show features of morphological maturation. At the ultrastructural level, PMA-treated cells show increases in cytoplasm, ...
Schütze S - - 1990
We have investigated the changes in protein kinase C (PKC) activity after treatment of several cell lines with TNF. Binding studies with [3H]phorbol dibutyrate (PBt2) on whole cells revealed rapid and transient activation of PKC in Jurkat, K562, and U937 cells with a maximum of phorbol ester binding at 6 ...
Hass R - - 1990
Significant morphological and functional changes were observed when human monoblastoid U937 tumor cells growing in suspension were induced by the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) for 72 h to differentiate along the monocyte/macrophage pathway. These include adherence of the cells to each other and to the substratum, alterations in cell-surface antigen ...
Beckwith M - - 1990
The activation, growth, and differentiation of three B-cell- and one non-B-cell-derived human lymphoma cell lines were examined after treatment with protein kinase C-activating phorbol esters. Treatment with these agents resulted in early activation events similar to those observed in normal B cells. However, in contrast to their growth-promoting effect on ...
Ramachandran C K - - 1990
The activity of neutral sphingomyelinase (EC 3.1.4.12) in a plasma membrane enriched fraction was found to be increased in dexamethasone treated cells. The elevation of sphingomyelinase activity was blocked by cycloheximide indicating that protein synthesis was required for the steroid action. Ceramidase (EC3.5.1.23) activity was unaffected by the dexamethasone treatment. ...
Baker R C - - 1990
Ethanol was examined for its effects on zymosan phagocytosis and synthesis of platelet-activating factor (PAF) using a clonal macrophage cell line. PAF, identified as 1-O-alkyl-2-acetyl-sn-glycerol-3-phosphocholine, is a biologically active ether phospholipid produced by various cells types. PAF also activates a variety of inflammatory cells including the cells which produce PAF. ...
Järvinen M - - 1990
The expression of vimentin intermediate filaments (IFs) was studied in a human erythroleukemia cell line (HEL), exposed to a variety of differentiation-inducing agents. These cells grow normally in suspension and show a heterogenous expression of vimentin immunoreactivity. In the presence of retinoic acid the fibrillar vimentin immunoreactivity diminished rapidly, while ...
Takasu N - - 1990
We studied the effects of epidermal growth factor (EGF), 12-O-tetradecanoylphorbol-13-acetate (TPA), and 1-oleoyl-2-acetyl-glycerol (OAG) on cytoplasmic pH (pHi) and cell growth in cultured porcine thyroid cells. pHi was measured using 2',7'-bis(2-carboxyethyl-5,6-carboxyfluorescein (BCECF), an internalized fluorescent pH indicator. EGF, TPA, and OAG alkalinized the thyroid cells and stimulated their growth. These ...
Baron P L - - 1990
This study was undertaken to determine whether the phorbol diester, phorbol 12-myristate 13-acetate (PMA), causes differentiation of the human colon carcinoma cell line, SW 48. Under routine growth conditions, the cells are round, have a high nuclear-to-cytoplasmic ratio, and lack cytoplasmic vacuoles. After treatment for 1 hour with 100 nmol/L ...
Aussel C - - 1990
Activation of Jurkat T cells with either phytohemagglutinin (PHA), CD3 or CD2 monoclonal antibodies (mAbs) induces the production of diacylglycerol (DAG) from two different sources. Activation of the phosphatidylinositide cycle in activated T cells is a well-known source of the second messengers DAG and inositol triphosphate (IP3). The present report ...
Zeng M B - - 1990
The effect of a phorbol ester (TPA) on myogenesis of urodelian embryo has been investigated. Presumptive somites were extirpated from mid-neurula, the stage when they have already attained certain degree of determination. The explants were treated with TPA (10 ng/ml in Steinberg solution with the addition of 10% Leibovitz's L-15) ...
Opas M - - 1990
Chick retinal pigmented epithelial (RPE) cells grown in vitro on basement membrane matrices from the Engelbreth-Holm-Swarm tumour (BM-matrigel) do not spread, and they maintain their differentiated phenotype, most notably the heavy pigmentation. Maintenance of the differentiated phenotype by RPE cells on BM-matrigel is promoted not only by the biochemical composition ...
Schuster G S - - 1990
N-nitrosonornicotine (NNN), a significant nitrosamine component of tobacco binds to and is taken up by cells prior to its activation by intracellular enzymes. A variety of factors may affect the binding of substances to a cell including the cell type, medium composition and the cell membrane lipid composition. This study ...
Kimura E - - 1990
Cells of the Y-1 corticoadrenal line are: (a) functional, (b) cell cycle-arrested by adrenocorticotropic hormone (ACTH), (c) tumorigenic, and (d) c-Ki-ras overexpressing. We here report that the phorbol ester phorbol 12-myristate 13-acetate (PMA) mimics all ACTH-specific effects in Y-1 cells, namely: (a) steroid-ogenesis stimulation, (b) cell cycle block, and (c) ...
Simon J P - - 1990
The prohormone chromogranin A is the major soluble component of secretory granules in chromaffin cells of adrenal medulla and in many other different endocrine cell types. The proteolytic processing of chromogranin A was studied in cultured bovine chromaffin cells using [35S]methionine to label proteins and a specific antibody to immunoprecipitate ...
Miki H - - 1990
We studied gap junctional intercellular communication (IC) in various clones of mouse epidermal JB6 cells and the effect of the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA) on such communication. JB6 clones used included nonpromotable, promotable, and transformed clones, representing a spectrum in susceptibility to transformation from nontransformed, to initiated (postinitiated), to transformed ...
Jänicke R - - 1990
Several lines of evidence point to an activation mechanism of monocytes/macrophages by tumor cells. In this study we present data for distinct surface structures on K562 and Jurkat cells to directly induce TNF-mRNA expression and TNF production by human peripheral blood monocytes. Northern analysis showed that incubation of monocytes with ...
Nishikawa M - - 1990
To evaluate the molecular basis for susceptibility of the cell differentiation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), we examined biochemical activities and expression of subspecies of protein kinase C from HL-60 cells that are susceptible to differentiation induced by TPA and HL-60R cells, HL-60 variant cells that are resistant to such induction. ...
Hass R - - 1990
Incubation of the human monoblastoid tumor cell line U937 with 5 x 10(-9) M 12-O-tetradecanoylphorbol-13-acetate (TPA) for 3 days was associated with marked morphological and functional changes including adherence of the cells and cessation of proliferation. While growth arrest and the viability of the cells were not influenced, the TPA-induced ...
Kucharz E J - - 1990
Human peripheral blood T cells or continuous T cell lines were treated with phorbol myristate (PMA), a direct protein kinase C activator. The effect of isoniazid on PMA-treated cells was investigated. It was found that low doses of isoniazid augmented proliferation of T cells treated with PMA or stimulated with ...
Claudette P - - 1990
Phosphatidylserine has been implicated both in the regulation of protein kinase C activity and in the regulation of T lymphocyte activation in vitro and in vivo. Treatment of Jurkat T cells with PS, results in a strong decrease of Interleukin-2 synthesis. Arachidonoyl-diacylglycerol production and Ca++ mobilization due to the increase ...
Girard P R - - 1990
A potential role of the protein kinase C (PKC) system in differentiation of human neuroblastoma cell line LA-N-5 was investigated. It was found that neurite outgrowth induced by 12-O-tetradecanoylphorbol 13-acetate (TPA, 81 nM) was associated with a down-regulation of PKC as determined independently by immunocytochemistry, immunoblot, and enzyme activity assay. ...
Hooper W C - - 1990
The TE 671 medulloblastoma cell line was induced by phorbol-12-myristate-13-acetate (PMA) to resemble neuronal cells by both morphological and immunohistochemical criteria. Five days following PMA treatment at a concentration of 10 ng/ml, the cells acquired long cellular processes and cell growth was markedly inhibited. Immunohistochemically, PMA-treated cells stained intensely for ...
Neumark T - - 1990
Human interferon-alpha (Hu-IFN alpha) and phorbol myristate acetate (PMA), a direct activator of protein kinase C (PK-C), induce the translocation of protein kinase C from the cytosol to the membrane fraction. By the use of transmission (TEM) and scanning (SEM) electron microscopy we have shown that treatment of human amniotic ...
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