scholarly journals Effects of Ursolic Acid and its Analogues on Soybean 15-Lipoxygenase Activity and the Proliferation Rate of A human Gastric Tumour Cell Line

1994 ◽  
Vol 3 (3) ◽  
pp. 181-184 ◽  
Author(s):  
D. Es-Saady ◽  
A. Najid ◽  
A. Simon ◽  
Y. Denizot ◽  
A. J. Chulia ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Line ◽  
Ursolic Acid ◽  
Oleanolic Acid ◽  
Tumour Cell ◽  
Lipoxygenase Activity ◽  
Tumour Cell Line ◽  
Dependent Manner ◽  
Gastric Tumour ◽  
Methyl Ursolate

The authors have previously isolated and purified ursolic acid from heather flowers (Calluna vulgarts). This terpene was found to inhibit HL-60 leukaemic cell proliferation and arachidonic acid oxidative metabolism in various cell species. The effects of ursolic acid and its analogues on soybean 15-lipoxygenase activity and on the proliferation of a human gastric tumour cell line (HGT), have been assessed. These triterpenes inhibited soybean 15-lipoxygenase at its optimal activity (pH 9). The proliferation ofHGT was decreased in a dose-dependent manner. At 20 μM the rank order is: ursolic acid > uvaol > oleanolic acid > methyl ursolate. The carboxylic group at the C28position of ursolic acid appears to be implicated in the inhibition of both lipoxygenase activity and cell proliferation. Thus methylation of this group decreases these two inhibitory properties. Oleanolic acid, which differs by the position of one methyl group (C20instead of C19) is less inhibitory than ursolic acid. The lipophilicity of the terpene is also implicated since uvaol appears to be more inhibitory than methyl ursolate.

Interleukin-1β induces nitric oxide production by a mouse pituitary tumour cell line (AtT20/D16)

1993 ◽  
Vol 138 (3) ◽  
pp. 429-435 ◽  
Author(s):  
K. Ohta ◽  
Y. Hirata ◽  
T. Imai ◽  
F. Marumo
Keyword(s):  
Cell Line ◽  
Tumour Cell ◽  
Pituitary Tumour ◽  
No Synthase ◽  
Tumour Cell Line ◽  
Dependent Manner ◽  
Mouse Pituitary ◽  
Dose Dependent ◽  
Inducible Nos ◽  
Acth Release

ABSTRACT To elucidate whether anterior pituitary cells express the nitric oxide (NO) synthase gene, we studied the synthesis of NO and the expression of NO synthase (NOS) mRNA by a mouse pituitary tumour cell line (AtT20/D16). Interleukin-1β (IL-1β) stimulated production of NO2−/NO3− (NOx) in a time-dependent manner and both NOx and cyclic GMP formation were stimulated in a dose-dependent manner by IL-1β. IL-1β-induced NOx production and intracellular cyclic GMP formation were similarly blocked by an NO synthase inhibitor, NG-monomethyl-l-arginine (LNMMA), whose effect was reversed by l-arginine, but not by d-arginine. Dexamethasone inhibited IL-1β-induced NOx production in a dose-dependent manner. A calmodulin inhibitor (W-7) showed no effect on IL-1β-induced NOx production, whereas cycloheximide and the actinomycin D completely inhibited NOx production. Northern blot analysis using cDNA for mouse macrophage-inducible NOS as a probe revealed the expression of inducible NOS mRNA in the cells only after exposure to IL-1β. Although IL-1β stimulated ACTH release from tumour cells, LNMMA failed to affect ACTH release stimulated by IL-1β. These results demonstrate for the first time that a pituitary tumour cell line (AtT20/D16) possesses cytokine-inducible and Ca2+/calmodulin-independent NOS, although NO may not be involved in ACTH release. Journal of Endocrinology (1993) 138, 429–435

scholarly journals A possible relation between dietary zinc and cAMP in the regulation of tumour cell proliferation in the rat

1988 ◽  
Vol 59 (3) ◽  
pp. 437-442 ◽  
Author(s):  
Noel S. Skeef ◽  
John R. Duncan
Keyword(s):  
Cell Proliferation ◽  
Cell Division ◽  
Cell Line ◽  
Tumour Cell ◽  
Tumour Growth ◽  
Zn Deficiency ◽  
Regenerating Liver ◽  
Small Reduction ◽  
Dietary Zinc ◽  
Camp Concentration

1. The possibility of an effect of zinc on the rate of tumour cell division, mediated through a regulation of cellular cAMP concentration, was investigated in the present study in rats.2. Dietary Zn deficiency (< 1·5 mg Zn/kg) but not Zn excess (500 mg Zn/kg) resulted in an increased cAMP concentration in transplanted hepatoma cells. Neither treatment had any effect on the cAMP concentration in regenerating liver or normal resting liver. Both the deficient and excess Zn diets resulted in a small reduction in tumour growth (not statistically significant).3. The results seem to indicate that the relation investigated in the present study does not apply in the cell line used.

Epinephrine Stimulates Cell Proliferation and Induces Chemoresistance in Myeloma Cells through the β-Adrenoreceptor in vitro

2017 ◽  
Vol 138 (2) ◽  
pp. 103-110 ◽  
Author(s):  
Yang Liu ◽  
Xiaochen Yu ◽  
Junling Zhuang
Keyword(s):  
Cell Proliferation ◽  
Cell Growth ◽  
Cell Line ◽  
Receptor Subtype ◽  
Dependent Manner ◽  
Myeloma Cells ◽  
U266 Cell ◽  
Β Receptor ◽  
U266 Cell Line

Objectives: To explore the effect of the β-adrenoreceptor signaling pathway on myeloma cells. Methods: The myeloma U266 cell line was treated with epinephrine and propranolol. Cell proliferation was analyzed by MTS assay. Apoptosis was detected by flow cytometry. The β-receptor subtype and the key enzyme of epinephrine were identified by reverse transcription polymerase chain reaction (RT-PCR). Results: Epinephrine (5-50 μM) promoted U266 cell growth in a dose-dependent manner and neutralized the inhibition effect of bortezomib (25 and 50 ng/mL) in vitro. Cell proliferation was inhibited by a β-receptor antagonist, propranolol, at a concentration of 50-200 μM. The proportions of early and late apoptotic cells were enhanced after treatment with propranolol. The expression of caspase 3/7, 8, and 9 was elevated in propranolol-treated myeloma cells. Both β1- and β2-adrenoceptor mRNAs were expressed in the U266 cell line. Key enzymes dopamine hydroxylase and tyrosinehydroxylase were identified in myeloma cells. Conclusions: Our results reveal that epinephrine stimulates myeloma cell growth in vitro while the β-blocker propranolol has an antiproliferative effect, indicating that stress hormones may trigger the progression of myeloma.

Antibodies in the sera of patients with bronchogenic carcinoma that react with antigen from a tumour cell line

1981 ◽  
Vol 12 (1) ◽  
pp. 5-10 ◽  
Author(s):  
Barbara S. Kelly ◽  
Ulrike Stredulinsky ◽  
Joan Vanden Hoek ◽  
Julia G. Levy
Keyword(s):  
Cell Line ◽  
Tumour Cell ◽  
Bronchogenic Carcinoma ◽  
Tumour Cell Line

289. Comparison of lymphocyte subsets and function in the rat and mouse testis

2005 ◽  
Vol 17 (9) ◽  
pp. 122 ◽  
Author(s):  
D. Aridi ◽  
D. Pellicci ◽  
P. Hutchinson ◽  
M. P. Hedger
Keyword(s):  
T Cells ◽  
Cell Line ◽  
Tumour Cell ◽  
Flow Cytometric Analysis ◽  
Nkt Cells ◽  
Mouse Testis ◽  
Tumour Cell Line ◽  
Rat Testis ◽  
Flow Cytometric ◽  
Rats And Mice

Testicular leukocytes are assumed to be involved in immunological surveillance against infection and tumours as well as regulation of local immune responses. They are implicated in mechanisms that make the testis a successful site for tissue transplantation in both rats and mice. Our previous studies using multi-colour fluorescence flow cytometric analysis to examine isolated testicular leukocytes in the rat testis have established the existence of a significant population of predominantly CD8+ T cells and a comparable number of lymphocytes expressing natural killer (NK) cell markers (NK and NKT cells). The functional activity of these testicular NK and NKT cells subsequently has been confirmed by a standard flow cytometric cytotoxicity assay using an NK-sensitive tumour cell line (YAC-1) and an NKT-sensitive tumour cell line (U937). Similar analyses of mouse testicular leukocytes have shown a slightly different pattern. The data indicate that mouse testicular lymphocytes comprise T cells, NK cells, and NKT cells, similar to the rat testis. However, while the apparent numerical densities of T cells in rat and mouse testes were similar, the numbers of NK and NKT cells were considerably lower in the mouse. Mouse testicular NKT cells were positive for staining with the tetramer CD1d/αGC, which is used to identify classical NKT cells, whereas rat NKT cells did not stain for this marker. Moreover, the CD8/CD4 T cell ratio in the mouse testis displayed a skewing towards the CD4+ subset. These data highlight the possibility that the immunological environment, and hence the course of immunological events, might be quite different in the testes of the two species. The reasons for these differences are not clear, however they should be taken into account when considering studies of testicular immune processes. Finally, comparative studies of immunological process in the testes of rats and mice may be very informative.

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