Application of Cell Cultures to Toxicology

Freshney, Ian

doi:10.1007/978-94-017-0996-5_2

Cited by 22 publications

(23 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…3A and B). To determine whether this growth-inhibitory effect was reversible, a characteristic of cytostatic agents (32), cells were treated with various concentrations of mifepristone for 3 days, trypsinized, and re-plated at low density together with cells that had been pretreated with vehicle. Results in Fig.…”

Section: Resultsmentioning

confidence: 99%

Mifepristone Inhibits Ovarian Cancer Cell GrowthIn vitroandIn vivo

Goyeneche

Carón

Telleria

2007

Clinical Cancer Research

136

View full text Add to dashboard Cite

Purpose: These studies were designed to determine whether the synthetic steroid mifepristone inhibits ovarian cancer growth in vitro and in vivo and the molecular mechanisms involved. Experimental Design: The effect of mifepristone on ovarian cancer cell growth in vitro was studied in ovarian cancer cell lines of different genetic backgrounds (SK-OV-3, Caov-3, OV2008, and IGROV-1). In addition, the growth inhibition capacity of mifepristone on ovarian carcinoma xenografts was tested in nude mice. Results: Mifepristone inhibited ovarian cancer cell proliferation in a dose-and time-dependent manner. The cytostatic effect of mifepristone was confirmed in a clonogenic survival assay and was not linked to loss of viability. Mifepristone blocked DNA synthesis, arrested the cell cycle at the G 1 -S transition, up-regulated cyclin-dependent kinase (cdk) inhibitors p21 cip1 and p27 kip1 , down-regulated transcription factor E2F1, decreased expression of the E2F1-regulated genes cdk1 (cdc2) and cyclin A, and modestly decreased cdk2 and cyclin E levels. The abrupt arrest in cell growth induced by mifepristone correlated with reduced cdk2 activity, increased association of cdk2 with p21 cip1 and p27 kip1 , increased nuclear localization of the cdk inhibitors, and reduced nuclear abundance of cdk2 and cyclin E. In vivo, mifepristone significantly delayed the growth of ovarian carcinoma xenografts in a dose-dependent manner and without apparent toxic effects for the animals. Conclusions: These preclinical studies show that mifepristone is effective as a single agent in vitro and in vivo, inhibiting the growth of human epithelial ovarian cancer cells. Mifepristone markedly reduces cdk2 activity likely due to increased association of cdk2 with the cdk inhibitors p21 cip1 and p27 kip1 and reduced nuclear cdk2/cyclin E complex availability. Acting as a cytostatic agent, mifepristone promises to be of translational significance in ovarian cancer therapeutics.Mifepristone, commonly known as RU486, was first synthesized in the early 1980s and described as a progesterone receptor antagonist (1). The potent antagonism of mifepristone on uterine progesterone receptors led to its clinical application for termination of pregnancy, emergency contraception, luteal phase contraception, and menstrual regulation (2). However, when targeting cells other than uterine cells, the progesterone antagonistic activity of mifepristone is less clear. For instance, in fibroblasts and T47D breast cancer cells, treatment with activators of protein kinase A abrogated the antagonistic activity of mifepristone that instead elicited partial agonistic effects (3,4). In HeLa cells, mifepristone significantly induced progesterone-regulated reporter genes, and this agonistic effect was synergistically enhanced by elevating cyclic AMP or by overexpressing the catalytic subunit of protein kinase A (5). The molecular basis for the mixed agonist/antagonist transcriptional regulation of mifepristone in a cell type -specific manner seems to depend on the ratio...

show abstract

Section: Resultsmentioning

confidence: 99%

Mifepristone Inhibits Ovarian Cancer Cell GrowthIn vitroandIn vivo

Goyeneche

Carón

Telleria

2007

Clinical Cancer Research

136

View full text Add to dashboard Cite

show abstract

“…After incubation (1 and 24 hours), cells were carefully washed with PBS and incubated with the fluorescent probes. The cytotoxicity assay was carried out through direct counting of the cells using the trypan blue exclusion method (13).…”

Section: Venom Treatmentmentioning

confidence: 99%

Cytoskeleton, endoplasmic reticulum and nucleus alterations in CHO-K1 cell line after Crotalus durissus terrificus (South American rattlesnake) venom treatment

Tamieti¹,

DaMatta²,

Cogo³

et al. 2007

J. Venom. Anim. Toxins incl. Trop. Dis

View full text Add to dashboard Cite

Snake venoms are toxic to a variety of cell types. However, the intracellular damages and the cell death fate induced by venom are unclear. In the present work, the action of the South American rattlesnake Crotalus durissus terrificus venom on CHO-K1 cell line was analyzed. The cells CHO-K1 were incubated with C. d. terrificus venom (10, 50 and 100g/ml) for 1 and 24 hours, and structural alterations of actin filaments, endoplasmic reticulum and nucleus were assessed using specific fluorescent probes and agarose gel electrophoresis for DNA fragmentation. Significant structural changes were observed in all analyzed structures. DNA fragmentation was detected suggesting that, at the concentrations used, the venom induced apoptosis.

show abstract

“…The in vitro culture of cells is an important tool for studying the cytotoxic activity of substances with potential therapeutic activity (Freshney, 2001).…”

Section: Discussionmentioning

confidence: 99%

Phytochemical investigation, antinociceptive activity and cytotoxicity of crude extracts of Calea uniflora Less.

Rodrigues-Torres¹,

Machado²,

Ramos³

et al. 2016

J. Med. Plants Res.

View full text Add to dashboard Cite

Calea uniflora Less. is a medicinal plant used in the treatment of inflammation and haematomas in southern Brazil. The aim of this study was to investigate the antinociceptive effects and cytotoxicity of C. uniflora. Regarding phytochemical evaluation, the crude extracts of plant were analysed by highperformance liquid chromatography (HPLC). Antinociceptive activities utilised models on chemical and thermal stimuli in vivo. To evaluate cytotoxic activity, the 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide method (MTT test) was utilised in vitro. Phytochemical analyses verified the presence of flavonoids and sesquiterpenes. Regarding antinociceptive activity, the models produced significant results that correspond to chemical at doses of 100 and 300 mg/kg of the crude extract as compared to the control groups, respectively. The rota rod model showed satisfactory results, since the extract did not cause motor incoordination and sedation in this experiment. In the in vitro cytotoxic tests, the crude extracts and ethyl acetate and butanolic fractions produced IC 50 values greater than 58 µg/mL with the HaCaT lineage and 48 µg/mL with the B16-F1 lineage; thus, these values did not produce cytotoxic effects. According to these results, flavonoids and alkaloids were found in C. uniflora extracts. Pharmacological activities were also detected as reported by the local population that uses this plant in traditional medicine, especially antinociceptive and cytotoxic activities.

show abstract

Application of Cell Cultures to Toxicology

Cited by 22 publications

References 10 publications

Mifepristone Inhibits Ovarian Cancer Cell GrowthIn vitroandIn vivo

Mifepristone Inhibits Ovarian Cancer Cell GrowthIn vitroandIn vivo

Cytoskeleton, endoplasmic reticulum and nucleus alterations in CHO-K1 cell line after Crotalus durissus terrificus (South American rattlesnake) venom treatment

Phytochemical investigation, antinociceptive activity and cytotoxicity of crude extracts of Calea uniflora Less.

Contact Info

Product

Resources

About