Optimization and prevalidation of the in vitro ERα CALUX method to test estrogenic and antiestrogenic activity of compounds

Burg, Bart van der; Winter, Roos; Weimer, Marc; Berckmans, Pascale; Suzuki, Go; Gijsbers, Linda; Jonas, A.; Linden, Sander van der; Witters, Hilda; Aarts, J.M.M.J.G.

doi:10.1016/j.reprotox.2010.04.007

Cited by 80 publications

(45 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For determination of full dose-response curves of the test compounds (agonistic activity), CALUX ® cells (van der Burg et al, 2010) were seeded in 96 well plates in assay medium (DMEM/ F12 medium with charcoal stripped serum and supplemented with non-essential amino-acids) at 37°C and 5% CO2. After 24 h the cells were exposed in triplicate for another 24 h with dilution series of the pure compounds (ZEN, α-and β-ZAL, α-and β-ZEL: 0.05 pM -0.5 μM; DMSO: 0.1% and E2: highest concentration 0.1 nM as reference compound).…”

Section: Erα Chemical Activated Luciferase Reporter Gene Assay (Caluxmentioning

confidence: 99%

Hazard assessment through hybrid in vitro / in silico approach: The case of zearalenone

Ehrlich

2015

ALTEX

View full text Add to dashboard Cite

SummaryWithin the framework of reduction, refinement and replacement of animal experiments, new approaches for identification and characterization of chemical hazards have been developed. Grouping and read-across has been promoted as a most promising alternative approach. It uses existing toxicological information on a group of chemicals to make predictions on the toxicity of uncharacterized ones. In the present work, the feasibility of applying in vitro and in silico techniques to group chemicals for read-across was studied using the food mycotoxin zearalenone (ZEN) and metabolites as a case study. ZEN and its reduced metabolites are known to act through activation of the estrogen receptor α (ERα). The ranking of their estrogenic potencies appeared highly conserved across test systems including binding, in vitro and in vivo assays. This data suggests that activation of ERα may play a role in the molecular initiating event (MIE) and be predictive of adverse effects, and it provides the rationale to model receptor-binding for hazard identification. The investigation of receptor-ligand interactions through docking simulation proved to accurately rank estrogenic potencies of ZEN and reduced metabolites, showing the suitability of the model to address estrogenic potency for this group of compounds. Therefore, the model was further applied to biologically uncharacterized, commercially unavailable, oxidized ZEN metabolites (6α-, 6β-, 8α-, 8β-, 13-and 15-OH-ZEN). Except for 15-OH-ZEN, the data indicate that in general, the oxidized metabolites would be considered of lower estrogenic concern than ZEN and reduced metabolites.

show abstract

Section: Erα Chemical Activated Luciferase Reporter Gene Assay (Caluxmentioning

confidence: 99%

Hazard assessment through hybrid in vitro / in silico approach: The case of zearalenone

Ehrlich

2015

ALTEX

View full text Add to dashboard Cite

show abstract

“…At the individual test level negative scores were much more frequent, again showing specificity or responses at the thresholds set. In addition, the ERalpha-and AR CALUX test have already been shown to give negative results with all negative controls that were included in validation panels of chemicals selected by ECVAM [7,8] and in the case of the ERalpha CALUX, the OECD [10].…”

Section: Performance Of Individual Assays and Plausibility Of Responsesmentioning

confidence: 99%

“…An important element in our approach was to start with the use of assays that are well underway of being accepted as alternatives to animal experiments, and build up the screening battery from there. This involved the use of receptor based reporter gene assays, such as CALUX ® assays for androgenic and estrogenic compounds that are evaluated in an ECVAM/OECD guided validation effort [6][7][8][9]. We expect that inclusion of validated tests in the core of a screening battery can pave the way for a growing platform to which new mechanism-based assays can be included when knowledge increases, possibly even without going through the entire process of time consuming validation, because the basic technology for each assay is the same.…”

Section: Introductionmentioning

confidence: 99%

A high throughput screening system for predicting chemically-induced reproductive organ deformities

Burg

Pieterse

Buist³

et al. 2015

Reproductive Toxicology

Self Cite

View full text Add to dashboard Cite

“…In selecting tests to be included in the battery, methods were preferred that were either validated or in the process of being validated, including the EST test [33], the zebrafish embryo test [34], and reporter gene assays for estrogens [35,36] and androgens [37]. The ERalpha-and AR CALUX assay already were prevalidated in the context of the ReProTect FP6 program, and subsequently have been this issue to EURL-ECVAM and OECD to allow formal validation, and regulatory acceptance [35,36,38,39]. Since our battery of tests of reporter gene assays is very comparable to these latter tests, the validated tests may be used as "validation anchors" in a screening battery, i.e.…”

Section: Validationmentioning

confidence: 99%

The ChemScreen project to design a pragmatic alternative approach to predict reproductive toxicity of chemicals

Burg

Wedebye

Dietrich

et al. 2015

Reproductive Toxicology

Self Cite

View full text Add to dashboard Cite

a b s t r a c tThere is a great need for rapid testing strategies for reproductive toxicity testing, avoiding animal use. The EU Framework program 7 project ChemScreen aimed to fill this gap in a pragmatic manner preferably using validated existing tools and place them in an innovative alternative testing strategy. In our approach we combined knowledge on critical processes affected by reproductive toxicants with knowledge on the mechanistic basis of such effects. We used in silico methods for prescreening chemicals for relevant toxic effects aiming at reduced testing needs. For those chemicals that need testing we have set up an in vitro screening panel that includes mechanistic high throughput methods and lower throughput assays that measure more integrative endpoints. In silico pharmacokinetic modules were developed for rapid exposure predictions via diverse exposure routes. These modules to match in vitro and in vivo exposure levels greatly improved predictivity of the in vitro tests. As a further step, we have generated examples how to predict reproductive toxicity of chemicals using available data. We have executed formal validations of panel constituents and also used more innovative manners to validate the test panel using mechanistic approaches. We are actively engaged in promoting regulatory acceptance of the tools developed as an essential step towards practical application, including case studies for read-across purposes. With this approach, a significant saving in animal use and associated costs seems very feasible.

show abstract

Optimization and prevalidation of the in vitro ERα CALUX method to test estrogenic and antiestrogenic activity of compounds

Cited by 80 publications

References 24 publications

Hazard assessment through hybrid in vitro / in silico approach: The case of zearalenone

Hazard assessment through hybrid in vitro / in silico approach: The case of zearalenone

A high throughput screening system for predicting chemically-induced reproductive organ deformities

The ChemScreen project to design a pragmatic alternative approach to predict reproductive toxicity of chemicals

Contact Info

Product

Resources

About