The Belgian Virtual Tumorbank: A Tool for Translational Cancer Research.

Biobanks play a critical role in cancer research by providing high quality biological samples for research. However, the availability of tumor samples in single research institutions is often limited, especially for rare cancers. In order to facilitate the search for samples scattered among different Belgian institutions, a nationwide virtual tumorbank project was launched and is operational since February 2012.

Maternal diet during pregnancy and micronuclei frequency in peripheral blood T lymphocytes in mothers and newborns (Rhea cohort, Crete).

Purpose: The study assessed whether diet and adherence to cancer prevention guidelines during pregnancy were associated with micronucleus (MN) frequency in mothers and newborns. MN is biomarkers of early genetic effects that have been associated with cancer risk in adults.

Methods: A total of 188 mothers and 200 newborns from the Rhea cohort (Greece) were included in the study.

Vitamin D insufficient levels during pregnancy and micronuclei frequency in peripheral blood T lymphocytes mothers and newborns (Rhea cohort, Crete).

Background & Aims: Vitamin D deficiency is common among pregnant women and may be associated with several adverse health outcomes including cancer. Micronuclei frequency is a biomarker of early genetic effects and has been used to examine the association between genotoxic exposures and cancer. We examined maternal vitamin D levels during pregnancy in associations with micronuclei frequency in maternal blood and in cord blood.

Outdoor air pollution exposures and micronuclei frequencies in lymphocytes from pregnant women and newborns in Crete, Greece (Rhea cohort).

Background: Micronuclei (MN) are biomarkers of early genetic effects that have been used to investigate the association between environmental exposures and cancer. However, few studies have examined the association between environmental exposures during pregnancy and MN in mothers and newborns.

Objectives: We examined MN frequency in maternal blood and in cord blood, in relation to maternal air pollution exposure, and the potential interaction with maternal vitamin C intake and maternal smoking.

Micronucleus frequency in Danish schoolchildren and their mothers from the DEMOCOPHES population.

Micronucleus (MN) frequency is a biomarker for early genetic effects which is often used in human biomonitoring studies. Increased frequency of micronuclei has been associated with high levels of traffic exposure. Further high MN frequency was found predictive for cancer development in several studies of adults.

The effect of dietary estimates calculated using food frequency questionnaires on micronuclei formation in European pregnant women: a NewGeneris study.

The use of biomarkers of early genetic effects, predictive for cancer, such as micronuclei (MN) in lymphocytes, may help to investigate the association between diet and cancer. We hypothesised that the presence of mutagens in the diet may increase MN formation. A 'pooled' standardised analysis was performed by applying the same experimental protocol for the cytokinesis block micronucleus assay in 625 young healthy women after delivery from five European study populations (Greece, Denmark, UK, Spain and Norway).

Lower nucleotide excision repair capacity in newborns compared to their mothers: a pilot study.

Recognition of the potential vulnerability of children and newborns and protection of their health is essential, especially regarding to genotoxic compounds. Benzo(a)pyrene B(a)P a commonly found carcinogen, and its metabolite BPDE, are known to cross the placenta. To investigate how well newborns are able to cope with BPDE-induced DNA damage, a recent developed nucleotide excision repair cell phenotype assay was applied in a pilot study of 25 newborn daughters and their mothers, using the Alkaline Comet Assay and taking demographic data into account.

Micronuclei in cord blood lymphocytes and associations with biomarkers of exposure to carcinogens and hormonally active factors, gene polymorphisms, and gene expression: the NewGeneris cohort.

Background: Leukemia incidence has increased in recent decades among European children, suggesting that early-life environmental exposures play an important role in disease development.

Objectives: We investigated the hypothesis that childhood susceptibility may increase as a result of in utero exposure to carcinogens and hormonally acting factors. Using cord blood samples from the NewGeneris cohort, we examined associations between a range of biomarkers of carcinogen exposure and hormonally acting factors with micronuclei (MN) frequency as a proxy measure of cancer risk.

Exposure to brominated trihalomethanes in water during pregnancy and micronuclei frequency in maternal and cord blood lymphocytes.

Background: Water disinfection by-products have been associated with an increased cancer risk. Micronuclei (MN) frequency in lymphocytes is a marker of genomic damage and can predict adult cancer risk.

Objective: We evaluated maternal exposure to drinking water brominated trihalomethanes (BTHM) in relation to MN frequency in maternal and cord blood lymphocytes.

Validation of the nucleotide excision repair comet assay on cryopreserved PBMCs to measure inter-individual variation in DNA repair capacity.

Inter-individual susceptibility to mutagens/carcinogens can be assessed by either genotyping DNA repair genes in different pathways or phenotyping DNA repair capacity (DRC) at the molecular or cellular level. Due to the large number of known DNA repair genes, and the interactions between repair pathways, phenotyping is becoming the preferred approach to measure DRC, and reliable assays are therefore increasingly needed. The use of a cellular phenotype comet assay for the nucleotide excision repair (NER) pathway using benzo[a]pyrene diol epoxide (BPDE) has been described in previous papers, but no thorough evaluation of its applicability in large genotype-phenotype studies has been presented.

Global gene expression analysis in cord blood reveals gender-specific differences in response to carcinogenic exposure in utero.

Background: It has been suggested that fetal carcinogenic exposure might lead to predisposition to develop cancer during childhood or in later life possibly through modulation of the fetal transcriptome. Because gender effects in the incidence of childhood cancers have been described, we hypothesized differences at the transcriptomic level in cord blood between male and female newborns as a consequence of fetal carcinogenic exposure. The objective was to investigate whether transcriptomic responses to dietary genotoxic and nongenotoxic carcinogens show gender-specific mechanisms-of-action relevant for chemical carcinogenesis.

Preterm newborns show slower repair of oxidative damage and paternal smoking associated DNA damage.

Newborns have to cope with hypoxia during delivery and a sudden increase in oxygen at birth. Oxygen will partly be released as reactive oxygen species having the potential to cause damage to DNA and proteins. In utero, increase of most (non)-enzymatic antioxidants occurs during last weeks of gestation, making preterm neonates probably more sensitive to oxidative stress.

Maternal and gestational factors and micronucleus frequencies in umbilical blood: the NewGeneris Rhea cohort in Crete.

Background: The use of cancer-related biomarkers in newborns has been very limited.

Objective: We investigated the formation of micronuclei (MN) in full-term and preterm newborns and their mothers from the Rhea cohort (Crete), applying for the first time in cord blood a validated semiautomated analysis system, in both mono- and binucleated T lymphocytes.

Methods: We assessed MN frequencies in peripheral blood samples from the mothers and in umbilical cord blood samples.

The in vitro MN assay in 2011: origin and fate, biological significance, protocols, high throughput methodologies and toxicological relevance.

Micronuclei (MN) are small, extranuclear bodies that arise in dividing cells from acentric chromosome/chromatid fragments or whole chromosomes/chromatids lagging behind in anaphase and are not included in the daughter nuclei at telophase. The mechanisms of MN formation are well understood; their possible postmitotic fate is less evident. The MN assay allows detection of both aneugens and clastogens, shows simplicity of scoring, is widely applicable in different cell types, is internationally validated, has potential for automation and is predictive for cancer.

Automated image analysis of micronuclei by IMSTAR for biomonitoring.

For many years, the analysis of micronuclei (MN) has been successfully applied to human biomonitoring of in vivo genotoxin exposure and provides a sensitive and relatively easy methodology to assess genomic instability. However, there is a need for automation of MN analysis for rapid, more reliable and non-subjective MN detection. In this review, we evaluate the application of automated image analysis of the in vitro cytokinesis-block MN assay on human lymphocytes for human biomonitoring, starting with the requirements that should be fulfilled by a valid and efficient image analysis system.

Evaluation of the genotoxicity of 10 selected dietary/environmental compounds with the in vitro micronucleus cytokinesis-block assay in an interlaboratory comparison.

Complex exposure to xenobiotics is one of the reasons for the reported increase of respiratory diseases, cancer and immunological disturbances. Among such xenobiotics there are food mutagens whose effects on human health in the low level and/or chronic exposure still remains unknown. In the present manuscript, the compounds ethanol (EtOH), 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4'-tetrachlorobiphenyl (PCB 153), benzo[a]pyrene (BaP), 2-amino-3-methylimidazol[4,5-f]quinoline (IQ), 2-amino-1-methyl-6-phenylimidazol[4,5-b]pyridine (PhIP), N-Nitrosodimethylamine (NDMA) and acrylamide (AA) were evaluated in an interlaboratory comparison in the in vitro cytokinesis-block micronucleus assay (CBMN) with objective of assessing the induction of micronuclei, buds and nucleoplasmic bridges in dose responses.

Phenotyping for DNA repair capacity.

The ability to repair DNA damage is strongly associated with the risk of cancer and other human diseases as it is essential for maintenance of genome stability. Moreover, DNA repair capacity is an important factor contributing to the inter-individual variability in mutagen exposure, cancer development and treatment through an individualized adjusted therapy. In addition to genotypes, functional phenotypic assays which integrate the different pathways provide useful tools to explore the role of DNA repair in cancer susceptibility.

An aphidicolin-block nucleotide excision repair assay measuring DNA incision and repair capacity.

The objective of the present study was to develop a cellular phenotype assay for nucleotide excision repair (NER), using benzo[a]pyrene diol epoxide (BPDE) as model mutagen. Since in vitro exposure to BPDE may lead to DNA strand breaks resulting from both direct interaction with DNA and incisions introduced by the repair enzymes, we aimed to discriminate between both types of breaks using the comet assay and quantified the DNA strand breaks after in vitro challenge of peripheral blood mononucleated cells (PBMCs) with BPDE in the presence or absence of the DNA polymerase inhibitor aphidicolin (APC). The assay was performed with a low (0.

Automated image analysis of cytokinesis-blocked micronuclei: an adapted protocol and a validated scoring procedure for biomonitoring.

Micronuclei (MN) frequencies in peripheral blood lymphocytes have been used worldwide as a biomarker of chromosomal damage for genotoxicity testing and biomonitoring studies. Automation of MN analysis would provide faster and more reliable results with minimizing subjective MN identification. We developed an automated facility for the scoring of the in vitro MN cytokinesis-block assay for biomonitoring on Giemsa-stained slides, fulfilling the following criteria: applicable to the cytokinesis-block micronucleus methodology, discriminating between mono-, bi- and polynucleated cells, MN scoring according to HUMN scoring criteria, false-negative MN rate <10% and false-positive (FP) MN rate <1%.