Micronucleus-centromere assay and DNA repair gene polymorphism in lymphocytes of industrial radiographers

Cho, Yoon Hee; Kim, Yang Jee; An, You Sun; Woo, Hae Dong; Choi, Sujin; Kang, Chang Mo; Chung, Hai Won

doi:10.1016/j.mrgentox.2009.08.007

Cited by 21 publications

(12 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Fig 1 illustrates the causal path from age to MNC+ (top); and the mediational model of age, LINE-1 hypomethylation (the mediator), and MNC+ (bottom). As shown in the top panel of the figure, age significantly predicted MNC+, b = 0.13, t (30) = 4.51, p < 0.001, which is consistent with previous studies [ 29 ]. As shown in the bottom panel, age significantly predicted LINE-1 hypomethylation, b = -4.39, t (30) = -3.14, p < 0.01.…”

Section: Resultssupporting

confidence: 91%

“…Vral et al[ 28 ] reported that a high percentage of spontaneous MN are also MNC+. Our previous study also showed that MNC+ frequency significantly increases with age, suggesting that the presence of MNC+ may serve as a valuable age-dependent biomarker for genomic instability [ 29 ]. However, the mechanisms underlying age-induced genomic instability and disease risk are not yet clear.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Association of LINE-1 Hypomethylation with Age and Centromere Positive Micronuclei in Human Lymphocytes

et al. 2015

Self Cite

View full text Add to dashboard Cite

Global hypomethylation in white blood cell (WBC) DNA has recently been proposed as a potential biomarker for determining cancer risk through genomic instability. However, the amplitude of the changes associated with age and the impacts of environmental factors on DNA methylation are unclear. In this study, we investigated the association of genomic hypomethylation with age, cigarette use, drinking status and the presence of centromere positive micronuclei (MNC+)—a biomarker for age-dependent genomic instability. Genomic hypomethylation of the repetitive element LINE-1 was measured in WBC DNA from 32 healthy male volunteers using the pyrosequencing assay. We also measured MNC+ with the micronucleus-centromere assay using a pan-centromeric probe. Possibly due to the small sample size and resulting low statistical power, smoking and drinking status had no significant effect on LINE-1 hypomethylation or the occurrence of MNC+. Consequently, we did not include them in further analyses. In contrast, LINE-1 hypomethylation and age significantly predicted MNC+; therefore, we examined whether LINE-1 hypomethylation plays a role in MNC+ formation by age, since genomic hypomethylation is associated with genomic instability. However, LINE-1 hypomethylation did not significantly mediate the effect of age on MNC+. Our data indicate that the repetitive element LINE-1 is demethylated with age and increasing MNC+ frequency, but additional studies are needed to fully understand the relation between genomic DNA hypomethylation, age and genomic instability.

show abstract

Section: Resultssupporting

confidence: 91%

Section: Introductionmentioning

confidence: 99%

The Association of LINE-1 Hypomethylation with Age and Centromere Positive Micronuclei in Human Lymphocytes

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…Therefore, we further investigated the effects of low‐level occupational radiation exposure among radiographers. The frequency of MN in radiographers was significantly increased by all radiation exposure doses (recent 1‐year, recent 3‐year, and total cumulative during working duration); these results agree with other previous studies suggesting that MN can be used as a predictive marker for occupational radiation exposure in radiographers [Sari‐Minodier et al, ; Cho et al, ]. Further, aneuploidy frequency in radiographers was significantly increased by cumulative exposure, but not by recent 1‐ or 3‐year radiation exposure.…”

Section: Discussionsupporting

confidence: 90%

“…The study population comprised 40 male industrial radiographers and 28 healthy volunteers in Seoul, Korea. All radiographers were occupationally exposed to low linear energy transfer (LET) radiation, including x‐ or γ‐rays at low‐dose to evaluate the quality of welded joints, pipes, tanks, or constructions as previously described [Cho et al, ]. The official personal dosimetry records based on monthly film dosimeters were collected for each radiographer for the whole working period and used to estimate occupational radiation dosages.…”

Section: Methodsmentioning

confidence: 99%

LINE‐1 hypomethylation is associated with radiation‐induced genomic instability in industrial radiographers

Cho

Jang

Woo

et al. 2018

Environ and Mol Mutagen

Self Cite

View full text Add to dashboard Cite

Global DNA hypomethylation is proposed as a potential biomarker for cancer risk associated with genomic instability, which is an important factor in radiation‐induced cancer. However, the associations among radiation exposure, changes in DNA methylation, and carcinogenesis are unclear. The aims of this study were (1) to examine whether low‐level occupational radiation exposure induces genomic DNA hypomethylation; and (2) to determine the relationships between radiation exposure, genomic DNA hypomethylation and radiation‐induced genomic instability (RIGI) in industrial radiographers. Genomic DNA methylation levels were measured in blood DNA from 40 radiographers and 28 controls using the LINE‐1 pyrosequencing assay and the luminometric methylation assay. Further, the micronucleus‐centromere assay was performed to measure aneuploidy of chromosomes 1 and 4 as a marker of delayed RIGI. Genomic DNA methylation levels were significantly lower in radiographers than those in controls. LINE‐1 hypomethylation was not significantly correlated with recent 1‐year, recent 3‐year, or total cumulative radiation doses in radiographers; however, LINE‐1 hypomethylation significantly correlated with the cumulative radiation dose without recent 3‐year exposure data (D3dose, r = −0.39, P < 0.05). In addition, LINE‐1 hypomethylation was a significant contributor to aneuploidy frequency by D3dose (F (2, 34) = 13.85, P < 0.001), in which a total of 45% of the variance in aneuploidy frequency was explained. Our results provide suggestive evidence regarding the delayed effects of low‐dose occupational radiation exposure in radiographers and its association with LINE‐1 hypomethylation; however, additional studies using more subjects are needed to fully understand the relationship between genomic DNA hypomethylation and RIGI. Environ. Mol. Mutagen. 60: 174–184, 2019. © 2018 Wiley Periodicals, Inc.

show abstract

“…Previous studies had shown that XRCC3 polymorphisms contribute to increased frequencies of MNs [31]. In the same context, Cho et al [32] showed that the variant allele of XRCC3 influenced the C-MN frequency in radiographers. It may suggest an altered protein product resulting in suboptimal repair of radiation-induced damage leading to an increase in MNs.…”

Section: Discussionmentioning

confidence: 94%

A cytogenetic approach to the effects of low levels of ionizing radiation (IR) on the exposed Tunisian hospital workers

Bouraoui¹,

Mougou²,

Drira³

et al. 2013

International Journal of Occupational Medicine and Environmental Health

View full text Add to dashboard Cite

Objectives: The aim of this study is to assess chromosomal damage in Tunisian hospital workers occupationally exposed to low levels of ionizing radiation (IR). Materials and Methods: The cytokinesis-block micronucleus (CBMN) assay in the peripheral lymphocytes of 67 exposed workers compared to 43 controls matched for gender, age and smoking habits was used. The clastogenic/aneugenic effect of IR was evaluated using the CBMN assay in combination with fluorescence in situ hybridization with human pan-centromeric DNA in all the exposed subjects and controls. Results: The study showed a significant increase of the micronucleus (MN) frequency in the lymphocytes of the exposed workers compared to the control group (13.63±4.9‰ vs. 6.52±4.21‰, p < 0.05). The centromere analysis performed in our study showed that MNs in hospital staff were predominantly centromere negative (72%) and the mean negative labeled micronucleus (C-MN) frequency was significantly higher in the exposed subjects than in the controls (9.04±4.57‰ vs. 1.17±0.77‰). The multivariate regression analysis, taking into account all confounding factors, showed that only the time of exposure to IR had a significant effect on the level of MNs and C-MN. Conclusion: The present study shows that chromosomal damage leading to the formation of micronucleated lymphocytes is more frequent in the hospital workers exposed to IR than in the controls, despite the low levels of exposure. The results of the study confirm the well-known clastogenic properties of ionizing radiation. In regards to health monitoring, detection of early genotoxic effects may allow for the adoption of preventive biological control measures, such as hygienic improvements in the workplace or reduction of hours of occupational exposure.

show abstract

Micronucleus-centromere assay and DNA repair gene polymorphism in lymphocytes of industrial radiographers

Cited by 21 publications

References 45 publications

The Association of LINE-1 Hypomethylation with Age and Centromere Positive Micronuclei in Human Lymphocytes

The Association of LINE-1 Hypomethylation with Age and Centromere Positive Micronuclei in Human Lymphocytes

LINE‐1 hypomethylation is associated with radiation‐induced genomic instability in industrial radiographers

A cytogenetic approach to the effects of low levels of ionizing radiation (IR) on the exposed Tunisian hospital workers

Contact Info

Product

Resources

About