scholarly journals Nested PCR for mtDNA-4977-bp deletion and comet assay for DNA damage - a combined method for radiosensitivity evaluation of tumor cells

2014 ◽  
Vol 7 (4) ◽  
pp. 1083-1087 ◽  
Author(s):  
JIANGUO LI ◽  
YAN WANG ◽  
LIQING DU ◽  
CHANG XU ◽  
JIA CAO ◽  
...  
2017 ◽  
Vol 39 (4) ◽  
pp. 299-303 ◽  
Author(s):  
L G Buchynska ◽  
O V Brieieva ◽  
N P Iurchenko ◽  
V V Protsenko ◽  
S V Nespryadko

To date, genome instability is considered to be a common feature not only of tumor cells, but also of non-malignant cells of cancer patients, including peripheral blood lymphocytes (PBLs). The issue of the association between genome instability in tumor cells and PBLs, as well as of its relationship with tumor progression remains poorly understood. Aim: To evaluate the level DNA damage in tumor cells and PBLs of endometrial cancer (EC) patients with regard to clinical and morphological characteristics of the patients. Materials and Methods: DNA damage was assessed in 106 PBLs samples and 42 samples of tumor cell suspension from EC patients by comet assay. PBLs from 30 healthy women were used as control. The level of DNA damage was expressed as the percentage of DNA in the comet tails (% tail DNA). Results: It was revealed that the amount of DNA damage in PBLs of EC patients was 2.2 times higher in comparison with that of healthy donors (8.3 ± 0.7 and 3.7 ± 0.4% tail DNA, respectively) (p < 0.05). In this study, no association between the levels of DNA damage in endometrial tumor cells and PBLs was observed (r = 0.11; p > 0.05). The amounts of DNA damage both in tumor cells and PBLs were not related to the degree of tumor differentiation as well as the depth of myometrial invasion, but depended on the body mass index (BMI) of EC patients: high level of lesions was observed in patients with elevated BMI values. Furthermore, the level of DNA damage in tumor cells was associated to familial aggregation of cancer and was significantly higher in endometrial cells from patients with family history of cancer vs that from EC patients with sporadic tumors (32.3 ± 2.9 and 22.8 ± 1.8% tail DNA, respectively) (p < 0.05). It was also found that for women who had high level of DNA damage in PBLs, the risk of EC was greater (odds ratio value of 3.5) compared to those with low level of such lesions. Conclusion: Genome instability that appears as an increased level of DNA damage in tumor cells and PBLs of EC patients is associated with BMI and family history of cancer and can reflect a predisposition to cancer.


1999 ◽  
Vol 96 (1) ◽  
pp. 143-146 ◽  
Author(s):  
J.-P. Pouget ◽  
J.-L. Ravanat ◽  
T. Douki ◽  
M.-J. Richard ◽  
J. Cadet

2020 ◽  
Vol 16 (7) ◽  
pp. 1072-1082
Author(s):  
Tuba C. Dördü ◽  
Rüştü Hatipoğlu ◽  
Mehmet Topaktaş ◽  
Erman S. İstifli

Background: Ellagic Acid (EA) is a polyphenolic compound that is classified in the natural antioxidants group. Polyphenolic compounds that exert antioxidant activity possess particular importance for scientists, food producers and consumers due to their positive effects on human health. However, despite considerable evidence that EA shows antigenotoxic activity by binding to DNA, there is no systematic genotoxicity study of this substance, which can covalently bind to DNA. This study aims to reveal the possible genotoxic activity of EA using widely accepted assays for the assessment of DNA clastogenic activity: sister chromatid exchange, chromosome aberration, micronucleus and comet assays as well as to predict the interactions among EA and DNA through molecular docking. Methods: Different assays were carried out to identify the clastogenic activity of EA on human lymphocyte DNA using Sister Chromatid Exchange (SCE), Chromosome Aberration (CA), Micronucleus (MN) and single-cell gel electrophoresis (SCGE/comet) assays. For this aim, human peripheral blood lymphocytes were treated with EA (60, 80 and 100 μg/ml) for 24 and 48 hrs in the SCE, CA and MN assays and for 1 hr in the comet assay. Furthermore, molecular docking experiments were also performed to calculate the binding energy of EA on human B-DNA structure (B-DNA dodecamer) as well as to predict noncovalent interactions among these macromolecules. Results: At the concentrations and treatment times (24- or 48-hr) tested, EA did not induce either SCE or Chromosome Aberrations (CAs) as compared to the negative and solvent controls. Although EA slightly increased the percentage of Micronucleated Binuclear (%MNBN) cells as well as the percentage of Micronucleus (%MN) in 24 or 48-hr treatment periods at all concentrations, this increase was not statistically significant as compared to both controls. The effect of EA on DNA replication (nuclear division) was determined by the Proliferation Index (PI), the Nuclear Division Index (NDI) and the Mitotic Index (MI). No statistically significant differences were observed in the PI or NDI in 24- or 48-hr treatment periods in human lymphocyte cultures treated with EA at various concentrations. EA generally had no significant effect on the MI, as observed with the PI and NDI. Discussion: Although the concentrations of 60 and 80 μg/mL at a 24-hr treatment period and the concentrations of 60 μg/mL and 100 μg/mL at 48-hr treatment period generally decreased the MI, those decreases were not statistically significant when compared to negative and solvent controls. Moreover, none of the concentrations of EA tested in this study were able to increase DNA damage determined by the tail DNA length, %DNA in tail and tail moment parameters in the comet assay. Although the amount of DNA damage in the comet assay decreased with increasing concentrations of EA, this decrease was not statistically significant as compared to both controls. However, molecular docking experiments interestingly showed that the binding free energy of EA with B-DNA was -7.84 kcal/mol-1, indicating a strong interaction between the two molecules. Conclusion : Although the findings of our study show that EA does not have genotoxic potential in human chromosomes, molecular docking experiments revealed strong hydrogen bonding between EA and B-DNA molecules. Therefore, it has been proposed that the prevailing information suggesting that the molecules that bind to DNA cause genotoxic effects should be reconsidered from a wider perspective.


2020 ◽  
Vol 20 (3) ◽  
pp. 453-463
Author(s):  
Svetlana Yagubova ◽  
Aliy Zhanataev ◽  
Rita Ostrovskaya ◽  
Еlena Anisina ◽  
Тatiana Gudasheva ◽  
...  

Background: NGF deficiency is one of the reasons for reduced β-cells survival in diabetes. Our previous experiments revealed the ability of low-weight NGF mimetic, GK-2, to reduce hyperglycaemia in a model of advanced diabetes. The increase in DNA damage in advanced diabetes was repeatedly reported, while there were no data about DNA damage in the initial diabetes. Aim: The study aimed to establish whether DNA damage occurs in initial diabetes and whether GK-2 is able to overcome the damage. Methods: The early-stage diabetes was modelled in Balb/c mice by streptozotocin (STZ) (130 mg/kg, i.p.). GK-2 was administered at a dose of 0.5 mg/kg, i.p., subchronically. The evaluation of DNA damage was performed using the alkaline comet assay; the percentage of DNA in the tail (%TDNA) and the percentage of the atypical DNA comets (“ghost cells”) were determined. Results: STZ at this subthreshold dose produced a slight increase in glycemia and MDA. Meanwhile, pronounced DNA damage was observed, concerning mostly the percentage of “ghost cells” in the pancreas, the liver and kidneys. GK-2 attenuated the degree of hyperglycaemia and reduced the % of “ghost cells” and %TDNA in all the organs examined; this effect continued after discontinuation of the therapy. Conclusion: Early-stage diabetes is accompanied by DNA damage, manifested by the increase of “ghost cells” percentage. The severity of these changes significantly exceeds the degree of hyperglycaemia and MDA accumulation. GK-2 exerts an antihyperglycaemic effect and attenuates the degree of DNA damage. Our results indicate that the comet assay is a highly informative method for search of antidiabetic medicines.


2009 ◽  
Vol 157 (5) ◽  
pp. 1565-1572 ◽  
Author(s):  
Zlatko Mihaljević ◽  
Ivančica Ternjej ◽  
Igor Stanković ◽  
Mladen Kerovec ◽  
Nevenka Kopjar

2004 ◽  
Vol 23 (8) ◽  
pp. 413-419 ◽  
Author(s):  
Cetin Kaymak ◽  
Ela Kadioglu ◽  
Hulya Basar ◽  
Semra Sardas

In this study, genotoxic effects of repeated sevoflurane anaesthesia were investigated in rabbits with or without antioxidant supplementation. Twenty-one New Zealand male rabbits were included in the study and randomized into three groups as: placebo treated (Group I), vitamin E supplemented (Group II) and selenium supplemented (Group III). Vitamin E and selenium were given intraperitoneally for 15 days before anaesthesia treatment. Anaesthesia was administered using 3% sevoflurane in 4 L/min oxygen for a 3-hour period and continued for 3 days. Blood samples were collected before anaesthesia (Sample 1), after the first, second and third days of sevoflurane administration (Sample 2, Sample 3 and Sample 4 respectively) and the last samples were taken 5 days after the last sevoflurane administration (Sample 5). Genotoxic damage was examined using the comet assay. The degree of damage is assessed by grading the cells into three categories of no migration (NM), low migration (LM) and high migration (HM) depending on the fraction of DNA pulled out into the tail under the influence of the electric field. The number of comets in each sample was calculated (1 × number of comets in category NM + 2 × number of comets in category LM + 3 ×number of comets in category HM) and expressed as the total comet score (TCS), which summarizes the damage frequencies. In Group I, a significant increase in the mean TCSs was observed for Samples 3 and 4 as compared with Sample 1. However, there were no significant differences between Samples 1, 2 and 5. The mean TCS of Sample 4 was significantly higher than Sample 1, 2 and 3 in Group II. Group III demonstrated no significant mean TCSs for any experimental conditions. Statistical differences were also observed between the groups with significant P values. This experimental study points out the presence of DNA damage with repeated sevoflurane anaesthesia and the genoprotective role of antioxidant supplementation on DNA damage in mononuclear leukocytes of rabbits by highly sensitive comet assay.


2015 ◽  
Vol 72 (1) ◽  
pp. 141-149 ◽  
Author(s):  
Annette Dalrymple ◽  
Patricia Ordoñez ◽  
David Thorne ◽  
Debbie Dillon ◽  
Clive Meredith

Author(s):  
Banu Aykanat ◽  
Gonca Cakmak Demircigil ◽  
Kibriya Fidan ◽  
Necla Buyan ◽  
Kaan Gulleroglu ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document