A pooled analysis of host factors that affect nucleotide excision repair in humans

Nucleotide excision repair (NER) is crucial for repairing bulky lesions and crosslinks in DNA caused by exogenous and endogenous genotoxins. The number of studies that have considered DNA repair as a biomarker is limited, and therefore one of the primary objectives of the European COST Action hCOMET (CA15132) was to assemble and analyse a pooled database of studies with data on NER activity. The database comprised 738 individuals, gathered from 5 laboratories that ran population studies using the comet-based in vitro DNA repair assay. NER activity data in peripheral blood mononuclear cells were normalized and correlated with various host-related factors, including sex, age, body mass index (BMI), and smoking habits. This multifaceted analysis uncovered significantly higher NER activity in female participants compared to males (1.08 ± 0.74 vs. 0.92 ± 0.71; P = .002). Higher NER activity was seen in older subjects (>30 years), and the effect of age was most pronounced in the oldest females, particularly those over 70 years (P = .001). Females with a normal BMI (<25 kg/m2) exhibited the highest levels of NER, whereas the lowest NER was observed in overweight males (BMI ≥ 25 kg/m2). No independent effect of smoking was found. After stratification by sex and BMI, higher NER was observed in smoking males (P = .017). The biological implication of higher or lower repair capacity remains unclear; the inclusion of DNA repair as a biomarker in molecular epidemiological trials should elucidate the link between health and disease status.

An Unusual Case of a Monorchid Horse with an Abdominally Retained Testicle

INTRODUCTION

Monorchidism is a rarely described condition in the horse and is not to be confused with cryptorchidism. The diagnosis is challenging and confirmed by surgery and histology in combination with hormonal assays. This report describes, to the best of the author's knowledge, the first case of monorchidism and abdominal cryptorchidism of the developed testicle in a horse.

METHODS

An Irish Cob underwent laparoscopic castration for removal of bilateral cryptorchid testicles. At surgery, the horse was diagnosed as a monorchid with the testicle retained intra-abdominally. Histopathological, hormonal, molecular and cytogenetic analysis was performed. This included measuring testosterone and anti-Mullerian hormone (AMH) in serum blood, isolating genomic DNA from EDTA- and heparin-treated blood, PCR amplification of the SRY gene, metaphase chromosome preparation, and DAPI banding before metaphase analysis with fluorescence in situ hybridisation (FISH) analysis.

RESULTS

The horse was positive for the SRY gene and had a mosaic 63,X/64,XY karyotype with the aneuploid cells being present in only 2% of metaphases. FISH showed that the missing sex chromosome of the aneuploid cell line was the Y chromosome embedded in micronuclei. An abnormal high rate of micronuclei (6.6%) was observed indicating genotoxic events and/or genome instability. Hormonal assay results confirmed that AMH was not significantly increased, suggesting that no further testicular tissue was present. Histopathology was consistent with testicular tissue displaying a Sertoli cell-only pattern with bipolar ductal structures.

CONCLUSION

The exact causes of monorchidism and cryptorchidism are unclear, but the elevated rate of micronuclei is clear evidence for genome instability which might have been involved in the failure of normal testicular development and descent. Future cases could further clarify the disease mechanism based on this report.

Genetic Damage and Multi-Elemental Exposure in Populations in Proximity to Artisanal and Small-Scale Gold (ASGM) Mining Areas in North Colombia

This study evaluates DNA damage and multi-element exposure in populations from La Mojana, a region of North Colombia heavily impacted by artisanal and small-scale gold mining (ASGM). DNA damage markers from the cytokinesis-block micronucleus cytome (CBMN-Cyt) assay, including micronucleated binucleated cells (MNBN), nuclear buds (NBUDs) and nucleoplasmic bridges (NPB), were assessed in 71 exposed individuals and 37 unexposed participants. Exposed individuals had significantly higher MNBN frequencies (PR = 1.26, 95% CI: 1.02-1.57, p = 0.039). Principal Component Analysis (PCA) identified the "Soil-Derived Mining-Associated Elements" (PC1), including V, Fe, Al, Co, Ba, Se and Mn, as being strongly associated with high MNBN frequencies in the exposed population (PR = 10.45, 95% CI: 9.75-12.18, p < 0.001). GAMLSS modeling revealed non-linear effects of PC1, with greater increases in MNBN at higher concentrations, especially in exposed individuals. These results highlight the dual role of essential and toxic elements, with low concentrations being potentially protective but higher concentrations increasing genotoxicity. Women consistently exhibited higher MNBN frequencies than men, suggesting sex-specific susceptibilities. This study highlights the compounded risks of chronic metal exposure in mining-impacted regions and underscores the urgent need for targeted interventions to mitigate genotoxic risks in vulnerable populations.

The intervention of NLRP3 inflammasome inhibitor: oridonin against azoxymethane and dextran sulfate sodium-induced colitis-associated colorectal cancer in male BALB/c mice

Colorectal cancer (CRC) ranks third globally in cancer diagnoses. The dysregulation of the NLRP3 inflammasome is prominently linked to several types of cancers. Oridonin, a principal component of Rabdosia rubescens, exhibits inhibitory activity against NLRP3 and is well-recognized for its diverse pharmacological benefits. However, its role in an animal model of colitis-associated colorectal cancer (CACC) remains unexplored. In the present study, the effectiveness of oridonin was investigated against CACC, developed using azoxymethane (AOM), a tumour initiator, and dextran sulphate sodium (DSS), a tumour promoter, in male BALB/c mice. The two-stage murine model of inflammation-associated cancer was established by administering AOM (10 mg/kg b.w.; i.p., once) followed by DSS (2% w/v) in drinking water (3 cycles, 7 days/cycle). Over a span of 10 weeks, the dose-dependent (2.5, 5, and 10 mg/kg, b.w.; i.p.) effects of oridonin were investigated in BALB/c mice. Oridonin significantly alleviated CACC severity, as evidenced by reduced DAI scores and restored body weight. Moreover, it attenuated surrogate markers of inflammation, including myeloperoxidase, nitrite, plasma LPS, TNF-α, IL-1β, and DNA damage. Histopathological examination revealed diminished tumorigenesis and apoptotic cells, corroborated by reduced Ki-67 and TNF-α, along with increased p53 expression in the colon. Following oridonin treatment, IHC/immunofluorescence analyses demonstrated a significantly reduced expression of the components of NLRP3 inflammasome including NLRP3, ASC-1, and caspase-1. Notably, the high dose of oridonin (10 mg/kg) consistently exhibited significant protective effects against CACC by modulating various molecular targets. Present findings confirmed the potential of oridonin in the protection of colitis-associated colorectal cancer, providing valuable insights into its mechanism of action and clinical significance.

Does waterpipe smoke induce genotoxicity (DNA damage) in mammalian cells in vivo? A systematic review

The waterpipe works by placing tobacco in a bowl with holes at the bottom, which is connected to a tube leading to a water-filled container. Upon heating the tobacco product with hot charcoal placed atop it, the emanating smoke is inhaled by the user via a hose linked to the water receptacle. The aim of this literature review is to evaluate whether the use of waterpipes can indeed induce genotoxicity in mammalian cells in vivo. Additionally, the study aims to assess the quality of the included research articles on this topic to ensure the reliability of the findings. We performed comprehensive searches in PubMed, SCOPUS, and Web of Science to identify relevant articles published until July 2024. The findings confirmed that waterpipe smoke induces genetic damage. This assertion is supported by the fact that 11 studies (out of 15) received a Strong or Moderate assessment categorization, suggesting that the majority of studies adhered to most technical standards, thereby enhancing the reliability of the research findings. Regarding the types of DNA damage reported, DNA strand breaks, chromosome damage and oxidative DNA damage were found in this review. Taken together, this study holds significant importance in assessing the efficacy of genotoxicity assays in detecting DNA damage due to waterpipe smoke and the comet and micronucleus assays are suitable biomarkers for biomonitoring people who use waterpipe.

Do firefighters constitute a high-risk population for genotoxicity (DNA damage)? A systematic review

Firefighters regularly undertake high-risk operations in diverse environments, exposing them to extreme temperatures and hazardous pollutants resulting from combustion. For this reason, this systematic review aims to evaluate the potential genotoxicity associated with occupational exposure specific to firefighters. Methodologically, the review included 12 studies assessing genetic damage in firefighters. A thorough quality assessment was performed to account for potential confounding factors, and almost all studies were deemed as either strong or moderate (except for one), ensuring the reliability of the key findings. Likewise, more than half of the articles reviewed (7 out of 12) reported elevated levels of genotoxicity in firefighters, as evidenced by various assays employed in the studies. Taken together, the findings highlight the critical need for implementing biomonitoring strategies for early detection of genotoxicity among firefighters, emphasizing the necessity for further research in this occupational context.

Investigating Chromosomal Radiosensitivity in Inborn Errors of Immunity: Insights from DNA Repair Disorders and Beyond

Human inborn errors of immunity (IEI) represent a diverse group of genetic disorders affecting the innate and/or adaptive immune system. Some IEI entities comprise defects in DNA repair factors, resulting in (severe) combined immunodeficiencies, bone marrow failure, predisposition to malignancies, and potentially resulting in radiosensitivity (RS). While other IEI subcategories such as common variable immunodeficiency (CVID) and immune dysregulation disorders also associate with lymphoproliferative and malignant complications, the occurrence of RS phenotypes in the broader IEI population is not well characterized. Nonetheless, identifying RS in IEI patients through functional testing is crucial to reconsider radiation-related therapeutic protocols and to improve overall patient management. This study aimed to investigate chromosomal RS in a diverse cohort of 107 IEI patients using the G0 cytokinesis-block micronucleus (MN) assay. Our findings indicate significant variability in RS across specific genetic and phenotypical subgroups. Severe RS was detected in all ataxia-telangiectasia (AT) patients, a FANCI deficient and ERCC6L2 deficient patient, but not in any other IEI patient included in this cohort. Age emerged as an influencing factor for both spontaneous and radiation-induced MN yields, while the manifestation of additional clinical features, including infection susceptibility, immune dysregulation, or malignancies did not associate with increased MN levels. Our extensive analysis of RS in the IEI population underscores the clinical importance of RS assessment in AT patients and supports RS testing in all IEI patients suspected of having a DNA repair disorder associated with RS.

A pilot study of the value of micronucleus count in urinary cytology samples in the follow-up of patients with urothelial carcinoma: Implications for diagnosis and prognosis

BACKGROUND

Nuclear protrusions such as micronuclei (MNs) and nuclear budding (NB) are morphological findings of chromosomal instability and indicators of genotoxic damage. They are increased in malignancies, and their high frequency may be used in the diagnosis of cancers and the follow-up of patients. Urothelial carcinomas are common tumors that cause morbidity and mortality, and cytology is a commonly used method for the monitoring and screening of urothelial carcinoma. Although the cytological evaluation of urinary samples is mainly based on nuclear features, there is limited research focusing on MN frequency in urinary cytology. This study aimed to investigate MN and NB counts in various diagnostic categories of urinary samples.

METHODS

This study included 117 urinary cytology samples categorized according to The Paris System for Reporting of Urinary Cytology. Two observers, blinded to the diagnosis, counted the frequency of MNs and NB per 1000 cells on May-Grünwald-Giemsa- and Papanicolaou-stained slides.

RESULTS

MN and NB counts significantly differed among the groups (p < .001 for each) with a large effect (Ɛ2 = 0.509). MN and NB counts were significantly higher in cases with high-grade urothelial carcinoma (HGUC) than in control cases and in cases that were negative for HGUC or with atypical urothelial cells (p < .001 for each). Any MN count greater than 2.5 per 1000 cells indicated HGUC with a 55% sensitivity and 92.4% specificity.

CONCLUSIONS

Because increased MN and NB frequencies are closely associated with an increased risk of malignancy, these could be integrated into The Paris System for Reporting of Urinary Cytology.

The Impact of the Metabolic Syndrome Severity on the Appearance of Primary and Permanent DNA Damage

The prevalence of metabolic syndrome (MetS) worldwide is rapid and significant on a global scale. A 2022 meta-analysis of data from 28 million individuals revealed a global prevalence of 45.1%, with notably higher rates in the Eastern Mediterranean Region and the Americas, particularly in high-income countries. MetS is associated with impaired antioxidant defense mechanisms, resulting in the excessive generation of reactive oxygen and nitrogen species (RONS) and elevated levels of DNA damage. Unrepaired damage can lead to DNA base changes, chromosomal mutations, genomic loss and instability, and disrupted gene and protein expression. Such changes contribute to an increased risk of tumorigenesis, cancer progression, and mortality. The alkaline comet and micronucleus cytome assay are commonly used assays for DNA damage evaluation. The estimation of damage with those two techniques demonstrated the link between the increased risk of cancer and mortality. Incorporating these techniques in a set of biomarkers to assess the MetS severity holds promise; however, comprehensive literature reviews featuring large-scale studies integrating both assays remain scarce. This systematic review aims to integrate and critically evaluate the existing scientific literature regarding this topic.

Effects of Short-Term Treatment with α-Lipoic Acid on Neuropathic Pain and Biomarkers of DNA Damage in Patients with Diabetes Mellitus

BACKGROUND/OBJECTIVES

Diabetes mellitus (DM) is a complex and heterogenous disease classified as a group of metabolic disorders characterized by chronic hyperglycemia resulting from defects in insulin secretion, insulin action, or both. It leads to various complications, some of which are macrovascular or microvascular complications, like diabetic polyneuropathy (DPN), having a profound impact on patients' quality of life. Oxidative stress (OS) is one of the significant mechanisms in the development and progression of DPN. Thus, targeting OS pathways by antioxidants, such as α-lipoic acid (ALA), could represent a promising therapeutic strategy for alleviating neuropathic symptoms. The aim of our study was to evaluate whether short-term (from 4 to 9 days) intravenous administration of ALA could cause any measurable improvement in subjects with DM.

METHODS

Sixteen subjects with DM (six type 1 and ten type 2) and sixteen nondiabetic subjects matched by sex and age were recruited to this study. Only subjects with DM received treatment with ALA (600 mg daily). Pain intensity and biomarkers of DNA damage including plasma concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG), frequency of micronucleated lymphocytes (MN), and frequency of sister-chromatid exchanges (SCEs), were measured before and after the treatment with ALA.

RESULTS

Pain intensity and 8-OHdG levels were significantly lower in DM subjects after the ALA treatment than before the treatment. However, no changes in the frequency of SCEs and MN were observed.

CONCLUSIONS

Our results show some evidence that even a short-term intravenous treatment with ALA could be beneficial for diabetic subjects, reducing pain intensity and concentration of 8-OHdG in blood plasma.

Study of Radiosensitivity and Induction of Radiation Adaptive Response in Peripheral Blood Lymphocytes of Patients with Oncological Diseases Using the Micronuclear Test

Radiosensitivity to low and medium doses of X-ray radiation and the ability to induce a radiation adaptive response (RAR) of lymphocytes during in vitro irradiation of peripheral blood of patients with cancer were studied. The criterion for cytogenetic damage was the frequency of micronuclei (MN) in cytochalasin-blocked binucleate lymphocytes in culture. It was found that the spontaneous level of cytogenetic damage in the lymphocytes of patients was 2.6 times higher than in healthy volunteers, and there was also significant interindividual variability in values compared to the control cohort. There were no differences in mean values for radiosensitivity to low and medium doses of X-ray between the study groups. There was no correlation between the spontaneous level of MN in lymphocytes and the radiosensitivity of individuals in both groups. RAR was induced with the same frequency and to the same extent in lymphocytes from both patients and healthy individuals.

Is micronucleus assay in oral cells suitable biomarker for evaluating the risk of carcinogenesis in gas station attendants? A systematic review

This study aimed to evaluate all studies which used the micronucleus assay using oral cells in the attempt to understand whether such technique is efficient in evaluating genotoxicity in gas station attendants. Full manuscripts from 16 studies were carefully selected by the authors. Our results demonstrate that continuous exposure to derivatives of petroleum may lead to genotoxic effects since all studies demonstrated positive findings (16 out of 16) and 11 of them had a strong or moderate final rating. In summary, our results reveal that gas station attendants are occupationally exposed to genotoxic agents and that the micronucleus assay in oral mucosa is indeed an effective method to evaluate genotoxicity in this specific case. Such findings are very important for protecting these professionals who are continuously exposed to chemicals for long periods.

Residential exposure to air pollution and incidence of leukaemia in the industrial area of Viadana, Northern Italy

BACKGROUND

Exposure to air pollution has been proposed as one of the potential risk factors for leukaemia. Work-related formaldehyde exposure is suspected to cause leukaemia.

METHODS

We conducted a nested register-based case-control study on leukaemia incidence in the Viadana district, an industrial area for particleboard production in Northern Italy. We recruited 115 cases and 496 controls, frequency-matched by age, between 1999 and 2014. We assigned estimated exposures to particulate matter (PM10, PM2.5), nitrogen dioxide (NO2), and formaldehyde at residential addresses, averaged over the susceptibility window 3rd to 10th year prior to the index date. We considered potential confounding by sex, age, nationality, socio-economic status, occupational exposures to benzene and formaldehyde, and prior cancer diagnoses.

RESULTS

There was no association of exposures to PM10, PM2.5, and NO2 with leukaemia incidence. However, an indication of increased risk emerged for formaldehyde, despite wide statistical uncertainty (OR 1.46, 95%CI 0.65-3.25 per IQR-difference of 1.2 μg/m3). Estimated associations for formaldehyde were higher for acute (OR 2.07, 95%CI 0.70-6.12) and myeloid subtypes (OR 1.79, 95%CI 0.64-5.01), and in the 4-km buffer around the industrial facilities (OR 2.78, 95%CI 0.48-16.13), although they remained uncertain.

CONCLUSIONS

This was the first study investigating the link between ambient formaldehyde exposure and leukaemia incidence in the general population. The evidence presented suggests an association, although it remains inconclusive, and a potential significance of emissions related to industrial activities in the district. Further research is warranted in larger populations incorporating data on other potential risk factors.

The increased chromosomal DNA damage in patients with Familial Mediterranean Fever

Familial Mediterranean Fever (FMF) is an inherited autoinflammatory disease. In this study, we aimed to assess chromosomal DNA damage and cell proliferation by using cytokinesis-block micronucleus cytome (CBMN-cyt) assay in the peripheral blood lymphocytes of untreated FMF patients carrying M694V and R202Q mutations, which are the most common MEFV gene mutations in Turkish society. The study included 20 untreated FMF patients with M694V and R202Q mutations and 20 healthy individuals of similar age and sex as the control group. Micronucleus (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) were scored in the obtained bi-nucleated (BN) cells. Additionally, the nuclear division index (NDI) was calculated using the scores of mononuclear, binuclear, and multinuclear cells. We found that MN and NPBs frequencies in FMF patients were significantly higher than in controls, and number of metaphases was significantly lower (respectively, p < 0.05, p < 0.01, and p < 0.01). However, there was no significant difference in NBUDs frequencies and NDI values between FMF patients and controls (p > 0.05). Our study is the first to evaluate FMF patients' lymphocytes using the CBMN-cyt assay, as no previous research has been found in this respect. Increased MN and NPB frequencies may be useful as biomarkers for chromosomal DNA damage, and may indicate a potential for elevated cancer risk in untreated FMF patients.

Modulatory effect of the fruit rind extract of Garcinia indica Choisy against gamma radiation induced damage in human peripheral blood lymphocytes: a preliminary study

PURPOSE

Nowadays people are exposed to radiation due to various reasons, including natural, diagnostic, occupational or accidental exposure. High level of exposure to ionizing radiation can be fatal to human body. Synthetic drugs used to prevent radiation-induced damage are toxic in nature. Recently, Herbal drugs are being screened as an alternative due to their mechanism of action. Garcinia indica (G. indica) is one of the traditional medicinal plant which contains phytochemicals having several medicinal properties.

MATERIALS AND METHODS

In this study, G. indica extract was observed for its modulatory effect against 3 Gray (Gy) gamma radiation-induced damages in human peripheral blood lymphocytes. Various concentrations of G. indica extract ranging from 1 to 25 µg/mL was added to the blood post irradiation at 0 hr. Chromosomal aberration (CA) and Cytochalasin B blocked Micronuclei Cytome (CBMN) Assay were performed as per standard procedure.

RESULTS

Radiomodulatory effect of Garcinia indica fruit rind extract (GIFRE) on CA and MN formation was observed in this study. Treatment of GIFRE did not affect the mitotic index. Positive inhibition percentages for dicentrics, total chromosomal aberrations and micronuclei were observed except for one instance.

CONCLUSION

Owing to the various properties of Garcinia extracts, it makes it a potential candidate to be tested for its radiomodulatory effect. Based on the results observed in this preliminary study, it could act as a radiomodulatory agent. Radiomodulatory effect of GIFRE could possibly serve it as a potential herbal medicinal alternative to current drugs. However, results of this study need to be validated on larger sample size.

Use of micronucleus cytome assays with buccal cells for the detection of genotoxic effects: A systematic review and meta-analysis of occupational exposures to metals

Micronucleus (MN) assays with buccal cells are at present widely used to investigate occupational exposures to genotoxic carcinogens. This article describes their use for the monitoring of metal exposed workers. We found in total 73 relevant articles, in the majority (97 %) increased MN and/or other nuclear anomalies were reported. Most studies were realized in South East Asia and South America. A variety of different occupations was studied including welders, electroplaters, painters, workers in battery recycling and production, tannery workers, dental technicians, miners, workers in foundries and smelters, and also subjects working in waste recycling, glass, aluminum and steel production. In many investigations the effects increased with the duration of the working period. The quality of individual studies was evaluated with a quality score tool. The number of cells was in most studies sufficient and DNA-specific stains were used. However, many studies have shortcomings, e.g. they focused solely on MN formation and did not evaluate anomalies, which provide additional information about the stability of the genetic material and acute cytotoxic effects. Only 35 % of the investigations contain quantitative information about exposures to metals and other toxicants. In 6 of these studies, correlations were observed between the concentrations of specific metals (As, Pb, Cr, Cd) in body fluids and MN frequencies. Taken together, the available data indicate that the MN assay can be used to detect chromosomal damage in metal exposed groups; furthermore, it enables also comparisons between subgroups differing in regard to their exposure and allows an estimation of the efficiency of protective measures. The exposure of workers to metals is currently controlled with chemical analytical measurements only, MN assays with buccal cells could contribute to further improve the safety at workplaces as they reflect the biological consequences including synergistic and antagonistic interactions between toxicants.

Mobile phone specific radiation disturbs cytokinesis and causes cell death but not acute chromosomal damage in buccal cells: Results of a controlled human intervention study

Several human studies indicate that mobile phone specific electromagnetic fields may cause cancer in humans but the underlying molecular mechanisms are currently not known. Studies concerning chromosomal damage (which is causally related to cancer induction) are controversial and those addressing this issue in mobile phone users are based on the use of questionnaires to assess the exposure. We realized the first human intervention trial in which chromosomal damage and acute toxic effects were studied under controlled conditions. The participants were exposed via headsets at one randomly assigned side of the head to low and high doses of a UMTS signal (n = 20, to 0.1 W/kg and n = 21 to 1.6 W/kg Specific Absorption Rate) for 2 h on 5 consecutive days. Before and three weeks after the exposure, buccal cells were collected from both cheeks and micronuclei (MN, which are formed as a consequence of structural and numerical chromosomal aberrations) and other nuclear anomalies reflecting mitotic disturbance and acute cytotoxic effects were scored. We found no evidence for induction of MN and of nuclear buds which are caused by gene amplifications, but a significant increase of binucleated cells which are formed as a consequence of disturbed cell divisions, and of karyolitic cells, which are indicative for cell death. No such effects were seen in cells from the less exposed side. Our findings indicate that mobile phone specific high frequency electromagnetic fields do not cause acute chromosomal damage in oral mucosa cells under the present experimental conditions. However, we found clear evidence for disturbance of the cell cycle and cytotoxicity. These effects may play a causal role in the induction of adverse long term health effects in humans.

Human plasma can modulate micronucleus frequency in TK6 and OE33 cells in vitro

In this paper, we studied the potential genotoxic effects of human plasma from healthy volunteers, as well as patients with gastro-oesophageal reflux disease, Barrett's oesophagus (BO) and oesophageal adenocarcinoma (OAC) using the oesophageal adenocarcinoma cell line (OE33) and the lymphoblastoid cell line (TK6). Both TK6 and OE33 cells were treated with plasma (10 % volume, replacing foetal bovine serum (FBS) or horse serum (HS)) at different time points of 4 h (for the micronucleus (Mn) assay and the invasion assay) and 24 h (for the cell cycle studies). Plasma-induced effects on DNA damage levels, cell viability and the cell cycle were studied by the micronucleus assay, cytokinesis block proliferation index (CBPI) and flow cytometry respectively. The expression of IL-8 in supernatants of TK6 cells and IFN-β in OE33 cells was also analysed by enzyme-linked immunosorbent assay (ELISA). Finally, we carried out an assessment of cellular invasion of OE33 cells following plasma treatment. The results of the micronucleus assay confirmed the genotoxicity of direct plasma treatment from some participants through the increase in DNA damage in TK6 cells. Conversely, some individual patient plasma samples reduced background levels of TK6 cell Mn frequency, in an anti-genotoxic fashion. In TK6 cells, (on average) plasma samples from patients with Barrett's oesophagus induced higher micronucleus levels than healthy volunteers (p= 0.0019). There was little difference in Mn induction when using plasma versus serum to treat the cells in vitro. Cell cycle results showed that direct plasma treatment had a marked impact on OE33 cells at 24 h (p=0.0182 for BO and p=0.0320 for OAC) by decreasing the proportion of cells in the S phase, while plasma exposure was less impactful on the cell cycle of TK6 cells. Invasion of OE33 cells was also seen to be non-significantly affected by plasma treatment of OE33 cells. The addition of N-acetyl cysteine NAC in a dose-dependent matter did not alter the formation of Mn in TK6 cells, suggesting that reactive oxygen species (ROS) are not the root cause of plasma's genotoxicity. The concentration of IL-8 in TK6 cells and IFN-β in OE33 cells was significantly higher in cells treated with OAC-derived plasma than in the untreated negative control. Collectively, our results demonstrate that plasma-specific effects are detectable which helps us better understand some important aspects of the biology of blood-based biomarkers under development.

Micronuclei and other nuclear anomalies in exfoliated urothelial cells and urinary 8-hydroxy-deoxyguanosine levels among Turkish hairdressers

Hairdressers are constantly occupationally exposed to many chemicals have the potential to cause allergies and carcinogenic effects, act as skin and eye irritants and induce oxidative stress and DNA damage. This study aimed to evaluate occupation-induced genotoxicity based on the presence of micronucleus (MN) and other nuclear anomalies in urothelial cells and measure oxidative DNA damage based on the 8-hydroxy-2'-deoxyguanosine level in the urine of Turkish hairdressers. Originality of this study comes from that there was no study on MN and other nuclear anomalies frequencies and oxidative DNA damage in urine samples of hairdressers in the literature. The mean±standard deviation frequency (‰) of micronucleated (MNed) cells was higher in the hairdresser group (n=56) (4.81±7.87, p<0.001) than in the control group (n=56) (0.93±1.85). Nuclear buds were not observed in either group. While the frequency of basal cells was higher in the control group (446.6±106.21) than in the hairdresser group (367.78±101.51, p<0.001), the frequency of binuclear, karyolytic, pycnotic and karyorrhectic cells were higher in the hairdresser group (0.41±0.80, p<0.001; 438.02±118.27, p<0.001; 0.43±0.76, p<0.001; and 47.27±28.40, p<0.001) than in the control group (0.04±0.27, 358.57±95.71, 0.05±0.23 and 24.41±14.50). Condensed chromatins were observed only in the hairdresser group. Specific gravity adjusted 8-hydroxy-2'-deoxyguanosine level was statistically lower in the hairdresser group (908.21±403.25 ng/mL-SG) compared to the control group (1003.09±327.09 ng/mL-SG) (p=0.024). No significant correlation was found between the 8-hydroxy-2'-deoxyguanosine level and the frequency MN. The amount of formaldehyde released during Brazilian keratin treatment was higher than the American Conference of Governmental Industrial Hygienists -Threshold Limit Value (ACGIH-TLV; 0.1 ppm). Similarly, the amount of ethyl acetate released in three salons was above the recommended limit (400 ppm). These findings suggest that hairdressers have an increased risk of genotoxicity and cytotoxicity owing to occupational exposure, regardless of age, working hours, smoking and alcohol consumption.

Exploring cytokinesis block micronucleus assay in Croatia: A journey through the past, present, and future in biomonitoring of the general population

In this study, we used the cytokinesis-block micronucleus (CBMN) assay to evaluate the background frequency of cytogenetic damage in peripheral blood lymphocytes of the general population concerning different anthropometric data and lifestyle factors. The background frequency of CBMN assay parameters was analysed in 850 healthy, occupationally non-exposed male and female subjects (average age, 38±11 years) gathered from the general Croatian population from 2000 to 2023. The mean background values for micronuclei (MNi) in the whole population were 5.3±4.3 per 1000 binucleated cells, while the mean frequency of nucleoplasmic bridges (NPBs) was 0.7±1.3 and of nuclear buds (NBUDs) 3.1±3.2. The cut-off value, which corresponds to the 95th percentile of the distribution of 850 individual values, was 14 MNi, 3 NPBs, and 9 NBUDs. Results from our database also showed an association of the tested genomic instability parameters with age and sex but also with other lifestyle factors. These findings underscore the importance of considering several anthropometric and lifestyle factors when conducting biomonitoring studies. Overall, the normal and cut-off values attained here present normal values for the general population that can later serve as baseline values for further human biomonitoring studies either in Croatia or worldwide.

A review of sources, pathways, and toxic effects of human exposure to benzophenone ultraviolet light filters

Benzophenone ultraviolet light filters (BPs) are high-production-volume chemicals extensively used in personal care products, leading to widespread human exposure. Given their estrogenic properties, the potential health risks associated with exposure to BPs have become a public health concern. This review aims to summarize sources and pathways of exposure to BPs and associated health risks. Dermal exposure, primarily through the use of sunscreens, constitutes a major pathway for BP exposure. At a recommended application rate, dermal exposure of BP-3 via the application of sunscreens may reach or exceed the suggested reference dose. Other exposure pathways to BPs, such as drinking water, seafood, and packaged foods, contribute minimal to the overall dose. Inhalation is a minor pathway of exposure; however, its contribution cannot be ignored. Human exposure to BPs is an order of magnitude higher in North America than in Asia and Europe. Studies conducted on laboratory animals and cells have consistently demonstrated the toxic effects of BP exposure. BPs are estrogenic and elicit reproductive and developmental toxicities. Furthermore, neurotoxicity, hepatotoxicity, nephrotoxicity, and carcinogenicity have been reported from chronic BP exposure. In addition to animal and cell studies, epidemiological investigations have identified associations between BPs and couples' fecundity and other reproductive disorders, as well as adverse birth outcomes. Further studies are urgently needed to understand the risks posed by BPs on human health.

Exposure to microcrystallized cellulose affects the health of tadpoles and sheds light on the threat these materials pose to amphibians

The increasing use of cellulose-based materials (CBMs) has provided beneficial applications in different sectors. However, its release into environments may represent an ecological risk, therefore demanding that ecotoxicological studies be conducted to understand the risks (current and future) of CBM pollution. Thus, we evaluated the possible effects of microcrystalline cellulose (CMs) in Physalaemus cuvieri tadpoles. After seven days of exposure to CMs (at 58.29 and 100 mg/L), the animals were subjected to behavioral evaluation, and different biomarkers (biometric and biochemical) were evaluated. Although our data do not point to a neurotoxic effect of CMs (inferred by the absence of behavioral changes and changes in AChE and BChE activity), animals exposed to CMs showed differences in body condition. Furthermore, we noticed an increase in the frequency of erythrocyte nuclear abnormalities and DNA damage, which were correlated with the ingestion of CMs. We noticed that the antioxidant activity of tadpoles exposed to CMs (inferred by SOD, CAT, and DPPH radical scavenging activity) was insufficient to control the increase in ROS and MDA production. Furthermore, exposure to CMs induced a predominant Th2-specific immune response, marked by suppressed IFN-γ and increased IL-10 levels, with a consequent reduction in NO levels. Principal component analysis and IBRv-2 indicate, in general, a primarily more toxic response to animals exposed to the highest CM concentration. Therefore, our study evidence that CMs affect the health of P. cuvieri tadpoles and sheds light on the threat these materials pose to amphibians.

FEN1 Inhibition as a Potential Novel Targeted Therapy against Breast Cancer and the Prognostic Relevance of FEN1

To improve breast cancer treatment and to enable new strategies for therapeutic resistance, therapeutic targets are constantly being studied. Potential targets are proteins of DNA repair and replication and genomic integrity, such as Flap Endonuclease 1 (FEN1). This study investigated the effects of FEN1 inhibitor FEN1-IN-4 in combination with ionizing radiation on cell death, clonogenic survival, the cell cycle, senescence, doubling time, DNA double-strand breaks and micronuclei in breast cancer cells, breast cells and healthy skin fibroblasts. Furthermore, the variation in the baseline FEN1 level and its influence on treatment prognosis was investigated. The cell lines show specific response patterns in the aspects studied and have heterogeneous baseline FEN1 levels. FEN1-IN-4 has cytotoxic, cytostatic and radiosensitizing effects, expressed through increasing cell death by apoptosis and necrosis, G2M share, senescence, double-strand breaks and a reduced survival fraction. Nevertheless, some cells are less affected by the cytotoxicity and fibroblasts show a rather limited response. In vivo, high FEN1 mRNA expression worsens the prognosis of breast cancer patients. Due to the increased expression in breast cancer tissue, FEN1 could represent a new tumor and prognosis marker and FEN1-IN-4 may serve as a new potent agent in personalized medicine and targeted breast cancer therapy.

Assessment of genotoxic instability markers in peripheral blood lymphocytes of breast cancer patients: a case control study

Changes in genetic constitution of an individual leads to uncontrollable cell growth and tumour formation. The acquisition of genomic instability predisposes cells to accumulate stable genome mutations causing carcinogenesis. The cytokinesis-block micronucleus cytome assay (CBMN), a well-established marker assay for chromosomal mutagen sensitivity, was applied in this study enrolling breast cancer patients and age and sex-matched controls. This work aimed to assess the predictive value of the frequency of genotoxic markers in peripheral blood lymphocytes for the risk/susceptibility of breast cancer. Samples from a hundred untreated breast cancer patients and age and sex matched controls were enrolled in the study from Government Medical College, Alappuzha. The genomic instability was assessed using cytokinesis block micronucleus assay where cytome events were marked. The results showed a significant increase in the frequency of micronucleus, nucleoplasmic bridge, and buds in the binucleated cells of breast cancer patients compared to the control samples. The variability was assessed by CBMN Cyt assay. The frequency of Micronuclei and Nucleoplasmic buds was significantly higher in the patient groups than in the controls (p < 0.0001). In Breast cancer patients, the median (IQR) range of MNi was 12(6), the Nucleoplasmic bridge 3(3) and the Nuclear buds were 2(1) and, in the controls, it was 6(5), 1(2) and 1(1) respectively. A larger difference in the frequency of genetic markers in cancer patients over control cases support a significant role of these markers in the population screening of individuals at high risk of cancer.Communicated by Ramaswamy H. Sarma.

DNA damage in workers exposed to pigment grade titanium dioxide (TiO2) and association with biomarkers of oxidative stress and inflammation

The present study was aimed at investigating DNA damage, micronuclei frequency and meta-nuclear alterations in buccal cells of workers involved in pigment-grade TiO2 production (15 exposed and 20 not-exposed). We also assessed associations of genotoxicity biomarkers with oxidative stress/inflammatory biomarkers in urine and exhaled breath condensate (EBC), as well as possible associations between biomarkers and reported respiratory symptoms. In spite of compliance with TiO2 Occupational Exposure Limits, results showed increased direct/oxidative DNA damage and micronuclei frequency in exposed workers. Genotoxicity parameters were associated with oxidative stress/inflammation biomarkers in urine and EBC, thus confirming that TiO2 exposure can affect the oxidative balance. Workers with higher genotoxic/oxidative stress biomarkers levels reported early respiratory symptoms suggesting that molecular alterations can be predictive of early health dysfunctions. These findings suggest the need to assess early health impairment in health surveillance programs and to address properly safety issues in workplaces where TiO2 is handled.

Occupational exposures and cancer risk in commercial laundry and dry cleaning industries: a scoping review

BACKGROUND

The laundry and dry cleaning industries are critical for maintaining cleanliness and hygiene in our daily lives. However, they have also been identified as sources of hazardous chemical exposure for workers, leading to potentially severe health implications. Despite mounting evidence that solvents like perchloroethylene and trichloroethylene are carcinogenic, they remain commonly used in the industry. Additionally, while alternative solvents are increasingly being utilized in response to indications of adverse health and environmental effects, there remains a significant gap in our understanding of the potential risks associated with exposure to these new agents.

METHODS

This study aims to identify gaps in the literature concerning worker exposure to contemporary toxic chemicals in the laundry and dry cleaning industry and their associated carcinogenic risks. A scoping review of peer-reviewed publications from 2012 to 2022 was conducted to achieve this objective, focusing on studies that detailed chemical exposures, sampling methods, and workers within the laundry and dry cleaning sector.

RESULTS

In this scoping review, 12 relevant papers were assessed. A majority (66%) examined perchloroethylene exposure, with one notable finding revealing that biomarkers from dry cleaners had significant micronuclei frequency and DNA damage, even when exposed to PCE at levels below occupational exposure limits. Similarly, another study supported these results, finding an increase in early DNA damage among exposed workers. Separate studies on TCE and benzene presented varied exposure levels and health risks, raising concern due to their IARC Group 1 carcinogen classification. Information on alternative solvents was limited, highlighting gaps in health outcome data, exposure guidelines, and carcinogenic classifications.

CONCLUSION

Research on health outcomes, specifically carcinogenicity from solvent exposure in dry cleaning, is limited, with 66% of studies not monitoring health implications, particularly for emerging solvents. Further, findings indicated potential DNA damage from perchloroethylene, even below set occupational limits, emphasizing the need to reevaluate safety limits. As alternative solvents like butylal and high-flashpoint hydrocarbons become more prevalent, investigations into the effects of their exposure are necessary to safeguard workers' health. This scoping review is registered with the Open Science Framework, registration DOI: https://doi.org/10.17605/OSF.IO/Q8FR3 .

Determination of the genotoxic effects of sweeteners, mannitol and lactitol

The changes in dietary habit around the world have led to an increased use of additives in the food. The safety of food additives has been a main focus of research for many years due to the ongoing debate on their potential effects on health. In this study, the in vitro genotoxic effects of mannitol and lactitol, polyols used as sweetener food additives, were evaluated using chromosomal aberrations (CAs) and micronucleus (MN) assays in human peripheral lymphocytes. Additionally, the effects of these sweeteners on the mitotic index (MI) and nuclear division index (NDI) were investigated. Concentrations of 500, 1000, 2000, 4000, and 8000 μg/mL for mannitol and 250, 500, 1000, 2000, and 4000 μg/mL for lactitol were used. The results indicated that both polyols did not affect CA and MN frequency, and did not cause a significant change in NDI at all treatment concentratoins. However, mannitol (except at concentrations of 500 and 1000 μg/mL) and lactitol (except at 250 μg/mL) significantly decreased the MI compared to the control at almost all concentrations and treatment times. In conclusion, it was observed that mannitol and lactitol did not have a significant genotoxic effect at the concentrations used in human lymphocytes in vitro.

High-LET charged particles: radiobiology and application for new approaches in radiotherapy

The number of patients treated with charged-particle radiotherapy as well as the number of treatment centers is increasing worldwide, particularly regarding protons. However, high-linear energy transfer (LET) particles, mainly carbon ions, are of special interest for application in radiotherapy, as their special physical features result in high precision and hence lower toxicity, and at the same time in increased efficiency in cell inactivation in the target region, i.e., the tumor. The radiobiology of high-LET particles differs with respect to DNA damage repair, cytogenetic damage, and cell death type, and their increased LET can tackle cells' resistance to hypoxia. Recent developments and perspectives, e.g., the return of high-LET particle therapy to the US with a center planned at Mayo clinics, the application of carbon ion radiotherapy using cost-reducing cyclotrons and the application of helium is foreseen to increase the interest in this type of radiotherapy. However, further preclinical research is needed to better understand the differential radiobiological mechanisms as opposed to photon radiotherapy, which will help to guide future clinical studies for optimal exploitation of high-LET particle therapy, in particular related to new concepts and innovative approaches. Herein, we summarize the basics and recent progress in high-LET particle radiobiology with a focus on carbon ions and discuss the implications of current knowledge for charged-particle radiotherapy. We emphasize the potential of high-LET particles with respect to immunogenicity and especially their combination with immunotherapy.

Do hairdressers comprise a high risk group for genotoxicity? A systematic review

BACKGROUND AND OBJECTIVES

Nowadays, hair dye products are widely used for aesthetic purposes, in which it generates chemical exposure to customers and, mainly, hairdressers. The aim of this systematic review was designed to elucidate the following question: are hair dye products able to induce DNA damage in hairdressers?

METHODS

Studies were included in our analyses if they met the following criteria: (1) studies measuring genetic damage in vivo; (2) studies published in English; (3) studies that provided data clearly presented in scientific standards.

RESULTS

Full manuscripts from 13 studies were carefully selected in this setting. Our results demonstrate that hair dye products may contain chemical agents able to induce DNA strand breaks or chromosome damage since the majority of studies demonstrated positive findings for genotoxicity. A total of 7 studies (out of 13) had strong or moderate rates in the quality assessment. The type of genotoxicity assay and sample selection criteria time influenced the outcome.

CONCLUSION

In summary, our results reveal that hairdressers are occupationally exposed to genotoxic agents. Such findings are very important for protecting these professionals who are continuously exposed to chemicals for long periods.

Micronuclei in human peripheral blood and bone marrow as genotoxicity markers: A systematic review and meta-analysis

Can human peripheral blood cells be used as a surrogate for bone marrow cells, in evaluating the genotoxic effects of stressors? We searched the Pubmed/Medline and PubChem databases to identify publications relevant to this question. Micronucleus formation was the genotoxicity endpoint. Three publications comparing exposed vs. non-exposed individuals are included in this analysis; the exposures were to ethylene oxide or ionising radiation (atomic bomb, thorotrast, or radioiodine therapy). Information was extracted on the types of exposure, the numbers of participants, and the micronucleus frequencies. Relative differences (odds ratios) and absolute differences (risk differences) in the numbers of micronuclei between exposed and non-exposed persons were calculated separately for individual cell types (peripheral blood and bone marrow). Random effects meta-analyses for the relative differences in cell abnormalities were performed. The results showed very small differences in the frequencies of micronuclei between exposed and non-exposed individuals, as measured in either peripheral blood or bone marrow cell populations, on both absolute and relative scales. No definite conclusion concerning the relative sensitivities of bone marrow and peripheral blood cells can be made, based on these publications.

Cytotoxic and genotoxic profiles of the pyrethroid insecticide lambda-cyhalothrin and its microformulation Karate® in CHO-K1 cells

Lambda-cyhalothrin (LCT) and its microformulation Karate® (25 % a.i.) were analysed for its genotoxicity and cytotoxicity on Chinese hamster ovary (CHO-K1) cells. Cytokinesis-block micronucleus cytome (CBMN-cyt) and alkaline single-cell gel electrophoresis (SCGE) bioassays were selected to test genotoxicity. Neutral red uptake (NRU), succinic dehydrogenase activity (MTT) and apoptogenic induction were employed for estimating cytotoxicity. Both compounds were analysed within a concentration range of 0.1-100 µg/mL. Only LCT produced a significant augment in the frequency of micronuclei (MNs) when the cultures were exposed to highest concentrations of 10 and 100 µg LCT/mL. A noticeable decrease in NDI was observed for cultures treated with LCT at 10 and 100 µg/mL. Karate® induced the inhibition of both the proportion of viable cells and succinic dehydrogenase activity and triggered apoptosis 24 h of exposition. Whilst an increased GDI in CHO-K1 cells was observed in the treatments with 1-100 µg Karate®/mL, the GDI was not modified in the treatments employing LCT at equivalent doses. SCGE showed that Karate® was more prone to induce genotoxic effects than LCT. Only 50 µg/mL of Karate® was able to increase apoptosis. Our results demonstrate the genomic instability and cytotoxic effects induced by this pyrethroid insecticide, confirming that LCT exposure can result in a severe drawback for the ecological equilibrium of the environment.

Lymnaea stagnalis and Ophryotrocha diadema as Model Organisms for Studying Genotoxicological and Physiological Effects of Benzophenone-3

Benzophenone-3 (BP-3) is a lipophilic organic compound that occurs naturally in flower pigments. Since it adsorbs ultraviolet (UV) radiation in the UVA and UVB regions, it is one of the most common UV filters found in sunscreen and cosmetic products. We explored by in vivo micronuclei (MNi) assay the genotoxic effects of BP-3 on hemocytes from the freshwater gastropod Lymnaea stagnalis. We also studied its possible toxic effects on life-history traits: body growth in L. stagnalis and egg production of both L. stagnalis and the marine polychaete worm Ophryotrocha diadema. Adult individuals were exposed to increasing concentrations of BP-3 (0.025, 0.050, 0.100, and 0.200 mg/L) once a week for 4 weeks. In L. stagnalis, exposure to BP-3 at concentrations of both 0.2 and 0.1 mg/L produced genotoxic effects on the micronuclei frequencies, but only concentrations of 0.2 mg/L affected the NBUDs frequencies. Similarly, negative effects on body growth were observed at the concentrations of 0.2 and 0.1 mg/L and a significant reduction of egg production at 0.2 mg/L. In O. diadema, a negative correlation between egg production and increasing BP-3 concentrations was observed. Our findings suggest the need for more stringent measures to reduce the presence of BP-3 in the environment.

Increased oxidative and chromosomal DNA damage in patients with ankylosing spondylitis: its role in pathogenesis

Increased DNA damage has been suggested to contribute to the pathogenesis of chronic inflammatory diseases, but controlled studies are lacking in ankylosing spondylitis (AS). Therefore, we assessed oxidative stress, oxidative DNA damage, chromosomal DNA damage, cell proliferation and cell death in the peripheral blood lymphocytes of patients with AS as well as the possible role of DNA damage in the development of the disease. In total, 25 newly diagnosed AS patients who had not received anti-inflammatory agents and 25 healthy controls were recruited. Oxidative DNA damage was assessed by plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, and chromosomal DNA damage was assessed by the cytokinesis-block micronucleus cytome (CBMN-cyt) method. Compared to controls, the micronucleus (MN) frequencies, nucleoplasmic bridge (NPB) frequencies, nuclear bud (NBUD) frequencies, apoptotic cell frequencies, necrotic cell frequencies and plasma 8-OHdG levels were significantly higher in patients with AS (p < 0.001, p < 0.05, p < 0.01, p < 0.001, p < 0.001, and p < 0.001, respectively), and the metaphase cell numbers, binucleated (BN) cell frequencies and nuclear division index (NDI) values were significantly lower in patients with AS (p < 0.01, p < 0.001 and p < 0.001, respectively). Thus, the present findings suggested that oxidative stress, oxidative DNA damage, and chromosomal DNA damage may be involved in the pathogenesis of AS similar to other chronic inflammatory diseases. In addition, the increased plasma 8-OHdG levels, MN frequencies, NPB frequencies and NBUD frequencies in AS patients may reflect an increased cancer risk.

Quality Control Optimization for Minimizing Security Risks Associated with Mesenchymal Stromal Cell-Based Product Development

Mesenchymal stromal cells (MSCs) have been considered a therapeutic strategy in regenerative medicine because of their regenerative and immunomodulatory properties. The translation of MSC-based products has some challenges, such as regulatory and scientific issues. Quality control should be standardized and optimized to guarantee the reproducibility, safety, and efficacy of MSC-based products to be administered to patients. The aim of this study was to develop MSC-based products for use in clinical practice. Quality control assays include cell characterization, cell viability, immunogenicity, and cell differentiation; safety tests such as procoagulant tissue factor (TF), microbiological, mycoplasma, endotoxin, genomic stability, and tumorigenicity tests; and potency tests. The results confirm that the cells express MSC markers; an average cell viability of 96.9%; a low expression of HLA-DR and costimulatory molecules; differentiation potential; a high expression of TF/CD142; an absence of pathogenic microorganisms; negative endotoxins; an absence of chromosomal abnormalities; an absence of genotoxicity and tumorigenicity; and T-lymphocyte proliferation inhibition potential. This study shows the relevance of standardizing the manufacturing process and quality controls to reduce variability due to the heterogeneity between donors. The results might also be useful for the implementation and optimization of new analytical techniques and automated methods to improve safety, which are the major concerns related to MSC-based therapy.

Twenty years of merotelic kinetochore attachments: a historical perspective

Micronuclei, small DNA-containing structures separate from the main nucleus, were used for decades as an indicator of genotoxic damage. Micronuclei containing whole chromosomes were considered a biomarker of aneuploidy and were believed to form, upon mitotic exit, from chromosomes that lagged behind in anaphase as all other chromosomes segregated to the poles of the mitotic spindle. However, the mechanism responsible for inducing anaphase lagging chromosomes remained unknown until just over twenty years ago. Here, I summarize what preceded and what followed this discovery, highlighting some of the open questions and opportunities for future investigation.

Assessment of radiation doses and DNA damage in pediatric patients undergoing interventional procedures for vascular anomalies

Interventional procedures (IPs) have been widely used to treat vascular anomalies (VA) in recent years. However, patients are exposed to low-dose X-ray ionizing radiation (IR) during these fluoroscopy-guided IPs. We collected clinical information and IR doses during IPs and measured biomarkers including γ-H2AX, chromosome aberrations (CA), and micronuclei (MN), which underpin radiation-induced DNA damage, from 74 pediatric patients before and after IPs. For the 74 children, the range of dose-area product (DAP) values was from 1.2 to 1754.6 Gy∙cm², with a median value of 27.1 Gy∙cm². DAP values were significantly higher in children with lesions in the head and neck than in the limbs and trunk; the age and weight of children revealed a strong positive correlation with DAP values. The treated patients as a group demonstrated an increase in all three endpoints relative to baseline following IPs. Children with vascular tumors have a higher risk of dicentric chromosome + centric ring (dic+r) and cytokinesis-block micronucleus (CBMN) after IPs than children with vascular malformations. The younger the patient, the greater the risk of CA after IPs. Moreover, rogue cells (RCs) were found in five children (approximately 10%) after IPs, and the rates of dic+r and CBMN were significantly higher than those of other children (Z = -3.576, p < 0.001). These results suggest that there may be some children with VA who are particularly sensitive to IR, but more data and more in-depth experiments will be needed to verify this in the future.

Exposure to nanoplastic particles and DNA damage in mammalian cells

There is concern about human exposure to nanoplastics from intentional use or degradation of plastics in the environment. This review assesses genotoxic effects of nanoplastics, defined as particles with a primary size of less than 1000 nm. The majority of results on genotoxicity come from studies on polystyrene (PS) particles in mammalian cell cultures. Most studies have measured DNA strand breaks (standard comet assay), oxidatively damaged DNA (Fpg-modified comet assay) and micronuclei. Twenty-nine out of 60 results have shown statistically significant genotoxic effects by PS exposure in cell cultures. A statistical analysis indicates that especially modified PS particles are genotoxic (odds ratio = 8.6, 95 % CI: 1.6, 46) and immune cells seems to be more sensitive to genotoxicity than other cell types such as epithelial cells (odds ratio = 8.0, 95 % CI: 1.6, 39). On the contrary, there is not a clear association between statistically significant effects in genotoxicity tests and the primary size of PS particles, (i.e. smaller versus larger than 100 nm) or between the type of genotoxic endpoint (i.e. repairable versus permanent DNA lesions). Three studies of PS particle exposure in animals have shown increased level of DNA strand breaks in leukocytes and prefrontal cortex cells. Nanoplastics from polyethylene, propylene, polyvinyl chloride and polyethylene terephthalate have been investigated in very few studies and it is currently not possible to draw conclusion about their genotoxic hazard. In summary, there is some evidence suggesting that PS particles may be genotoxic in mammalian cells.

Genotoxicity and endocrine disruption potential of haloacetic acids in human placental and lung cells

Chlorination of water results in the formation of haloacetic acids (HAAs) as major disinfection byproducts (DBPs). Previous studies have reported some HAAs species to act as cytotoxic, genotoxic, and carcinogenic. This work aimed at further exploring the toxicity potential of the most investigated HAAs (chloroacetic (CAA), bromoacetic (BAA), iodoacetic (IAA) acid) and HAAs species with high content of bromine (tribromoacetic acid (TBAA)), and iodine in their structures (chloroiodoacetic (CIAA) and diiodoacetic acid (DIAA)) to human cells. Novel knowledge was generated regarding cytotoxicity, oxidative stress, endocrine disrupting potential, and genotoxicity of these HAAs by using human placental and lung cells as in vitro models, not previously used for DBP assessment. IAA showed the highest cytotoxicity (EC₅₀: 7.5 μM) and ability to generate ROS (up to 3-fold) in placental cells, followed by BAA (EC₅₀: 20-25 μM and 2.1-fold). TBAA, CAA, DIAA, and CIAA showed no significant cytotoxicity (EC₅₀ > 250 μM). All tested HAAs decreased the expression of the steroidogenic gene hsd17b1 up to 40 % in placental cells, and IAA and BAA (0.01-1 μM) slightly inhibited the aromatase activity. HAAs also induced the formation of micronuclei in A549 lung cells after 48 h of exposure. IAA and BAA showed a non-significant increase in micronuclei formation at low concentrations (1 μM), while BAA, CAA, CIAA and TBAA were genotoxic at exposure concentrations above 10 μM (100 μM in the case of DIAA). These results point to genotoxic and endocrine disruption effects associated with HAA exposure at low concentrations (0.01-1 μM), and the usefulness of the selected bioassays to provide fast and sensitive responses to HAA exposure, particularly in terms of genotoxicity and endocrine disruption effects. Further studies are needed to define thresholds that better protect public health.

Establishment of ex vivo calibration curve for X-ray induced "dicentric + ring" and micronuclei in human peripheral lymphocytes for biodosimetry during radiological emergencies, and validation with dose blinded samples

In the modern developing society, application of radiation has increased extensively. With significant improvement in the radiation protection practices, exposure to human could be minimized substantially, but cannot be avoided completely. Assessment of exposure is essential for regulatory decision and medical management as applicable. Until now, cytogenetic changes have served as surrogate marker of radiation exposure and have been extensively employed for biological dose estimation of various planned and unplanned exposures. Dicentric Chromosomal Aberration (DCA) is radiation specific and is considered as gold standard, micronucleus is not very specific to radiation and is considered as an alternative method for biodosimetry. In this study dose response curves were generated for X-ray induced "dicentric + ring" and micronuclei, in lymphocytes of three healthy volunteers [2 females (age 22, 23 years) and 1 male (24 year)]. The blood samples were irradiated with X-ray using LINAC (energy 6 MV, dose rate 6 Gy/min), in the dose range of 0-5Gy. Irradiated blood samples were cultured and processed to harvest metaphases, as per standard procedures recommended by International Atomic Energy Agency. Pooled data obtained from all the three volunteers, were in agreement with Poisson distribution for "dicentric + ring", however over dispersion was observed for micronuclei. Data ("dicentric + ring" and micronuclei) were fitted by linear quadratic model of the expression Y[bond, double bond]C + αD + βD² using Dose Estimate software, version 5.2. The data fit has resulted in linear coefficient α = 0.0006 (±0.0068) "dicentric + ring" cell^-1 Gy^-1 and quadratic coefficient β = 0.0619 (±0.0043) "dicentric + ring" cell^-1 Gy^-2 for "dicentric + ring" and linear coefficient α = 0.0459 ± (0.0038) micronuclei cell^-1 Gy^-1 and quadratic coefficient β = 0.0185 ± (0.0010) micronuclei cell^-1 Gy^-2 for micronuclei, respectively. Background frequencies for "dicentric + ring" and micronuclei were 0.0006 ± 0.0004 and 0.0077 ± 0.0012 cell^-1, respectively. Established curves were validated, by reconstructing the doses of 8 dose blinded samples (4 by DCA and 4 by CBMN) using coefficients generated here. Estimated doses were within the variation of 0.9-16% for "dicentric + ring" and 21.7-31.2% for micronuclei respectively. These established curves have potential to be employed for biodosimetry of occupational, clinical and accidental exposures, for initial triage and medical management.

Citrinin as a potential anti-cancer therapy: A comprehensive review

Citrinin (CIT) is a polyketide-derived mycotoxin, which is produced by many fungal strains belonging to the gerena Monascus, Aspergillus, and Penicillium. It has been postulated that mycotoxins have several toxic mechanisms and are potentially used as antineoplastic agents. Therefore, the present study carried out a systematic review, including articles from 1978 to 2022, by collecting evidence in experimental studies of CIT antiplorifactive activity in cancer. The Data indicate that CIT intervenes in important mediators and cell signaling pathways, including MAPKs, ERK1/2, JNK, Bcl-2, BAX, caspases 3,6,7 and 9, p53, p21, PARP cleavage, MDA, reactive oxygen species (ROS) and antioxidant defenses (SOD, CAT, GST and GPX). These factors demonstrate the potential antitumor drug CIT in inducing cell death, reducing DNA repair capacity and inducing cytotoxic and genotoxic effects in cancer cells.

The influence of vitamin D supplementation and strength training on health biomarkers and chromosomal damage in community-dwelling older adults

Older adults lack of proper physical activity which is often accompanied by vitamin D deficiency. Those factors are known to contribute to health issues in the later years of life. The main goal of this intervention study was to investigate the effect of different vitamin D supplementation strategies for 4 weeks solely or combined with a 10-week strength training program on chromosomal stability in peripheral blood mononuclear cells in community-dwelling older people. One hundred women and men (65-85 years) received either vitamin D3 daily (800 IU), a monthly dose (50.000 IU) or placebo for 17 weeks. All groups received 400 mg calcium daily. The fitness status of the study participants was measured using the 30- second chair stand test, the handgrip strength test and the 6-min walk test. The cytokinesis block micronucleus cytome (CBMN) assay was applied to analyze chromosomal anomalies, including cytotoxic and genotoxic parameters. Changes in antioxidant markers were measured in plasma. Walking distance and chair stand performance improved significantly. Increased levels of the parameters of the CBMN assay were detected for all intervention groups at study end. At baseline micronuclei (MNi) frequency correlated significantly with BMI in both sexes (females: r = 0.369, p = 0.034; males: r = 0.265, p = 0.035), but not with vitamin D serum levels. In females, body fat (r = 0.372, p < 0.001) and functional parameter using the 30-s chair stand test (r = 0.311, p = 0.002) correlated significantly with MNi frequency. Interestingly, not vitamin D supplementation but 10 weeks of resistance training increased MNi frequency indicating elevated chromosomal instability and also adverse effects on antioxidant markers including glutathione and FRAP were detected in the group of community-dwelling older adults.

Phytochemical Analysis and Genotoxicological Evaluation of Prickly Pear Peel Extracts

This study investigated the beneficial properties of prickly pear peel (PPP) extracts from Opuntia ficus-indica (L.) Mill. Extracts were obtained via the Soxhlet extraction method using methanol (P1), ethanol (P2) and ethanol-water (P3) as extraction solvents. Their total phenolic and flavonoid content (TPC and TFC, respectively) and their antioxidant activity (AA) were determined. The PPP extracts were characterized in detail using mass spectrometry techniques. Their cyto-genotoxic effect and antigenotoxic potential against mitomycin C were evaluated via the cytokinesis block micronucleus (CBMN) assay on human lymphocytes. Enhanced TPC, TFC and AA values were recorded for all the extracts. Moreover, P1 and P2 were cytotoxic only at the highest concentrations, whereas P3 was found to be cytotoxic in all cases. No significant micronucleus induction was observed in the tested extracts. The PPP extracts contain bioactive compounds such as flavonoids, carboxylic acids, alkaloids, fatty acids and minerals (mainly K, Si, Mg, Ca, P and Zn). The results showed that all three extracts exerted high antigenotoxic activity. Our findings confirm the beneficial and genoprotective properties of PPP extracts and further studies on the bioactive compounds of Opuntia ficus-indica (L.) Mill. are recommended, as it constitutes a promising plant in pharmaceutical applications.

A comprehensive overview of genotoxicity and mutagenicity associated with outdoor air pollution exposure in Brazil

This review examined the mutagenicity and genotoxicity associated with exposure to outdoor air pollutants in Brazil. A search was performed on the Web of Science database using a combination of keywords that resulted in 134 articles. After applying exclusion criteria, a total of 75 articles were obtained. The articles were classified into three categories: (1) studies with plants and animals, (2) in vitro studies, and (3) human biomonitoring. The investigations were conducted in 11 of 27 Brazilian states with the highest prevalence in the southeast and south regions. Only 5 investigations focused on the effects of burning biomass on the quality of outdoor air. Plants, especially Tradescantia pallida, were the main air pollution biomonitoring tool. When available, a significant association between levels of air pollutants and genetic damage was described. Among the in vitro studies, Salmonella/microsome is the most used test to evaluate mutagenesis of outdoor air in Brazil (n = 26). Human biomonitoring studies were the least frequent category (n = 18). Most of the investigations utilized micronucleus bioassay, in oral mucosa cells (n = 15) and lymphocytes (n = 5), and the comet assay (n = 6). The analysis in this study points to the existence of gaps in genotoxicity studies and our findings indicate that future studies need to address the variety of potential sources of pollution existing in Brazil. In addition to extent of the impacts, consideration should be given to the enormous Brazilian biodiversity, as well as the determination of the role of socioeconomic inequality of the population in the observed outcomes.

Beneficial properties of Drimia numidica leaf methanolic extract against the cytogenotoxic effects of mitomycin C on human lymphocytes

This study investigated the phytochemical profile of Drimia numidica leaf methanolic extract, as well as its cyto-genotoxic and cyto/genoprotective potential against mitomycin C (MMC) mediated effects on healthy human lymphocytes. Photosynthetic pigments, trace elements, and secondary metabolites were estimated and/or identified in methanolic extract of mature leaves, and the latter was further used for assessing its in vitro biological effects on MMC-free and/or MMC-treated human lymphocytes (at low, non-toxic concentrations of 0.001 and 0.01% v/v). The results showed that D. numidica leaf methanolic extract, being rich in carotenoids, phenolics, flavonoids, organic acids and bufadienolides, could be protective against MMC mediated cyto/genotoxic potential in healthy human lymphocytes. Biomolecules possessing antioxidant and antitumor potential, such as beta-carotene and lutein among others, chlorogenic acid, caffeic acid and their derivatives, minerals such as Si, as well as apigenin- and luteolin-derived glycosides, either individual or in a mixture, could be beneficial rather than harmful, at least at the extract concentrations tested. Although further in vitro and in vivo studies are still needed for elucidating the beneficial (individual and/or additive/synergistic) role of those compounds, the results of the present study are quite promising, thus encouraging new challenges for the appropriate utilization of D. numidica leaf extract.

Re-evaluation of CBMN test reference values of persons continuously occupationally exposed to low doses of ionizing radiation in Serbia

When established, cytokinesis-block micronucleus (CBMN) test reference values should be periodically evaluated according to the recommendations of reference documents. The biodosimetry cytogenetic laboratory of the Serbian Institute of Occupational Health established the CBMN test reference range for people occupationally exposed to ionizing radiation in 2016. Since then, new occupationally exposed persons have been subjected to micronucleus testing, resulting in the need for re-evaluation of existing CBMN test values. The examined population comprised 608 occupationally exposed subjects - 201 from the previous laboratory database and 407 newly examined. Comparison of groups based on gender, age and cigarette consumption did not show significant differences, although certain CBMN values differed significantly between the old and new groups. Duration of occupational exposure, gender, age and smoking habit influenced micronuclei frequency in all three analyzed groups, while no relation was found between type of work and micronucleus test parameters. Since the mean values of all tested parameters in the new group of examinees are within previously established reference ranges, existing values can be used in further research.

Replication stress drives chromosomal instability in fibroblasts of childhood cancer survivors with second primary neoplasms

New development and optimization of oncologic strategies are steadily increasing the number of long-term cancer survivors being at risk of developing second primary neoplasms (SPNs) as a late consequence of genotoxic cancer therapies with the highest risk among former childhood cancer patients. Since risk factors and predictive biomarkers for therapy-associated SPN remain unknown, we examined the sensitivity to mild replication stress as a driver of genomic instability and carcinogenesis in fibroblasts from 23 long-term survivors of a pediatric first primary neoplasm (FPN), 22 patients with the same FPN and a subsequent SPN, and 22 controls with no neoplasm (NN) using the cytokinesis-block micronucleus (CBMN) assay. Mild replication stress was induced with the DNA-polymerase inhibitor aphidicolin (APH). Fibroblasts from patients with the DNA repair deficiency syndromes Bloom, Seckel, and Fanconi anemia served as positive controls and for validation of the CBMN assay supplemented by analysis of chromosomal aberrations, DNA repair foci (γH2AX/53BP1), and cell cycle regulation. APH treatment resulted in G2/M arrest and underestimation of cytogenetic damage beyond G2, which could be overcome by inhibition of Chk1. Basal micronuclei were significantly increased in DNA repair deficiency syndromes but comparable between NN, FPN, and SPN donors. After APH-induced replication stress, the average yield of micronuclei was significantly elevated in SPN donors compared to FPN (p = 0.013) as well as NN (p = 0.03) donors but substantially lower than for DNA repair deficiency syndromes. Our findings suggest that mild impairment of the response to replication stress induced by genotoxic impacts of DNA-damaging cancer therapies promotes genomic instability in a subset of long-term cancer survivors and may drive the development of an SPN. Our study provides a basis for detailed mechanistic studies as well as predictive bioassays for clinical surveillance, to identify cancer patients at high risk for SPNs at first diagnosis.

Impact of Extended and Combined Exposure of Bisphenol Compounds on Their Chromosome-Damaging Effect─Increased Potency and Shifted Mode of Action

Bisphenol (BP) compounds are important environmental pollutants and endocrine disruptors. BPs are capable of inducing DNA/chromosome breaks (clastogenesis, involved in carcinogenesis), which requires activation by human CYP1A1. We hypothesized that combined BPs and extended (from the standard two-cell cycle) exposure may enhance their genotoxicity via modulating CYP enzymes. In this study, individual and combined BPA/BPF/BPS/BPAF and a human hepatoma (HepG2) cell line were used for testing several genotoxicity end points. Exposing for a two-cell cycle period (48 h), each BP alone (0.625-10 μM) was negative in the micronucleus test, while micronucleus was formed under three- (72 h) and four-cell cycle (96 h) exposure; BP combinations further elevated the potency (with nanomolar thresholds). Immunofluorescence analysis of the centromere with formed micronucleus indicated that 48 h exposure produced centromere-negative micronucleus and phosphorylated histone H2AX (γ-H2AX) (evidencing clastogenesis), while extended (72 and 96 h) exposure formed centromere-positive micronucleus and phosphorylated histone H3 (p-H3) (indicating chromosome loss, i.e., aneugenesis); moreover, 1-aminotriabenzotriazole (CYP inhibitor) selectively blocked the formation of centromere-negative micronucleus and γ-H2AX, without affecting that of centromere-positive micronucleus and p-H3. This study suggests that the genotoxicity of BPs is potentiated by combined and extended exposure, the latter being specific for aneuploidy formation, a CYP activity-independent effect.

Sub-chronic oral toxicity evaluation of herbo-metallic formulation Arshakuthar rasa in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Arshakuthar rasa (AR) is a mercury based Ayurvedic herbo-metallic formulation. The concerns are being raised about the probable toxicity of mercury after prolonged use of AR. Hence, there is need for a long-term repeated in vivo toxicity study. The study will provide data with scientific evidence to enable safe use of the drug. Moreover, lack of toxicity study with AR incited us to perform sub-chronic study on rats.

AIM OF THE STUDY

The aim of the study is to generate data by performing a sub-chronic study to assess the toxicity of AR after its prolonged oral intake.

MATERIALS AND METHODS

The female and male rats were administered with 30 (low), 300 (medium) and 600 mg/kg BW/day (high) dose of AR for 90 consecutive days. The body weight, feed consumption and water intake were monitored weekly. On 91^st day, blood was collected from retro-orbital plexus of rats and then sacrificed to harvest the vital organs for biochemical, haematological, histopathological, genotoxicity along with the expression study of oxidative stress related genes and the biodistribution of elements in the blood.

RESULTS

Significant alterations in serum biochemical parameters were observed at the medium and high doses. The histopathological changes were in corroboration with biochemical changes at high dose in liver. There was no detectable level of mercury in blood, less to moderate biochemical changes, no haematological changes, moderate regulation of stress-related genes, and low genotoxicity. These results indicated that AR can be considered as moderately toxic above 600 mg/kg BW and mildly toxic at 300 mg/kg BW.

CONCLUSIONS

It may be interpreted that AR may not induce grave toxic response in human after long-duration of oral administration at therapeutic doses.

Associating Air Pollution with Cytokinesis-Block Micronucleus Assay Parameters in Lymphocytes of the General Population in Zagreb (Croatia)

Air pollution is recognized as one of the most serious public health issues worldwide and was declared to be a leading environmental cause of cancer deaths. At the same time, the cytokinesis-block micronucleus (CBMN) assay serves as a cancer predictive method that is extensively used in human biomonitoring for populations exposed to environmental contamination. The objective of this cross-sectional study is two-fold: to evaluate genomic instability in a sample (N = 130) of healthy, general population residents from Zagreb (Croatia), chronically exposed to different levels of air pollution, and to relate them to air pollution levels in the period from 2011 to 2015. Measured frequencies of CBMN assay parameters were in agreement with the baseline data for the general population of Croatia. Air pollution exposure was based on four factors obtained from a factor analysis of all exposure data obtained for the examined period. Based on the statistical results, we did not observe a significant positive association between any of the CBMN assay parameters tested and measured air pollution parameters for designated time windows, except for benzo(a)pyrene (B[a]P) that showed significant negative association. Our results show that measured air pollution parameters are largely below the regulatory limits, except for B[a]P, and as such, they do not affect CBMN assay parameters’ frequency. Nevertheless, as air pollution is identified as a major health threat, it is necessary to conduct prospective studies investigating the effect of air pollution on genome integrity and human health.

Genoprotective activity of the Pleurotus eryngii mushrooms following their in vitro and in vivo fermentation by fecal microbiota

Pleurotus eryngii mushrooms are commercially cultivated and widely consumed due to their organoleptic properties, and the low caloric and high nutritional value. In addition, they contain various biologically active and health-promoting compounds; very recently, their genoprotective effect in Caco-2 cells after their fermentation by the human fecal microbiota was also documented. In the current study, the effect of P. eryngii pre- and post-fermentation supernatants in micronuclei formation was evaluated in human lymphocytes. In addition, the genoprotective properties of increasing concentrations of aqueous extracts from P. eryngii mushrooms (150, 300, 600 mg/kg) against the cyclophosphamide-induced DNA damage were studied in young and elderly female and male mice in bone marrow and whole blood cells. The ability of the highest dose (600 mg/kg) to regulate the main cellular signaling pathways was also evaluated in gut and liver tissues of female animals by quantifying the mRNA expression of NrF2, Nfkβ, DNMT1, and IL-22 genes. P. eryngii post-fermentation, but not pre-fermentation, supernatants were able to protect human lymphocytes from the mitomycin C-induced DNA damage in a dose-dependent manner. Similarly, genoprotection was also observed in bone marrow cells of mice treated by gavage with P. eryngii extract. The effect was observed in all the experimental groups of mice (young and elderly, male and female) and was more potent in young female mice. Overexpression of all genes examined was observed in both tissues, mainly among the elderly animals. In conclusion, P. eryngii mushrooms were shown to maintain genome integrity through protecting cells from genotoxic insults. These beneficial effects can be attributed to their antioxidant and immunomodulatory properties, as well as their ability to regulate the cell's epigenetic mechanisms and maintain cell homeostasis.