PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Comet assay”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

7 recordsLinked to original sources
PubMed2026

Genotoxicity  effects in Cancer Patients: Evaluation by Micronucleus and Comet Assays and Correlation with Biochemical and Hematological Indices.

BACKGROUND: Cancer is one of the most significant global health challenges. Cytogenetic techniques are used as biomarkers of cancer risk to detect DNA damage and chromosomal abnormalities. OBJECTIVE: This study aimed to evaluate the influence of chemotherapy on genetic stability in cancer patients by applying Micronucleus and Comet assays as indicators of DNA and chromosomal alterations. It also aimed to determine the possible links between these genotoxic changes and variations in biochemical and hematological parameters, providing insight into the cellular responses to chemotherapy exposure. METHODS: Buccal epithelial cells were collected from 190 individuals (90 controls and 100 cancer patients) and stained for micronucleus analysis. To observe DNA breakdown, cells from blood were subjected to an alkaline comet assay. Biochemical (urea, creatinine, calcium, and bilirubin) and hematopoietic (Hb, WBC, Plt, and HCT) parameters were also assessed. RESULTS: Cancer patients showed elevated Binucleated cells (27.50 ± 3.62 per 1000 cells, ~6.8-fold), Condensed chromatin (10.50 ± 2.87 per 1000 cells, ~1.3-fold), pyknotic cells (2.65 ± 1.53 per 1000 cells, ~1.6-fold), basal cells (4.65 ± 1.98 per 1000 cells, ~2.4-fold), Karyorrhectic cells (9.45 ± 1.73 per 1000 cells, ~189-fold), Karyolytic cells (85.10 ± 2.69 per 1000 cells, ~8.9-fold), Monoonucleated cell with Micronucleus (12.50 ± 1.43 per 1000 cells, ~8.3-fold), and Percentage of nuclear anomalies in total (152.8 ± 4.75 per 1000 cells) compared with controls. The comet assay results revealed pronounced DNA fragmentation in cancer cells, with variable tail lengths indicating heterogeneous damage. The biochemical results showed a significant increase in the mean levels of urea (50.600 ± 8.259) and creatinine (1.073 ± 0.173), and no significant increase in TSB (0.917 ± 0.143) and HCT(38.080 ± 2.311) in cancer patients compared to the control. Calcium (9.010 ± 0.680), Hb (8.322 ± 1.247), Plt (91.300 ± 24.495), and WBC (11.920 ± 2.833) levels were lower in the patient group than in the control group. CONCLUSION: The increased frequency of nuclear anomalies and DNA fragmentation in cancer patients highlights the potential of the buccal Micronucleus assay and comet assays as effective, non-invasive tools for early cancer detection and genotoxic monitoring. Alterations in the blood and biochemical parameters further support the systemic effects of malignancy.

Humans↗
PubMed2026

Comet assay analysis of multigenerational genomic instability (F0-F2) in Aedes aegypti exposed to gamma radiation in Sterile Insect Technique.

The use of irradiation in the Sterile Insect Technique (SIT) is a sustainable and environmentally friendly strategy for controlling Aedes aegypti populations by the release of sterile males. However, the potential toxic effects of radiation on mosquito genetic material, as well as the heritability of such damage, remain insufficiently understood. In this study, we evaluated gamma radiation-induced DNA damage (20, 30, 40, and 50 Gy) in male pupae (F0 generation) and assessed the persistence of these effects in subsequent generations (F1 and F2) using the comet assay in hemocytes. In the parental generation, a significant dose-response relationship was observed, with increasing radiation doses associated with higher damage index and damage frequency (p < 0.05). In the F1 generation, both larvae and adults exhibited significantly greater DNA damage than the control group, particularly at doses of 30 and 40 Gy, supporting the inheritance of radiation-induced genomic instability. In the F2 generation, genotoxic effects were attenuated, although residual damage remained detectable in adults, suggesting partial recovery of genomic stability, possibly influenced by DNA repair mechanisms and/or selective pressures. No viable offspring were obtained at 50 Gy, confirming the sterilizing efficacy of higher doses. Integration of comet assay results with micronucleus data and reproductive parameters reinforces the association between DNA damage, mutagenic effects, and reduced fertility. These findings indicate that radiation-induced genotoxic effects may persist beyond the irradiated generation but tend to decline across generations. Overall, this study provides insights into the balance between achieving sterility and preserving biological quality in SIT programs, contributing to optimizing radiation doses and enhancing the safety and efficacy of vector control strategies.

Comet assay↗
PubMed2025

Biogenic Synthesis and Characterization of Hypecoum pendulum Mediated Silver Nanoparticles: Revealed Outstanding Anticancer and Genotoxic Potentials.

Fabrication of silver nanoparticles by green approach is the most effective and eco-friendly technique in recent technologies. The current study aimed to generate a simple, valid, and justifiable method for biogenic synthesis of silver nanoparticles (HP-AgNPs) using aqueous extract of Hypecoum pendulum L.(HP) and to assess their in&#xa0;vitro anticancer and genotoxic potentials on baby hamster kidney cell (BHK-21) and human blood lymphocytes using 3-(4,5-dimethylthiazol-2-yl-)-2,5-di-phenyltetrazolium bromide (MTT) and alkaline comet assay, respectively. HP-AgNP characterization was done using UV-vis spectrometry, EDX, SEM, XRD, and FTIR techniques. The crystalline nature of HP-AgNPs with a particle size of 36.3&#x2009;nm was assessed using the XRD technique. The surface morphologies with a particle size of 80&#x2009;nm were verified by SEM analysis. UV spectroscopy verified the existence of HP-AgNPs by yielding a sharp peak at 417&#x2009;nm with an absorbance intensity of 1.54. FTIR assessment revealed the existence of different functional moieties that contribute to the HP-AgNPs stabilization and reduction. Similarly, EDX analysis revealed Ag as a principal element (49%). MTT assay showed significant cytotoxicity by Doxorubicin and HP-AgNPs with a smaller IC50 value of 104.21&#x2009;&#xb1;&#x2009;4.33 and 134.91&#x2009;&#xb1;&#x2009;6.33&#x2009;&#x3bc;g/mL correlated to HP extract (229.84&#x2009;&#xb1;&#x2009;4.66&#x2009;&#x3bc;g/mL). The outcomes of the comet assay revealed potential DNA damage in a positive trend with concentration (25-600&#x2009;&#x3bc;g/mL). HP-AgNP-treated lymphocytes showed higher DNA damage as compared to HP extract-treated cells, but less damage as compared to a positive control, H2O2. These outcomes showed that HP-AgNPs have demonstrated promising anticancer and genotoxic action than HP extract due to their size and shape.

Silver↗
PubMed2026

Genotoxic Activity of Cerastes cerastes Viper Venom Using Alkaline Single-Cell Gel Electrophoresis.

In Morocco, Cerastes cerastes snake is responsible for numerous cases of human envenomation, leading to both local and systemic pathophysiological disturbances. This study provides a first preliminary evaluation of cytotoxic and genotoxic effects of its venom on genomic material (Deoxyribonucleotide acid: DNA). The venom protein profile was characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its median lethal dose (LD50) was determined by intraperitoneal injection in mice. Genotoxicity was assessed using the alkaline comet assay (single-cell gel electrophoresis) on peripheral blood cells following in vitro and in vivo venom treatments with sampling performed between 1 and 24 h after exposure. Concurrently, cell death was evaluated using the trypan blue exclusion assay as an indicator of venom-induced cytotoxicity. DNA damage parameters, including percentage of DNA in the head, tail and tail length, were quantified using OpenComet software. The venom exhibited a protein-rich composition and an LD50 of 34.64 &#xb5;g/mouse. The comet assay revealed statistically significant DNA damage compared to the control group. Partial to complete DNA repair was noted after 24 h depending on the administered dose. These findings confirm those obtained with cell death assay. All results indicate that Moroccan C. cerastes venom induces transient DNA damage, potentially associated with oxidative stress mechanisms leading to cytotoxicity. It is primordial to characterize target venom-molecules exhibiting genetic failure in order to find an adequate therapeutic approach.

Cerastes cerastes venom↗
PubMed2026

Genome-scale CRISPR screening uncovers SRSF6 as a target to sensitize hepatocellular carcinoma to radiotherapy.

BACKGROUND & AIMS: Radiotherapy confers clinical benefits to patients with hepatocellular carcinoma (HCC) across all stages, yet its clinical efficacy is limited by radioresistance. This study aimed to identify key regulators of HCC radiosensitivity through genome-wide functional screening. METHODS: A genome-wide CRISPR-Cas9 screen in Huh7 cells identified radiosensitivity regulators, with SRSF6 validated by siRNA knockdown and &#x3b3;-H2AX assessment. Stable shRNA-mediated SRSF6 knockdown was established in Huh7 and HepG2 cells, followed by clonogenic, EdU incorporation, apoptosis, micronucleus, and comet assays. Mechanistically, RNA-seq, Western blotting, mRNA stability assays, RIP-qPCR, and RAD51 overexpression rescue assays were performed. The therapeutic potential of the SRSF6 inhibitor indacaterol was evaluated using MTS assays, HCC xenograft mouse models (BALB/c-nu/nu, n = 28), and HCC patient-derived organoids (PDOs) (n = 3). In addition, SRSF6 expression and its correlation with patient survival were analyzed using data from The Cancer Genome Atlas and a tissue microarray (n = 14 HCC and 14 paired adjacent non-tumorous liver samples). RESULTS: We identified the RNA-binding protein SRSF6 as a driver of HCC radioresistance. SRSF6 depletion enhanced the radiosensitivity of HCC cells (p <0.05-0.0001) by post-transcriptionally destabilizing the mRNAs of critical DNA repair genes (p <0.05-0.0001), thereby impairing radiation-induced DNA damage repair. The radiosensitizing effect of SRSF6 depletion was partially abrogated by ectopic overexpression of the core DNA repair protein RAD51 (p <0.05-0.001). Indacaterol exhibited cytotoxic effects on HCC cells (p <0.05-0.0001) and enhanced the antitumor efficacy of radiation in vivo (p <0.05-0.0001), as further validated across multiple HCC patient-derived organoids (p <0.05-0.0001). CONCLUSIONS: SRSF6 is a key regulator of HCC radioresistance through its post-transcriptional control of DNA repair capacity, and represents a novel therapeutic target to sensitize HCC to radiotherapy. IMPACT AND IMPLICATIONS: In this study, we performed a genome-wide CRISPR-Cas9 knockout library screen to dissect the molecular determinants governing HCC radiosensitivity, and identified RNA-binding protein SRSF6 as a driver of HCC radioresistance. We demonstrate that SRSF6 depletion disrupts the post-transcriptional stability of key DNA repair gene mRNAs and enhances HCC radiosensitivity. These findings are important for radiation oncologists and translational researchers, as they identify SRSF6-dependent RNA regulation as a critical determinant of radiotherapy response in HCC. Practically, we show that the clinically approved bronchodilator indacaterol suppresses SRSF6 function and enhances the antitumor efficacy of radiotherapy, offering a readily repurposable pharmacological strategy to overcome radioresistance. These implications are based on preclinical evidence across multiple models; however, future clinical trials are needed to validate the safety and efficacy of indacaterol-based radiosensitization in patients with HCC.

DNA repair↗
PubMed2025

Candida glabrata replicating within macrophages experiences amino acid deprivation, DNA damage, and chromosome instability.

Macrophages, the central players of innate immunity, control invading microbes by encapsulating them inside the phagosome, a nutrient-poor, reactive oxidant species-rich organelle. Nevertheless, some microbes, including the opportunistic yeast pathogen Candida glabrata, noted for its karyotype diversity, rapid evolution of antifungal drug resistance, and lack of meiosis, can survive and even replicate inside macrophages. However, it is not fully understood how C. glabrata responds to macrophage engulfment, and it is unknown how this presumably DNA-damaging environment influences the pathogen's genome stability. In this study, we used comparative transcriptomics to identify amino acid starvation and DNA damage as conditions eliciting C. glabrata responses most similar to macrophage engulfment. Consistent with this, we found that C. glabrata intra-macrophage survival and replication require master regulator of amino acid biosynthesis GCN4 and functional DNA double-strand break repair. Furthermore, comet assays provided the first direct evidence for increased DNA breaks in intra-macrophage yeast, and pulse-field gel electrophoresis showed that chromosomal alterations occur frequently in macrophage-passaged C. glabrata. Interestingly, these alterations could not be resolved by long read DNA sequencing, suggesting that they involved highly complex repetitive regions. Finally, we identified several point mutations emerging during macrophage passaging and showed that among them, a frameshift in RME1 (repressor of meiosis in Saccharomyces cerevisiae), increased C. glabrata intra-macrophage fitness. Together, these analyses point to amino acid deprivation, reveal elevated DNA breakage and chromosome instability, and raise intriguing questions about the role of meiotic gene orthologs in C. glabrata persisting and replicating within macrophages.

Journal Article↗
PubMed2024

EB-SUN, a new microtubule plus-end tracking protein in Drosophila.

Microtubule (MT) regulation is essential for oocyte development. In Drosophila, MT stability, polarity, abundance, and orientation undergo dynamic changes across developmental stages. In our effort to identify novel microtubule-associated proteins that regulate MTs in the Drosophila ovary, we identified a previously uncharacterized gene, CG18190, which&#xa0;encodes a novel MT end-binding (EB) protein, which we propose to name EB-SUN. We show that EB-SUN colocalizes with EB1 at growing MT plus-ends in Drosophila S2 cells. Tissue-specific and developmental expression profiles from Paralog Explorer reveal that EB-SUN is predominantly expressed in the ovary and early embryos, while EB1 is ubiquitously expressed. Furthermore, as early as oocyte determination, EB-SUN comets are highly concentrated in oocytes during oogenesis. EB-SUN knockout (KO) results in decreased MT density at the onset of mid-oogenesis (stage 7) and delays oocyte growth during late mid-oogenesis (stage 9). Combining EB-SUN KO with EB1 knockdown (KD) in germ cells significantly further reduces MT density at stage 7. Hatching assays of single protein depletion reveal distinct roles for EB-SUN and EB1 in early embryogenesis, likely due to differences in their&#xa0;expression and binding partners. Notably, all eggs from EB-SUN KO/EB1 KD females fail to hatch, suggesting partial redundancy between these proteins.

Animals↗