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Pesticides widely used in agriculture and other applications have been linked to cancer and other diseases through several potential mechanisms. The goals of this study were to assess DNA damage in lymphocytes by the cytokinesis-block micronucleus assay (CBMN), and to measure circulating cell free DNA (ccf-DNA) in the blood of pesticide-exposed greenhouse workers and matched controls living in the same area. CBMN was applied to peripheral blood lymphocyte samples taken at different times (spring and autumn) for each individual. We measured plasma ccf-DNA levels using a Qubit fluorometer. The results indicated that the MNL, BNMN, and NBUDs frequencies of pesticide-exposed individuals were significantly higher than non-exposed individuals. Apart from MNL, BNMN and CBPI, a season-related effect was found for the NPB and NBUD frequencies. With MNL and BNMN as the dependent variables, multiple regression analysis showed that age and gender affected MN formation. The ccf-DNA level in the pesticide-exposed group was significantly higher than the control group. There was no seasonal variation regarding the free DNA amount. Ccf-DNA in males was found to be higher than females. The MNL, BNMN, NPB, and CBPI did not correlate with the ccf-DNA amount. It can be concluded that pesticide exposure can modulate DNA integrity via different mechanisms. Also, elevated levels of ccf-DNA could be recommended as a biomarker of pesticide exposure. Environ. Mol. Mutagen. 59:161-169, 2018. © 2017 Wiley Periodicals, Inc.

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Nasopharyngeal carcinoma (NPC) has distinct epidemiological and histological features among head and neck cancers. Clinical signs in patients with NPC change according to the tumor size and the status of lymph node metastases. Tumor can expand anteriorly to nasal cavity, pterygoid fossa or maxillary sinus, laterally to parapharyngeal space and infratemporal fossa, or posterosuperiorly to cranial base, clivus and intracranial structures. Radiotherapy is the primary treatment in NPC. In tertiary centers, intensity modulated radiotherapy (IMRT) is the preferred radiotherapy module. Concurrent chemoradiotherapy is the standard treatment of locally advanced NPC. Standard regimen includes radiation to 70 Gy to the gross tumor in daily fractions of 2 Gy and additional chemotherapy which includes 100 mg/m 2 of cisplatin every 3 weeks or 30-40 mg/m 2 once a week.In this article, updated staging in American Joint Committe on Cancer (AJCC) 8 th edition guidelines, diagnostic methods and treatment modalities in NPC are reviewed and presented in the light of current literature.

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Antidepressants are drugs used for the treatment of many psychiatric conditions including depression. There are findings suggesting that these drugs might have genotoxic, carcinogenic, and/or mutagenic effects. Therefore, the present in vitro study is intended to investigate potential genotoxic and cytotoxic effects of the antidepressants escitalopram (selective serotonin reuptake inhibitor) and doxepin (Tricyclic antidepressant) on human peripheral lymphocytes cytokinesis-block micronucleus (CBMN), sister chromatid exchange (SCE), and single cell gel electrophoresis (alkaline comet assay) were used for the purpose of the study. In the study, four different concentrations of both drugs (1, 2.5, 5, and 10 µg/mL) were administered to human peripheral lymphocytes for 24 h. The tested concentrations of both drugs were found to exhibit no cytotoxic and mitotic inhibitory effects. SCE increase caused by 5 and 10 µg/mL of escitalopram was found statistically significant, while no statistically significant increase was observed in DNA damage and micronucleus (MN) formation. Moreover, the increase caused by doxepin in MN formation was not found statistically significant. Besides, 10 µg/mL of doxepin was demonstrated to significantly increase arbitrary unit and SCE formation. These findings suggest that the investigated concentrations of escitalopram and doxepin were non-cytotoxic but potentially genotoxic at higher concentrations.

Tetrachlorvinphos is an organophosphate that is classified as a carcinogen in humans by several authorities. Due to very limited data regarding the genotoxic potential, we aimed to comprehensively investigate in vitro genotoxic potential of tetrachlorvinphos. We performed our study by applying the cytokinesis-block micronucleus cytome and sister chromatid exchange (SCE) assays to human peripheral blood lymphocytes. We evaluated micronucleus (MN) and SCE frequencies and cytokinesis-block proliferation index in both exposed and non-exposed lymphocytes. We also calculated the chromosomal instability level in response to exposure by combining the results of MN and SCE. We found that MN frequency did not increase with exposure to tetrachlorvinphos (0–50 µg/ml). In contrast, we observed that SCE frequencies significantly increased with exposure to ≥5 µg/ml tetrachlorvinphos. Furthermore, exposure to tetrachlorvinphos at concentrations of 50 µg/ml induced a significant increase in chromosomal instability level ( p < 0.05). Cytokinesis-block proliferation index level did not significantly decrease in response to tetrachlorvinphos exposure. Our findings reveal that tetrachlorvinphos resulted in different DNA damages that were measured by two assays. Furthermore, our findings suggested that exposure to tetrachlorvinphos increased chromosomal instability that is a hallmark of many malignancies. We conclude that although tetrachlorvinphos does not significantly increase the MN level, the significant increase of both SCE and CIN frequencies indicates the genotoxic potential of tetrachlorvinphos in human peripheral lymphocytes. Additionally, tetrachlorvinphos is not cytotoxic in the range of tested concentrations.

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