In vivo exposure to benzo(a)pyrene induces significant DNA damage in mouse oocytes and cumulus cells.

STUDY QUESTION: Does in vivo exposure to benzo(a)pyrene (BaP) induce DNA damage in oocytes and cumulus cells (CCs) in mice? SUMMARY ANSWER: Significant increases in DNA strand breaks in oocytes and CCs and in BaP-induced DNA adducts in CCs were detected in exposed mice compared with controls. WHAT IS KNOWN ALREADY: BaP has well-known mutagenic and carcinogenic effects on somatic cells, and is also registered as potential reproductive toxicant by several environmental protection agencies. It has been shown to cause a significant increase in DNA adducts in ovarian tissues; however, to our knowledge, the genotoxic effects of BaP on oocytes and CCs have not been studied to date. STUDY DESIGN, SIZE, DURATION: Female CD1 mice were exposed to BaP via the oral administration of a single dose of 13 mg/kg body weight (bw); matched controls were exposed to the vehicle only (soya oil). A total of 15 groups of 6 mice (exposed or controls) were sacrificed 2, 4, 6, 15 or 22 days after BaP exposure, and after collection of oviducts, the oocyte-CC complexes (COC) were released. PARTICIPANTS/MATERIALS, SETTING, METHODS: The alkaline comet assay was used to quantify the DNA breaks in oocytes and CCs; DNA damage was expressed as the Olive Tail Moment (OTM). Immunofluorescent staining was used to quantify BaP-induced DNA adducts in CCs. Fluorescence was expressed as the average grey value (AGVA; arbitrary units). The differences between the exposed and control groups were assessed using analysis of variance (ANOVA) and the non-parametric Mann-Whitney test. MAIN RESULTS AND THE ROLE OF CHANCE: Higher levels of DNA damage were observed in the oocytes and CCs of BaP-exposed mice than in those of vehicle controls. Significant increases in OTM (mean ± SE) were detected in (i) oocytes from females exposed for 4 (10.5 ± 0.9 versus 3.1 ± 0.4, P < 0.0001) or 6 days before collection (15.6 ± 2.0 versus 3.6 ± 0.9, P < 0.0001) and (ii) CCs from females exposed 2 (6.4 ± 0.6 versus 2.1 ± 0.2, P < 0.0001), 4 (7.8 ± 0.4 versus 2.4 ± 0.1, P < 0.0001) or 6 days before collection (7.3 ± 0.3 versus 3.2 ± 0.5, P < 0.0001) compared with controls. A significant increase in benzo(a)pyrene-7,8-9,10 diol epoxide (BPDE)-DNA adducts and higher AGVA (mean ± SE) scores were observed in CCs from females exposed 2 (6.1 ± 0.3 versus 3.6 ± 0.5, P < 0.0001), 4 (7.5 ± 0.1 versus 3.4 ± 0.1, P < 0.0001) or 6 days before collection (11.6 ± 0.4 versus 3.7 ± 0.1, P < 0.0001) compared with control mice. LIMITATIONS, REASONS FOR CAUTION: Mice were given one treatment via the oral route because this dose and mode of administration have been shown to induce detectable BPDE-DNA adduct levels in mouse organs and sperm cells. Additional data are needed to assess DNA damage in oocytes and CCs after chronic exposure to BaP in vivo. WIDER IMPLICATIONS OF THE FINDINGS: To our knowledge, this is the first study examining the in vivo genotoxicity of BaP in oocytes and CCs. We observed significant DNA damage in the oocytes and CCs of mice after acute BaP exposure. BPDE-DNA adducts result directly from BaP metabolism while DNA breaks could result mainly from BPDE-DNA adduct excision and repair and/or through direct genotoxicity from increased reactive oxygen species. These results add new and important insights regarding the recently suggested toxicity of chronic BaP exposure in the ovary. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a grant (93-CPQ 2012-05) from the DIRRECTE, Provence Alpes Côte d'Azur, France. None of the authors have any conflict of interest to declare.

[How are excisional therapies for CIN performed in France? A national audit]. / Comment les traitements d'exérèse des CIN sont-ils réalisés en France ? Une enquête nationale.

OBJECTIVES: Evaluate how excisional therapies are performed in France and if colposcopy is used for the guidance of excision. MATERIALS AND METHODS: A national survey was performed among French gynecologists using an anonymous online questionnaire. RESULTS: A total of 555 (14.9%) gynecologists participated to the survey, only answers from the 396 (71.3%) who answered practicing excisional therapies for CIN were considered. LLETZ was the most common excisional technique employed (84.9%). Among respondents, 275 (69.3%) answered not using colposcopy at the time of excision, 67 (16.9%) answered performing excisions under naked eye vision immediately after they had performed a colposcopic examination and 52 (13.8%) under direct colposcopic vision. Although initial colposcopic training did not influence the probability to use colposcopy at the time of excision, the probability of performing excisions immediately after a colposcopic examination or under direct colposcopic vision was significantly increased by the monthly practice of 30 or more colposcopic examinations (AOR: 3.34; 95%CI: 1.54-7.26 and AOR: 2.16; 95%CI: 1.08-4.34, respectively) and by the monthly practice of 5 or more excisional therapies (AOR: 3.06; 95%CI: 1.42-6.56 and AOR: 3.03; 95%: 1.54-5.96, respectively). CONCLUSION: Only a minority of French gynecologists uses colposcopy for the guidance of excisional therapies for CIN. Such practice seems to be influenced by the number of colposcopic examinations and of excisions they perform in a month.

[Evaluation of practices of excisional therapies for CIN: An audit of surgery rooms from Marseilles' area]. / Évaluation des modalités de réalisation des conisations pour le traitement des CIN : enquête auprès des blocs opératoires de la région PACA.

OBJECTIVE: To evaluate what is the proportion of surgery rooms from Marseilles' area that do perform excisional therapies for CIN without any use of colposcopic guidance. MATERIALS AND METHODS: From November 2012 to January 2013, a survey was conducted among all surgery rooms from Marseilles' area practicing excisional therapies for CIN. In addition, answers from gynecologists from Marseilles' area who participated to a national survey that evaluated practices of excisional therapies in France were specifically analyzed. RESULTS: Among the 55 surgery rooms from Marseilles' area practicing excisional therapies, 52 (94.1%) participated to the current survey. A colposcope was available in only 19 (36.5%) surgery rooms and was systematically used for the guidance of excisional therapies in only 4 (21%) of these surgery rooms. Finally, 36 (69.2%) surgery rooms answered performing excisional therapies without any use of colposcopic guidance. Colposcopy was occasionally and systematically used in 12 (23.1%) and 4 (7.7%) surgery rooms, respectively. Among the 116 gynecologists from Marseilles' area who answered to the national survey, 88 (75.9%) answered not using colposcopy when performing excision for CIN. Only 6% answered performing excision systematically under direct colposcopic vision and 18.1% occasionally. CONCLUSION: No colposcopic guidance is used when performing excision for CIN in the majority of surgery rooms from Marseilles' area.