RESUMO
BACKGROUND: Individual susceptibility to endogenous and/or exogenous DNA damage depends on DNA repair efficiency and can be evaluated using the comet assay with bleomycin as genotoxic agent. The aim of the study was to evaluate baseline and bleomycin-induced DNA damage and DNA repair capacity in peripheral blood lymphocytes (PBLs) of endometrial cancer (EC) patients considering a family history of cancer. METHODS: DNA damage was analyzed in PBLs of 45 EC patients compared to a control group of 10 healthy women, using the comet assay. The level of DNA damage was determined by the% tail DNA. RESULTS: The level of baseline DNA damage in PBLs of EC patients was significantly higher (% DNA in tail 9.31 ± 15.32) than in healthy women (% DNA in tail 3.41 ± 4.71) (P <0.01). PBLs of EC patients repaired less bleomycin-induced DNA damage (removed% DNA in tail 63.94 ± 20.92) than PBLs of healthy individuals (removed% DNA in tail 80.24 ± 3.03) (P <0.001). Efficiency of DNA repair in PBLs of EC patients depended on the family history of cancer. The amount of restored damaged DNA was significantly lower (removed% DNA in tail 36.24 ± 14.05%) in EC patients with a family history of cancer compared to patients with sporadic EC (removed% DNA in tail 64.91 ± 19.36%) (P <0.004). CONCLUSIONS: Lymphocytes of EC patients are characterized by an increased basal level of DNA damage as well as deficiency in DNA repair. DNA repair is less efficient in PBLs of EC patients with a family history of cancer compared to patients with sporadic cancer.
Assuntos
Dano ao DNA , Reparo do DNA , Neoplasias do Endométrio/genética , Linfócitos/metabolismo , Adulto , Idoso , Bleomicina/farmacologia , Estudos de Casos e Controles , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Distúrbios no Reparo do DNA , Feminino , Humanos , Linfócitos/efeitos dos fármacos , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
PURPOSE: Our study was designed to assess the effects of low intensity radiation of a GSM (Global System for Mobile communication) 900 MHz cellular phone on early embryogenesis in dependence on the duration of exposure. MATERIALS AND METHODS: Embryos of Japanese Quails were exposed in ovo to GSM 900 MHz cellular phone radiation during initial 38 h of brooding or alternatively during 158 h (120 h before brooding plus initial 38 h of brooding) discontinuously with 48 sec ON (average power density 0.25 µW/cm(2), specific absorption rate 3 µW/kg) followed by 12 sec OFF intervals. A number of differentiated somites were assessed microscopically. Possible DNA damage evoked by irradiation was assessed by an alkaline comet assay. RESULTS: Exposure to radiation from a GSM 900 MHz cellular phone led to a significantly altered number of differentiated somites. In embryos irradiated during 38 h the number of differentiated somites increased (p < 0.001), while in embryos irradiated during 158 h this number decreased (p < 0.05). The lower duration of exposure led to a significant (p < 0.001) decrease in a level of DNA strand breaks in cells of 38-h embryos, while the higher duration of exposure resulted in a significant (p < 0.001) increase in DNA damage as compared to the control. CONCLUSION: Effects of GSM 900 MHz cellular phone radiation on early embryogenesis can be either stimulating or deleterious depending on the duration of exposure.