RESUMO
A hospital-based unmatched case-control study was performed in order to determine the relation of DNA single (ssb) and double (dsb) strand breaks in women with and without cervical neoplasia. Cervical epithelial cells of 30 women: 10 with low grade squamous intraepithelial lesions (LG-SIL), 10 with high-grade SIL (HG-SIL), and 10 without cervical lesions were evaluated using alkaline and neutral comet assays. A significant increase in global DNA damage (ssb + dsb) and dsb was observed in patients with HG-SIL (48.90 ± 12.87 and 23.50 ± 13.91), patients with LG-SIL (33.60 ± 14.96 and 11.20 ± 5.71), and controls (21.70 ± 11.87 and 5.30 ± 5.38; resp.). Pearson correlation coefficient reveled a strong relation between the levels ssb and dsb (r(2) = 0.99, P = 0.03, and r(2) = 0.94, P = 0.16, resp.) and progression of neoplasia. The increase of dsb damage in patients with HG-SIL was confirmed by DNA breakage detection-FISH (DBD-FISH) on neutral comets. Our results argue in favor of a real genomic instability in women with cervical neoplasia, which was strengthened by our finding of a higher proportion of DNA dsb.
Assuntos
Ensaio Cometa/métodos , Quebras de DNA de Cadeia Dupla , Quebras de DNA de Cadeia Simples , DNA de Neoplasias/genética , Predisposição Genética para Doença/genética , Neoplasias do Colo do Útero/genética , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: To investigate the association between the progressive stage of cervical dysplasia and DNA damage by comet assay. STUDY DESIGN: A hospital-based, unmatched, case-control study was performed. DNA damage levels (none, low, medium and high) in the cervical epithelial cells of 31 women (10 with low grade squamous intraepithelial lesions [LSIL], 10 with high grade [HSIL] and 11 with no cervical lesion) were evaluated using the comet assay. RESULTS: A significant increase in medium DNA damage was observed in women with HSIL (17 +/- 8.9) relative to that in the control women (9 +/- 6.1). A significant increase in high DNA damage was also observed in women with LSIL (23 +/- 15.4) or HSIL (32 +/- 13.1) relative to that in the control women (12 +/- 7.9). CONCLUSION: These findings confirm that the grade of a cervical lesion correlates with the degree of genomic instability.