8-Hydroxy-2 '-deoxyguanosine in cervical cells: correlation with grade of dysplasia and human papillomavirus infection

In this study, the 8-hydroxy-2'-deoxyguanosine (8-OHdG) level was assessed in human cervical cells by an immunoperoxidase method and was related to th e presence of human papillomavirus (HPV) infection and precancerous lesions . After optimizing the immunohistochemical method of detecting oxidative DN A damage in whole cells, we have used this technique to estimate the oxidat ive damage in cervical cells collected during a routine PAP test. The analy sis of variance (ANOVA) of the data from human samples showed significant d ifferences in the 8-OHdG content among normal, low-grade and high-grade squ amous intraepithelial lesion (SIL, HGSIL and LGSIL, respectively; P < 0.001 ). In the comparison of the three groups, statistically significant differe nces were detected between normal SIL and HGSIL (P < 0.001) and between LGS IL and HGSIL (P = 0.003), whereas no statistically significant difference w as found between normal SIL and LGSIL (P = 0.1). Grouping observations by H PV status, no significant difference was detected in 8-OHdG levels between HPV+ and HPV- subjects (P = 0.8). The polytomous and proportional odds mode ls, extensions of the logistic regression analysis, showed that the effect of 8-OHdG levels in rising the risk of dysplasia was roughly constant throu gh SIL grades. In conclusion, the immunoperoxidase method, applied to singl e human cervical cells, provides clear evidence that significant difference s exist in 8-OHdG content between normal and dysplastic cells and that oxid ative DNA damage might play an important role in cervical carcinogenesis.