Evaluation of the role of oxidative DNA damage marker 8-hydroxy-2-deoxyguanosine in patients with breast cancer

Background: DNA damage by oxygen free radicals, frequently leads to initiation and progression of human cancer related mutations. Among all the purine and pyrimidine bases, guanine base tends to be the more oxidized one. In previous studies, 8-hydroxy-2-deoxyguanosine (8-OHdG) is the most commonly measured marker to indicate the degree of endogenous oxidative DNA damage. 8-OHdG can be measured at high sensitivity, and its levels are correlated with oxidative stress and cancer incidence in the target tissues. Objective: Our purpose was to assess the possible role of serum 8-hydroxy-2-deoxyguanosine in patients with breast cancer. Subjects and Methods: Blood samples were collected from 40 females newly diagnosed with breast cancer and 30 healthy females as control group. The level of serum 8-OHdG was measured by enzyme linked immunossorbent assay (ELISA). Results: There were highly significant differences (P<0.001) in the mean serum levels of 8-OHdG in breast cancer patients in comparison to controls. Serum 8-OHdG had high diagnostic performance in breast cancer using ROC curve analysis and associated with the risk of breast cancer using logistic regression analysis. Conclusions: Serum 8-OHdG was highly elevated in breast cancer patients in comparison to controls and it may be a carcinogenic factor in breast cancer. Serum 8-OHdG has high diagnostic performance in breast cancer and associated with breast cancer risk. Serum 8-OHdG has no impact on survival outcome in breast cancer patients.