Biomarker evidence of DNA oxidation in lung cancer patients: Association of urinary 8-hydroxy-2'-deoxyguanosine excretion with radiotherapy, chemotherapy, and response to treatment

Ratios of urinary 8-hydroxy-2'-deoxyguanosine to urinary creatinine (8-OHdG/creatinine) have been considered as a good biological indicator of DNA oxidation, Urinary 8-OHdG/creatinine levels of lung cancer patients were evaluated by enzyme-linked immunosorbent assay using a monoclonal antibody N45.1 during radiotherapy and chemotherapy, An increase in urinary 8-OHdG/creatinine was found in non-small-cell carcinoma (non-SCC) patients during the course of radiotherapy, SCC patients showed higher levels of urinary 8-OHdG/creatinine than the controls. Furthermore, SCC patients with complete or partial response to the chemotherapy showed a significant decrease in urinary 8-OHdG/creatinine while patients with no change or progressive disease showed an increase. (C) 1997 Federation of European Biochemical Societies.