Value of Urinary 8-hydroxydeoxyguanosine (oh(8)dG) Measurement in Patients with Bladder Cancer

Han, Kwang Hee; Kim, Hun Sik; Kim, Wun Jae

Abstract

PURPOSE: Oxidative DNA damage may play a role in the aging process, carcinogenesis and other degenerative diseases and can be assessed in humans in vivo from the urinary excretion of the DNA repair product, 8-hydroxydeoxyguanosine (oh(8)dG). In order to estimate the urinary oh(8)dG concentration in bladder cancer patients and the effect of smoking on the urinary oh(8)dG excretion, the urinary oh(8)dG levels in bladder cancer patients and control subjects were measured.
MATERIALS AND METHODS
Urine samples were collected from 110 bladder cancer patients and 64 controls. The subjects' smoking history was gathered from a standardized self-completed questionnaire. The urinary oh(8)dG concentration was measured using an oh(8)dG ELISA Kit. The relationship between the urinary oh(8)dG concentration and the bladder cancer stage, grade and smoking history were analyzed.
RESULTS
The urinary oh(8)dG concentration was significantly higher in the control group than in both preoperative and postoperative bladder cancer patients (p=0.049 and p=0.013, respectively). In the bladder cancer patients, the urinary oh(8)dG concentration did not correlate with either the stage or the grade. Regarding the smoking status, the urinary oh(8)dG concentrations of smokers in bladder cancer patients were lower than those of smokers in the control group (p=0.018). In the control group, the urinary oh(8)dG concentrations in smokers were higher than those in nonsmokers (p=0.013). There was no difference of urinary oh(8)dG concentration in bladder cancer patients irrespective of the smoking status.
CONCLUSIONS
The decreased urinary excretion of oh(8)dG in bladder tumor patients suggests that the repair mechanism of oxidative DNA damage, oh(8)dG, might be impaired in bladder cancer patients. Further studies aimed at measuring the DNA concentration of oh(8)dG or its repair activity in bladder tumor tissues are needed to test this possibility.