The
oxidant/
antioxidant balance has been implicated in the pathophysiology of
prostate cancer. We investigated oxidative damage and
antioxidant status in high-risk
prostate cancer subjects.
Reduced glutathione (GSH) levels were measured in erythrocytes,
8-hydroxydeoxyguanosine (8-OHdG) in leukocytes and plasma levels of
catalase (CAT),
glutathione peroxidase (GSH-Px),
glutathione reductase (GSH-R),
glutathione S-transferase (GST),
superoxide dismutase (SOD), and
lipid peroxide products were measured in high-risk and age-matched healthy subjects. Serum PSA levels were significantly higher (p < 0.0001) in high-risk subjects, whereas GST (p < 0.0001) and GSH (p < 0.002) were higher in healthy controls. Levels of 8-OHdG, an oxidized
nucleoside of
DNA, were significantly increased (p < 0.0001) in high-risk subjects. No marked difference in the levels of CAT (p = 0.237), GSH-Px (p = 0.74), GSH-R (p = 0.344), SOD (p = 0.109), and
lipid peroxide products (p = 0129) were observed between two groups. Pearson's correlation between GST and PSA (r = -0.69 (p < 0.0001)), GST and 8-OHdG (r = -0.62 (p < 0.0004)), GSH and 8-OHdG (r= -0.39 (p = 0.038)), and CAT and GSH-Px (r= -0.33 (p = 0.04)) were found to be negatively correlated, whereas 8-OHdG and PSA were positively associated (r= 0.57 (p < 0.002). These results indicate a significant role of oxidative damage in prostate
carcinogenesis, particularly during the early stages of development. In conclusion, our data support the importance of
antioxidant defense as a valuable diagnostic and/or prognostic marker in
prostate cancer.