Oxidative stress markers in prostate cancer patients after HDR brachytherapy combined with external beam radiation.
Assessment of oxidative stress markers was perfomed in prostate cancer (PCa) patients subjected to high-dose brachytherapy (HDR) with external beam radiotherapy (EBRT). Sixty men with PCa were subjected to combined two-fraction treatment with HDR (tot. 20 Gy) and EBRT (46 Gy). Blood samples were taken before treatment, immediately afterwards, after 1.5-3 months, and approx. 2 years. Control group consisted of 30 healthy men. Erythrocyte glutathione peroxidase activity in the patients was lower than in healthy subjects by 34% (P < 0.001), 50% (P < 0.001), 30% (P < 0.05), and 61% (P < 0.001), respectively, at all periods. No significant differences were found by comparing superoxide dismutase and catalase activity in PCa patients with that of the controls. After 2 years of the end of treatment, the activity of studied enzymes demonstrated a decreasing tendency versus before therapy. Blood plasma thiobarbituric acid reactive substances (TBARS) concentration was higher than in the controls at all periods, while erythrocyte TBARS decreased after 2 years to control levels. The results confirm that in the course of PCa, imbalance of oxidant-antioxidant processes occurs. The therapy did not alter the levels of oxidative stress markers, which may prove its applicability. Two years is too short a period to restore the oxidant-antioxidant balance.
Department of Medical Biology, Faculty of Medicine, Nicolaus Copernicus University, Karłowicza 24 Street, 85-092 Bydgoszcz, Poland.
Alina
A
Woźniak
Rafał
R
Masiak
Michał
M
Szpinda
Celestyna
C
Mila-Kierzenkowska
Bartosz
B
Woźniak
Roman
R
Makarewicz
Anna
A
Szpinda
D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001918:Brachytherapy / Q000379:methods*; D002277:Carcinoma / Q000175:diagnosis / Q000532:radiotherapy*; D004912:Erythrocytes / Q000528:radiation effects; D005500:Follow-Up Studies; D005979:Glutathione Peroxidase / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D061766:Proton Therapy / Q000379:methods*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D014408:Biomarkers, Tumor; D017392:Thiobarbituric Acid Reactive Substances; D005979:Glutathione Peroxidase