Activities of erythrocyte antioxidant enzymes in cancer patients.
We measured the activities of erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPX) before therapy in 97 patients with cancer in various sites (gastrointestinal tract (GIT) (n=40), breast (n=30), and others (n=27)), and in 60 matched controls to assess antioxidant enzyme protection. Hemolysate hemoglobin (Hb) was measured spectrophotometrically. The activity of SOD (U/g Hb) was significantly lower in all sites (when all the cancer sites were considered as a group), GIT, breast, and other sites compared to the controls (P<0.0001, P<0.0001, P<0.0001 and P<0.0001, respectively). The activity of GPX (U/g Hb) was significantly decreased in all sites, GIT, and breast cancer sites than in the controls (P=0.024, P=0.033, and P=0.043, respectively). Age showed a weak negative correlation with enzyme activities in controls and patients. There was no significant association between SOD and GPX activities in either the controls or the patients. These results suggest that there may be a greater antioxidant burden for SOD than GPX in cancer, and that a weak association exists between the activities of the two enzymes in antioxidant protection.
Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Kuwait University, Sulaibikhat, Kuwait. clifford@hsc.kuniv.edu.kw
Clifford
C
Abiaka
Farida
F
Al-Awadi
Hilal
H
Al-Sayer
Sima
S
Gulshan
Abdulla
A
Behbehani
Medhat
M
Farghally
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000201:enzymology; D016022:Case-Control Studies; D002648:Child; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000201:enzymology*; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D013482:Superoxide Dismutase / Q000378:metabolism*
D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase