Serum antioxidant and cholesterol levels in patients with different types of cancer

Serum antioxidant (urate, alpha -tocopherol) activity and cholesterol concentration in 142 patients of Indian and rab (Kuwaitis and other Arabs) origin with different types of cancer (breast, colon, stomach, thyroid, oral, rectal, pancreatic, and renal) were compared to 100 age- and sex-matched control subjects. Values were expressed as medians (interquartile range). Urate concentration was significantly decreased in male patients compared to male controls (P < 0.0001) and in female patients and female breast cancer cases compared to female controls; P< 0.0001 and P= 0.001, respectively. alpha -Tocopherol concentration decreased significantly in total cancer, stomach, colon, rectal, and breast cancer cases than the controls; P < 0.0001, P < 0.0001, P < 0.0001, P = 0.012, and P = 0.022, respectively. Cholesterol concentration decreased significantly in stomach, oral, colon, and total cancer cases compared to the controls; P < 0.0001, P < 0.0001, P = 0.002, and P = 0.012, respectively. Among controls, females had significantly (P < 0.0001) lower concentrations of a-tocopherol than males. Among patients, cholesterol, urate, and alpha -tocopherol concentrations decreased significantly in smokers than in nonsmokers; P < 0.0001, P = 0.004, and P = 0.047, respectively. Generally, changes in <alpha>-tocopherol/cholesterol ratios mimicked changes in alpha -tocopherol concentration. Concentrations of all parameters decreased significantly in male patients compared to male controls. Age was positively associated with all three analytes with respect to the controls. alpha -Tocopherol correlated with cholesterol in cancer patients (r = 0.367; P < 0.0001) and with urate in the controls (r = 0.342; P < 0.0001). The data suggest cancer-related diminished synthesis of cholesterol and, generally, a greater antioxidant burden for alpha -tocopherol than urate in cancer-generated oxidative stress. The increased incidence of pancreatic cancer in Kuwaitis warrants further study. J. Clin. Lab. Anal. 15:324-330, 2001. (C) 2001 Wiley-Liss, Inc.