SERUM VITAMIN E AND MALONDIALDEHYDE (MDA) LEVELS IN CASES WITH HEAD AND NECK CANCER

Yesim ÖZKAN*, Sertaç SOLAK**, Bolkan SIMSEK*, Meral TORUN*°

* Gazi University, Faculty of Pharmacy, Department of Biochemistry, Hipodrom, Ankara, TURKEY.
** SSK Ankara Hospital, Department of Clinical Biochemistry, Aydinlikevler, Ankara, TURKEY.
°Corresponding Author

Summary:
Lipid peroxidation is a complex chain reaction and a very important process in free radical pathology. Malondialdehyde (MDA) is one of the aldehydic end products of this process. These end products can cause DNA damage, and lipid peroxidation-induced damage to DNA may be involved in carcinogenesis.Vitamin E is the most effective lipid soluble antioxidant, and vitamin E protect critical cellular structures against damage from oxygen free radicals and reactive products of cancer initiation and promotion. In this study, malondialdehyde levels as an index of lipid peroxidation, antioxidant vitamin E, cholesterol and triglyceride levels were determined in sera obtained from 54 patients newly diagnosed with head and neck cancer(Larynx carcinoma, n=35; Others, n=19) and healthy subjects (n=54). The effects of age, sex, quetelet index (kg/cm2) and stages of cancer upon these parameters were evaluated. In addation, any possible correlation between MDA and vitamin E levels was investigated. MDA levels were measured by the modified Yoshioka's TBA method and vitamin E levels were measured by Martinek's method. MDA levels were significantly higher in the patient group(9.09?6.03 ?mol/L) when compared with control group (3.87?0.72 ?mol/L) (p?0.001). Vitamin E levels of cases (0.36?0.15 mg/dL) were lower than those of controls (0.81?0.07 mg/dL) , (p?0.001). In our study cholesterol and triglyceride levels of cases were similar to controls. There were no statistically significant differences between cases and controls in terms of these parameters. Except for age and quetelet index, no statistically significant differences were found among stages and the subgroups of sex, in terms of MDA and Vit.E levels. In this study, according to alcohol intake and cigarette smoking, MDA and vitamin E levels could not be evaluated because of the fact that all the cases were ex-smokers and also were not drinking alcohol. There was no correlation between MDA levels and vitamin E levels in both cases and controls. The results of this study indicate that there is an increase in lipid peroxidation and a decrease in vitamin E levels in carcinogenesis.

Key words:
Head and Neck Cancer, Lipid Peroxidation, Malondialdehyde (MDA), Antioxidant, Vitamin E.