Oxidative protein damage in cancer patients

In our study, there were 108 patients (70 men, 38 women) who were diagnosed as having gastrointestinal cancer and 35 healthy individuals (25 women, 10 men). Patients were divided into three groups: first group who were diagnosed as having gastric cancer (9 women, 31 men), second group who were diagnosed as having colorectal cancer (13 women, 27 men), third group who were diagnosed as having pancreas, liver and esophagus cancer (16 women, 12 men). In our study patients? serum malondialdehyde (MDA), nitric oxide (NO) and plasma nitrotyrosine (NT) levels compared with healthy individuals?. MDA levels were analyzed spectrophotometrically, NO and NT levels were determined by using kit. Besides, effects of factors such as age, gender, history of family, smoking status, alcohol status, physical exercise, diet habits, dietary fat habit on oxidative stress parameters were statistically evaluated.The levels of MDA, NO and NT were statistically found high in cancer patients compared with the healthy control group (respectively, p=0.000, p=0.000, p=0.012). The correlation of patients? oxidative parameters were observed. It is found that there is a significant correlation between MDA and NO levels (0.285/p=0.003), there is a positive nonsignificant correlation between MDA and NT levels (0.120/p=0.217) and also there is a negative nonsignificant correlation between NO and NT levels (-0.003/p=0.973).When the correlation between oxidative stress parameters of the first group has been observed; there is no statistically significant correlation among MDA, NO and NT levels but a negative nonsignificant correlation has been observed between NO and NT levels (-0.276/p=0.084). When the correlation between oxidative stressparameters of the second group has been observed; there is a statistically significant correlation between NO and NT levels (0.336/p=0.034). When the correlation between oxidative stress parameters of the third group has been observed; there is a statistically significant correlation between MDA and NO levels (0.463/p=0.013), and a negative nonsignificant correlation has been observed between MDA and NT levels (-0.168/p=0.394).