Lipid peroxidation, free radical production and antioxidant status in breast cancer

Abstract

Reactive oxygen metabolites (ROMs), including superoxide anion (O2*-), hydrogen peroxide (H2O2) and hydroxyl radical (*OH), play an important role in carcinogenesis. There are some primary antioxidants such as superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) which protect against cellular and molecular damage caused by the ROMs. We conducted the present study to determine the rate of O2*- and H2O2 production, and concentration of malondialdehyde (MDA), as an index of lipid peroxidation, along with the SOD, GPx and CAT activities in 54 breast cancer (BC) patients. Forty-two age- and sex-matched patients with minor surgical problems, who had no history of any neoplastic or breast disorders, were taken as controls. The rate of O2*- production was significantly higher (p < 0.001) in BC patients than controls, irrespective of clinical stages and menopausal status. Similarly, H2O2 production was significantly higher in BC patients, especially in stage III and postmenopausal groups, as compared to the respective controls. MDA concentration was also observed significantly elevated in stage II (p < 0.001), stage III (p < 0.01), postmenopausal (p < 0.005), and premenopausal (p < 0.02) group as compared to their corresponding controls. SOD and GPx activities were found significantly raised in all the groups (p < 0.001), except the GPx activity was found a smaller alteration in stage IV (p < 0.02). On the contrary, CAT activity was found significantly depressed in all the study groups. The maximum depression was observed in stage II (-61.8%). Lower CAT activity in our study may be the effect of higher production of ROMs, particularly O2*- and *OH. SOD and GPx, however, were less effected by these higher ROMs production. The results of our study have shown a higher ROMs production and decreased CAT activity, which support the oxidative stress hypothesis in carcinogenesis. The relatively higher SOD and GPx may be due to the response of increased ROMs production in the blood. However, the higher SOD and GPx activities may be inadequate to detoxify high levels of H2O2 into H2O leading to the formation of the most dangerous *OH radical followed by MDA. Therefore, administration of CAT may be helpful in the management of BC patients. However, further elaborate clinical studies are required to evaluate the role of such antioxidant enzymes in BC management.

Plasma and Dietary Carotenoids Are Associated with Reduced Oxidative Stress in Women Previously Treated for Breast Cancer

“…Further, the study populations were markedly different from those in the present study in that a significant percentage of subjects were male, many were smokers, and in the Moller study the mean study subject was >3 decades younger than our participants. The levels of oxidative stress in our study group were not as high as has been suggested for breast cancer patients in other studies (40)(41)(42)(43) and may be related to both the fact that our subjects were recruited, on average, just over two years after breast cancer diagnosis and are considered to be consuming relatively healthy diets since the time of breast cancer diagnosis (37). In fact, the plasma carotenoid concentrations observed in the present study sample are generally higher than those observed in the general population, as reflected in National Health and Nutrition Examination Survey III (44).…”

Moderate alcohol consumption and levels of antioxidant vitamins and isoprostanes in postmenopausal women

“…In a study of 87 women with breast cancer and 29 control women, Li et al (1999) found that cancer patients had significantly higher levels of lipid peroxidation-related DNA adducts in breast tissue samples than controls. Ray et al (2000) evaluated malondialdehyde (MDA) concentration, an index of lipid peroxidation, along with activity of antioxidant enzymes in 54 breast cancer patients and 42 age-matched controls. Their results showed that irrespective of menopausal status, MDA concentration was significantly elevated in patients with stage II or greater breast cancer.…”

“…Levels of F 2 -isoprostanes in body fluids are elevated by conditions that are thought to be associated with free radical-induced oxidative stress, including smoking (Morrow et al, 1995;Reilly et al, 1996), hypercholesterolemia (Davi et al, 1997;Reilly et al, 1998;Palombo et al, 1999), diabetes (Davi et al, 1999), and acute and chronic alcoholic liver disease Meagher et al, 1999). Recent research suggests a role for oxidative stress in breast cancer (Kumar et al, 1991;Thangaraju et al, 1994;Li et al, 1999;Novak & Woodcroft, 2000;Ray et al, 2000).…”

Free radical injury and antioxidant status in patients with benign prostate hyperplasia and prostate cancer

“…Role of free radicals has been proposed in the pathogenesis of many diseases involving different organs such as breast, gastric, colon, multiple myeloma, ovarian and oral cancer (1)(2)(3)(4)(5)(6). Various natural antioxidants available in the cells like glutathione peroxidase (GPx), glutathione S-transferase (GST), superoxide dismutase, catalase, vitamin E and reduced glutathione (GSH) etc.…”