RESUMO
Background: Recently the carcinogenic and toxic effects of some heavy metals such as chromium (Cr), and lead (Pb) through the mechanism of oxidative stress have been reported. Due to the various consequences of chemotherapeutic treatments on body hemostasis, the present study aimed to evaluate the effect of Adriamycin 60 mg/m2 and Cytoxan 600 mg/m2 (AC) chemotherapy on the serum levels of Cr, Pb, and the percent α-diphenyl-ß-picrylhydrazyl (DPPH) inhibition. Methods: This study was performed on 50 patients with breast cancer at two separate sampling times, the first at the initiation of chemotherapy and the last at the end of three courses of the AC chemotherapy treatment. Serum levels of Cr and Pb were measured using atomic absorption spectrophotometry. The percent DPPH inhibition (% I) and also the effect of age and stage of the disease on the mentioned variables were evaluated. Statistical comparison of the obtained results before and after chemotherapy was performed using paired sample t-test. Intra-group evaluation of age and disease stages was done using an independent sample t-test. Results: A significant decrease was observed in the percent DPPH inhibition after 3 courses of chemotherapy (p<0.001). Cr and also Pb were significantly higher in patients with breast cancer after AC chemotherapy (p<0.001). Conclusion: According to the results, AC chemotherapy in patients with breast cancer is associated with higher levels of Cr and Pb, which can eventually lead to worsened oxidative stress status in affected patients. However, it seems that these changes do not necessarily depend on age and the stage of the disease.
RESUMO
BACKGROUND: Chemotherapy for treatment of breast cancer uses some drugs to target and destroy the cancer cells. However, most of antineoplastic treatments are non-specific and the innate cells will be damaged. In this study, the effect of adriamycin/cytoxan (AC) chemotherapy on the status of antioxidant enzymes and Se levels in breast cancer patients was evaluated. METHODS: A prospective study, includes 50 breast cancer patients treated with AC chemotherapy (adriamycin 60 mg/m2, cytoxan 600 mg/m2) from July 2016 until March 2017. First sampling was obtained before chemotherapy and the second, after 3 cycles of the intervention. Antioxidant enzyme activities (catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase) and selenium (Se) levels in serum were measured by spectrophotometry and atomic absorption methods, respectively. Age, BMI, familial history, stage and grade of cancer, tumor site, type of surgery, estrogen, progesterone and HER2 receptors, were recorded from each patient. Paired-t test was employed for comparing the data before and after chemotherapy. Age and disease stages were compared by independent t-test. RESULTS: After 3 courses of chemotherapy, a significant decrease was observed in antioxidant enzymes and also Se (p<0.001). These studied indices were not significant in different age groups (≤48, >48) and stages of disease (early, advanced). CONCLUSION: Our findings show that the AC chemotherapy in the breast cancer patients result in drastic changes in oxidant/antioxidant system of the body, especially reduction of Se levels and antioxidant enzymes activities. However, it seems that these changes are not necessarily dependent on the age and disease stage.
