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BACKGROUND: Cadmium, a metal implicated in environmental toxicity, is linked to tumor growth and cancer. On the other hand, zinc plays an essential function in oxidative stress and can counteract cadmium toxicity and carcinogenicity. This research aims to evaluate the urine and serum values of cadmium and zinc in breast cancer (BC) patients and their association with estrogen (ER) and HER-2 receptors, and redox status. METHODS: Forty BC patients and thirty healthy subjects participated in this study. Cadmium and zinc levels were measured in serum and urine samples by atomic absorption spectrophotometer. Redox status markers were determined by colorimetric methods. RESULTS: The amount of cadmium in the BC patients was substantially greater than in the healthy subjects. Zinc levels were significantly lower in patients with BC compared to controls. Breast cancer patients with ER-positive tumors had significantly higher urinary cadmium concentrations (U-Cd) compared to patients with ER-negative tumors. There was no significant difference between the parameters of redox status and the value of cadmium and zinc between patients with BC in the HER-2 subgroup. Malondialdehyde levels in the serum were substantially greater in BC patients than in healthy subjects. Total thiol level and catalase and superoxide dismutase activity in serum were considerably lower in BC patients than in healthy subjects. CONCLUSIONS: The etiology of BC may be due to a disturbance in redox status and levels of elements. Increasing U-Cd and lowering zinc levels in the serum could be the risk factors for BC.
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Arsenic (As) is an environmental pollutant with carcinogenic effects and breast cancer (BC) is a prevalent malignant tumor in women. The goal of this meta-analysis was to establish a connection between biological sample As levels and the risk of developing BC. Pub Med, Web of Science, Scopus, and Elsevier were used to systematically screen the literature published between 1990 and 2023. The Newcastle-Ottawa scale was also used in assessing the quality of publications. A random-effects model was used to assess the pertinent data that was gleaned from these articles. Using the I2 index the heterogeneity of studies was performed. Egger's test and funnel plots were used to look at publication bias. We identified 16 epidemiologic studies that included 2713 women with BC and 5347 healthy individuals. The results showed that the difference between the case group and the control group was 0.72 [95% confidence interval (CI) 0.30 to 1.14]. According to subgroup analysis, the value for blood was 0.18 [95% CI 0.01 to 0.35], whereas the value for hair was 3.08 [95% CI 0.19 to 5.97]. The present meta-analysis suggested that As levels were significantly higher in BC patients than in controls. This systematic review and meta-analysis provide evidence supporting a positive relationship between arsenic levels in biological media and BC risk. These findings highlight the importance of further research to investigate the mechanisms of this association and explore potential preventive strategies to reduce the adverse effects of arsenic exposure on BC.
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Background: The oxidative balance is a state of equilibrium between oxidants and antioxidants disrupted in various disorders, including BC. This study aimed to assess this equilibrium in breast cancer (BC) patients by looking at the oxidant-to-antioxidant ratio. Methods: This case-control study comprised 40 women patients with breast cancer and 30 age-matched healthy individuals. The oxidation-reduction colorimetric technique was used to determine serum levels of total oxidant status (TOS) and total antioxidant capacity (TAC). The oxidant-to-antioxidant balance was estimated using the TOS- to- TAC ratio (TOS/TAC). Results: The mean TOS in healthy individuals was 8.40±2.06 µmol/L, while in BC patients it was 13.31±2.16 µmol/L (P< 0.001). The mean serum level of TAC was 1.43±0.21 mmol/L in healthy individuals and 1.19±0.15 mmol/L in BC patients (P< 0.001). The mean serum TOS/TAC was 6.01±0.32 in the healthy individuals and 11.42±0.41 in the BC patients (P< 0.0001). There were direct correlations between TAC and estrogen receptor (r=0.339, P=0.038). The TOS/TAC level has a sensitivity of 100% and specificity of 83.33%, distinguishing patients with BC from healthy controls (P< 0.001). A significant trend of increasing risk with rising TOS/TAC levels was also seen [OR=3.62, (95 % CI 1.79, 7.35)]. Conclusions: In breast cancer, the serum TOS to TAC ratio can better diagnose oxidative equilibrium than either component alone.