There is no relationship between SOD2 Val-16Ala polymorphism and breast cancer risk or survival

Wang,Chengdi; Liu,Yang; Zhou,Jian; Ye,Lei; Chen,Nan; Zhu,Min; Ji,Yulin

doi:10.3892/mco.2017.1376

There is no relationship between SOD2 Val-16Ala polymorphism and breast cancer risk or survival

Authors:
- Chengdi Wang
- Yang Liu
- Jian Zhou
- Lei Ye
- Nan Chen
- Min Zhu
- Yulin Ji
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Affiliations: Department of Respiratory and Critical Care Medicine, West China Medical School/West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China, Department of Vascular Surgery, West China Medical School/West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China, Department of Thoracic Surgery, West China Medical School/West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
Published online on: August 14, 2017 https://doi.org/10.3892/mco.2017.1376
Pages: 579-590

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Abstract

Breast cancer is the most common diagnosed cancer among females worldwide. Superoxide dismutase 2 (SOD2), an antioxidant enzyme, may break the balance between the oxidant and antioxidant system to induce various diseases. The present study aimed to clarify the association between the SOD2 Val‑16Ala polymorphism and breast cancer risk or survival. Thus, a meta‑analysis of the relevant articles retrieved from PubMed and EMBASE databases was conducted to illuminate the association with odd ratios (ORs) or hazards ratios (HRs). A total of 26 eligible publications (n=38,008) were available in risk analysis and eight publications (n=5,746) in survival analysis. The results demonstrated a marginal association between breast cancer risk and SOD2 polymorphism in Caucasian patients [TT vs. CT + CC: (OR, 0.94; 95% confidence interval (CI), 0.88‑1.00)]. However, no other positive results were observed in risk and survival of breast cancer in the whole study [T vs. C: (OR, 0.99; 95% CI, 0.96‑1.02); CT vs. CC: (OR, 1.00; 95% CI, 0.95‑1.05); TT vs. CC: (OR, 0.98; 95% CI, 0.92‑1.05); TT vs. CT + CC: (OR, 1.00; 95% CI, 0.95‑1.05); CT + TT vs. CC: (OR, 0.99; 95% CI, 0.95‑1.05)]. The present meta‑analysis indicated that there was no significant relationship between SOD2 Val‑16Ala polymorphism and breast cancer risk or survival, although in Caucasian patients, the SOD2 TT genotype may marginally decrease the risk of breast cancer in comparison to the CT + CC genotype.

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