Polymorphisms in the telomerase reverse transcriptase promoter are associated with risk of breast cancer: A meta-analysis

Aims: Recently, the relationship between telomerase reverse transcriptase (TERT) polymorphisms and breast cancer risk has been investigated in several publications. However, the results were inconclusive. In this study, we examined the association between TERT polymorphisms and breast cancer risk by meta-analysis. Materials and Methods: The PubMed, Cochrane Library, and EMBASE databases were searched independently by two investigators to retrieve relevant studies published to March 21, 2015. The strength of the association was calculated with the odds ratio (OR) and 95% confidence interval (CI). All statistical tests were used by the RevMan 5.1 software (Nordic Cochrane Center, Copenhagen, Denmark). Results: We observed a statistically significant association between rs2736109 polymorphism and breast cancer risk (OR = 1.13; 95% CI: 1.00u1.28; P = 0.04). In addition, rs2736109 polymorphism was associated with breast cancer risk in Caucasian population (OR = 1.18; 95% CI: 1.00u1.38; P = 0.04). We also found rs2853669 and rs2736098 polymorphisms were significantly associated with breast cancer risk (OR = 0.76; 95% CI: 0.63u0.90; P = 0.002 and OR = 0.79; 95% CI: 0.72u0.87; P 0.00001), respectively. Furthermore, rs10069690 polymorphism was showed to be associated with breast cancer risk (OR = 1.16; 95% CI: 1.11u1.22; P 0.00001). In the subgroup analysis, this polymorphism might be associated with estrogen receptor-negative breast cancer risk (OR = 1.16; 95% CI: 1.12u1.21; P 0.00001) and breast cancer risk in Caucasian population (OR = 1.18; 95% CI: 1.14u1.23; P 0.00001). One single nucleotide polymorphism, rs2735940, was not significantly associated with breast cancer risk (OR = 0.85; 95% CI: 0.66u1.11; P = 0.24). Conclusion: This meta-analysis suggested that TERT rs2736109, rs2853669, rs2736098, and rs10069690 polymorphisms were associated with increased risk of developing breast cancer.