Back to Journals » OncoTargets and Therapy » Volume 8

CAG repeat polymorphisms in the androgen receptor and breast cancer risk in women: a meta-analysis of 17 studies

Authors Mao Q, Qiu M, Dong G, Xia W, Zhang S, Xu Y, Wang J, Rong Y, Xu L, Jiang F

Received 20 March 2015

Accepted for publication 18 June 2015

Published 13 August 2015 Volume 2015:8 Pages 2111—2120


Checked for plagiarism Yes

Review by Single-blind

Peer reviewer comments 4

Editor who approved publication: Dr Faris Farassati

Qixing Mao,1–3,* Mantang Qiu,1–3,* Gaochao Dong,3 Wenjie Xia,1–3 Shuai Zhang,1,3 Youtao Xu,1,3 Jie Wang,3 Yin Rong,1,3 Lin Xu,1,3 Feng Jiang1,3

1Department of Thoracic Surgery, Nanjing Medical University Affiliated Cancer Institute of Jiangsu Province, 2Fourth Clinical College of Nanjing Medical University, 3Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing, People’s Republic of China

*These authors contributed equally to this work

Abstract: The association between polymorphic CAG repeats in the androgen receptor gene in women and breast cancer susceptibility has been studied extensively. However, the conclusions regarding this relationship remain conflicting. The purpose of this meta-analysis was to identify whether androgen receptor CAG repeat lengths were related to breast cancer susceptibility. The MEDLINE, PubMed, and EMBASE databases were searched through to December 2014 to identify eligible studies. Data and study quality were rigorously assessed by two investigators according to the Newcastle-Ottawa Quality Assessment Scale. The publication bias was assessed by the Begg’s test. Seventeen eligible studies were included in this meta-analysis. The overall analysis suggested no association between CAG polymorphisms and breast cancer risk (odds ratio [OR] 1.031, 95% confidence interval [CI] 0.855–1.245). However, in the subgroup analysis, we observed that long CAG repeats significantly increased the risk of breast cancer in the Caucasian population (OR 1.447, 95% CI 1.089–1.992). Additionally, the risk was significantly increased in Caucasian women carrying two alleles with CAG repeats ≥22 units compared with those with two shorter alleles (OR 1.315, 95% CI 1.014–1.707). These findings suggest that long CAG repeats increase the risk of breast cancer in Caucasian women. However, larger scale case-control studies are needed to validate our results.

Keywords: androgen, CAG repeat polymorphism, women, breast cancer, risk, meta-analysis

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]