Abstract
BackgroundThe role of progesterone receptor (PGR) gene polymorphisms in breast cancer is still controversial. Here, we performed a meta-analysis to determine whether the Alu insertion is associated with an increased risk of breast cancer and, further, whether the Alu insertion contributes to the development of breast cancer.MethodsUsing database searches, we selected 10 controlled case studies that met a rigorous set of inclusion criteria; these studies included 2106 cases and 1660 controls. We generated odds ratios and 95% confidence intervals in order to determine the strength of the relationship between the Alu insertion and breast cancer incidence. We also performed additional subgroup analyses and sensitivity analyses to further clarify the relationship.ResultsUsing a random effects model, we concluded that the Alu insertion was not associated with the risk of breast cancer under the dominant genetic model; the pooled OR was 1.025 (95% CI = 0.526–1.994, p = 0.943). When a subgroup analysis was performed according to ethnicity, we found that the Alu insertion was associated with breast cancer incidence in Indians and Indo-European mixed racial groups, but the association disappeared for patients of Caucasian or Latino decent.ConclusionsOur meta-analysis showed that the Alu-insertion progesterone receptor gene polymorphism was not associated with breast cancer. These results provide further information regarding the association between the Alu insertion in the PGR gene and the incidence of breast cancer.
Highlights
The role of progesterone receptor (PGR) gene polymorphisms in breast cancer is still controversial
We found no association between the Alu insertion and the risk of breast cancer in a subgroup analysis by source of controls
Our meta-analysis included 10 studies, comprised of 2106 cases and 1660 controls, that investigated the association between PGR gene polymorphism and the occurrence of breast cancer
Summary
The role of progesterone receptor (PGR) gene polymorphisms in breast cancer is still controversial. A multitude of factors have been postulated to influence the development of breast cancer including age, ethnicity, early or delayed menarche, use of oral contraceptives, breastfeeding, and age at menopause as well as a number of genetic factors [4, 5]. The human progesterone receptor, encoded by the PGR gene, is a member of the steroid receptor superfamily. Membrane PGR have been shown to mediate most non-classical progesterone actions; as such, membrane PGRs may be useful as pharmacologic targets or biomarkers of cancer and other reproductive diseases [7]. Increased expression of PGRs has been reported in gastric cancer [8]. Signature patterns of expression of the estrogen and PGR signaling pathways may be used to predict prognosis and guide management of colorectal cancer [9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
