Yao Jun, Qi Xing-Ling, Zhang Yong
School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China.
Cancer Hospital of China Medical University, Liaoning Cancer Hospital & Institute, Shenyang, 110042, People's Republic of China.
BMC Med Genet. 2018 Jan 25;19(1):16. doi: 10.1186/s12881-018-0529-5.
The 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.
Using 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.
Using 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.
Our 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.
孕激素受体（PGR）基因多态性在乳腺癌中的作用仍存在争议。在此，我们进行了一项荟萃分析，以确定Alu插入是否与乳腺癌风险增加相关，以及Alu插入是否促成乳腺癌的发生。
通过数据库检索，我们选择了10项符合严格纳入标准的对照病例研究；这些研究包括2106例病例和1660例对照。我们生成了比值比和95%置信区间，以确定Alu插入与乳腺癌发病率之间关系的强度。我们还进行了额外的亚组分析和敏感性分析，以进一步阐明这种关系。
使用随机效应模型，我们得出结论，在显性遗传模型下，Alu插入与乳腺癌风险无关；合并的比值比为1.025（95%置信区间=0.526 - 1.994，p = 0.943）。当根据种族进行亚组分析时，我们发现Alu插入与印度人和印欧混血种族群体的乳腺癌发病率相关，但对于白种人或拉丁裔血统的患者，这种关联消失了。
我们的荟萃分析表明，Alu插入型孕激素受体基因多态性与乳腺癌无关。这些结果提供了关于PGR基因中Alu插入与乳腺癌发病率之间关联的进一步信息。
