title: Meta-analysis of transforming growth factor β receptor I 6A/9A gene polymorphism and breast cancer risk: the picture remains murky.
abstract: Breast cancer is currently the second most common cancer worldwide and the most frequent malignant tumor among women. However, the exact contribution of various allelic alterations remains unclear. This meta-analysis was conducted to evaluate the association of the transforming growth factor β receptor I 6A/9A (TβR-I 6A/9A) gene polymorphism with breast cancer risk. Relevant studies were identified from PubMed and Cochrane Library on 1 October 2013, and eligible reports were recruited and synthesized. Eleven reports that included a total of 12 studies were recruited into this meta-analysis for the association of the TβR-I 6A/9A gene polymorphism and breast cancer risk. The results indicated that overall the TβR-I 6A allele was associated with breast cancer risk (OR = 1.33, 95% CI: 1.02-1.73, p = 0.04). However, the TβR-I 6A/6A and 9A/9A genotypes were not associated with an increased risk of developing breast cancer (6A/6A: OR = 1.71, 95% CI: 0.95-3.08, p = 0.07; 9A/9A: OR = 0.82, 95% CI: 0.66-1.02, p = 0.08). In the Caucasian population, no such association could be established. In conclusion, the TβR-I 6A allele might represent a risk factor for breast cancer risk, but significantly larger data sets from a larger number of studies, including studies that allow ethnicity, subgroup analysis and environmental impact evaluation, are required to maximize statistical significance and meta-analysis robustness.
authors.affiliation: a Department of Clinical Laboratory, The Affiliated Tumor Hospital of Guangxi Medical University , Nanning , China .
authors.forename: Chao
authors.initials: C
authors.lastname: Ou
authors.affiliation: b Department of Physical Diagnosis, The Affiliated Tumor Hospital of Guangxi Medical University , Nanning , China .
authors.forename: Hang
authors.initials: H
authors.lastname: Li
authors.affiliation: c Department of Emergency, The First Affiliated Hospital of Guangxi Medical University , Nanning , China .
authors.forename: Jiang-Hua
authors.initials: JH
authors.lastname: Liu
authors.affiliation: d Cellular Stress and Ageing Program, Bionanoscience and Bio-Imaging Program, Bio&Nano-Solutions , Düsseldorf , Germany , and.
authors.forename: Gregor P C
authors.initials: GP
authors.lastname: Drummen
authors.affiliation: a Department of Clinical Laboratory, The Affiliated Tumor Hospital of Guangxi Medical University , Nanning , China .
authors.forename: Bo
authors.initials: B
authors.lastname: Zhu
authors.affiliation: a Department of Clinical Laboratory, The Affiliated Tumor Hospital of Guangxi Medical University , Nanning , China .
authors.forename: Ling-Sha
authors.initials: LS
authors.lastname: Huang
authors.affiliation: a Department of Clinical Laboratory, The Affiliated Tumor Hospital of Guangxi Medical University , Nanning , China .
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.affiliation: e Department of Hepatobiliary Surgery, The Affiliated Tumor Hospital of Guangxi Medical University , Nanning , China.
authors.forename: Le-Qun
authors.initials: LQ
authors.lastname: Li
mesh_terms: D000483:Alleles; D001943:Breast Neoplasms / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D000077293:Receptor, Transforming Growth Factor-beta Type I; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics*; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D018125:Receptors, Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I
keywords: 6A/9A; breast cancer; gene polymorphism; meta-analysis; transforming growth factor β receptor I