title: Association between BHMT gene rs3733890 polymorphism and cancer risk: evidence from a meta-analysis.
abstract: OBJECTIVE
  The gene betaine-homocysteine methyltransferase (BHMT) has drawn much attention during the past decades. An increasing number of clinical and genetic investigations have supposed that BHMT rs3733890 polymorphism might be associated with risk of breast cancer and ovarian cancer. As no consistent conclusion has been achieved, we conducted an up-to-date summary of BHMT rs3733890 polymorphism and cancer risk through a meta-analysis.
  
  
  METHODS
  The articles were collected from PubMed, Google Scholar, and CNKI (Chinese) databases up to December 2015. Then, the correlations were determined by reading the titles and abstracts and by further reading the full text to filter the unqualified articles. Odds ratio (OR) and the corresponding 95% confidence intervals (CI) were used to assess the results.
  
  
  RESULTS
  Among 187 articles collected in the analysis, seven studies with a total of 2,832 cases and 3,958 controls were included for evaluation of the association between BHMT rs3733890 polymorphism and susceptibility of cancer risk. The heterogeneity test showed no significant differences. Furthermore, we found that BHMT -742G>A polymorphism in case and control groups showed no statistically significant association with susceptibility in various cancer types except for uterine cervical cancer (A vs G: OR =0.641, 95% CI =0.445-0.923, P=0.017; AA+AG vs GG: OR =0.579, 95% CI =0.362-0.924, P=0.022). In addition, no statistically significant association was uncovered when stratification analyses were conducted by ethnicity and genotyping methods.
  
  
  CONCLUSIONS
  Our results have shown no obvious evidence that rs3733890 polymorphism in BHMT gene affected the susceptibility of head and neck squamous cell carcinoma, breast cancer, ovarian cancer, colorectal adenoma, and liver cancer. In contrast, we found the protective role of BHMT -742G>A polymorphism in uterine cervical cancer incidence. Future well-designed studies comprising larger sample size are warranted to verify our findings.
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Yue
authors: Y
authors: Xu
authors: First School of Clinical Medicine, Anhui Medical University, Hefei, Anhui, People's Republic of China.
authors: Cunye
authors: C
authors: Yan
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Zongyao
authors: Z
authors: Hao
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Jun
authors: J
authors: Zhou
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Song
authors: S
authors: Fan
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Sheng
authors: S
authors: Tai
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Cheng
authors: C
authors: Yang
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Li
authors: L
authors: Zhang
authors: Department of Urology, The First Affiliated Hospital of Anhui Medical University and Institute of Urology.
authors: Chaozhao
authors: C
authors: Liang
keywords: BHMT; cancer risk; meta-analysis; polymorphism; susceptibility