1.
Association between cytosolic serine hydroxymethyltransferase (SHMT1) gene polymorphism and cancer risk: a meta-analysis.
Wang, Q, Lu, K, Du, H, Zhang, Q, Chen, T, Shu, Y, Hua, Y, Zhu, L
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie. 2014;(6):757-62
Abstract
BACKGROUND The serine hydroxymethyltransferase (SHMT1) is the key enzyme in the folate metabolic pathway to provide one-carbon unit that plays an important role in biosynthesis. Abnormal biosynthesis involved in DNA synthesis and methylation can lead to activation of oncogenes and inactivation of tumor suppressor genes. And the abnormal biosynthesis is closely related to a variety of common tumors' occurrence and development. A SNP in SHMT1 C1420T may effect the procession of biosynthesis and finally influence cancer occurrence. METHODS Comprehensive searches were performed on PubMed and EMBASE database. We used odds ratio (OR) and 95% confidence interval (95% CI) to assess the strength of associations between SHMT1 C1420T polymorphism and cancer risk. Q-test, I(2), and funnel plot were used to assess the heterogeneity and publication bias. RESULTS Totally, 19 studies containing 9799 cases and 11,841 controls were performed in this meta-analysis. The results showed that there was no association between SHMT1 C1420T polymorphism and cancer risk. But in the subgroup analysis, the significant associations were found in colorectal cancer and Asian population. Publication bias was not observed in the analysis. CONCLUSIONS Our results indicate that the SHMT1 C1420T polymorphism do not have a significant association with the risk of cancer overall. Otherwise, SHMT1 C1420T polymorphism may have a protective effect on colorectal cancer and Asian population.
2.
Associations between vitamin D receptor polymorphisms and susceptibility to ulcerative colitis and Crohn's disease: a meta-analysis.
Xue, LN, Xu, KQ, Zhang, W, Wang, Q, Wu, J, Wang, XY
Inflammatory bowel diseases. 2013;(1):54-60
Abstract
BACKGROUND Several polymorphisms have been identified in the vitamin D receptor (VDR) gene, while their roles in the incidence of ulcerative colitis (UC) and Crohn's disease (CD) are conflicting. This meta-analysis was designed to clarify the impact of these polymorphisms on UC and CD risk. METHODS The PubMed, Embase, and Cochrane electronic databases were searched from February 1995 to August 2011 for studies on the four VDR polymorphisms: TaqI, BsmI, FokI, and ApaI. Data were extracted and pooled odd ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS Nine studies were included. In Asians, the ff genotype of FokI was associated with increased UC risk (OR = 1.65; 95% CI, 1.11- 2.45). The "a" allele carrier status of ApaI appeared to be a protective factor for CD (OR = 0.81; 95% CI, 0.67-0.97). The tt genotype increased the risk of CD in Europeans (OR = 1.23; 95% CI, 1.02-1.49). Moreover, the tt genotype of TaqI in males had a moderate elevated risk of UC (OR = 1.56; 95% CI, 1.02-2.39) and CD (OR = 1.84; 95% CI, 1.19-2.83). CONCLUSIONS The meta-analysis reveals a significant increase in CD risk for Europeans carrying TaqI tt genotype and a significant decrease in CD risk for all carriers of the Apal "a" allele. For Asians, the VDR FokI polymorphism appears to confer susceptibility to UC. For males, the TaqI tt genotype is associated with susceptibilities to both UC and CD. Our study explored the genetic risk prediction in UC and CD, and may provide valuable insights into IBD therapy.
3.
SULT1A1 Arg213His polymorphism, smoked meat, and breast cancer risk: a case-control study and meta-analysis.
Lee, H, Wang, Q, Yang, F, Tao, P, Li, H, Huang, Y, Li, JY
DNA and cell biology. 2012;(5):688-99
Abstract
SULT1A1 is involved in both detoxification of estrogens and bioactivation of carcinogens in smoked meat. SULT1A1 Arg213His polymorphism's effect on breast cancer risk is still unclear. We recruited 400 case-control pairs to investigate the association between SULT1A1 genotypes and breast cancer risk, and the combined effect of SULT1A1 polymorphism and daily intake of smoked meat. Participants were questioned about their dietary habits and other risk factors, and their SULT1A1 genotypes were determined. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated by multivariable unconditional logistic regression. We also performed a meta-analysis of relevant published studies to test these associations. In the case-control study, no significant associations were observed between SULT1A1 polymorphism and breast cancer risk. In the meta-analysis, SULT1A1 His/His genotype slightly increased risk among both overall and postmenopausal women (OR(pooled-overall)=1.12, 95% CI: 1.02-1.24; OR(pooled-post)=1.17, 95% CI: 1.03-1.32). A larger positive association was observed in Asian populations (OR(pooled-Asian)=2.01, 95% CI: 1.24-3.26). In our case-control study, high energy-adjusted daily intake of smoked meat was significantly associated with breast cancer risk in overall, pre- and postmenopausal women (aORs: 2.31-3.13, OR 95% CIs exclude 1). High smoked meat intake interacted positively with the His variant allele (all γ>1). These results correlated with those of the meta-analysis (γ(pooled-overall)=1.27). The SULT1A1 His/His genotype may increase the risk of breast cancer among Asian women, and dietary exposure to heterocyclic amines and polycyclic aromatic hydrocarbons, along with the SULT1A1 His/His variant genotype, may synergistically increase the risk of breast cancer.