Lingli Sun

Dietary fiber intake reduces risk for Barrett's esophagus and esophageal cancer

ABSTRACT Background: Observational studies suggest an association between dietary fiber intake and risk of Barretts esophagus and esophageal cancer. However, the results are inconsistent. Objective: To conduct a meta-analysis of observational studies to assess this association. Design: All eligible studies were identified by electronic searches in PubMed and Embase through February 2015. Dose–response, subgroup, sensitivity, and publication bias analyses were performed. Results: A total of 15 studies involving 16,885 subjects were included in the meta-analysis. The pooled odds ratio for the highest compared with the lowest dietary fiber intake was 0.52 (95% CI, 0.43–0.64). Stratified analyses for tumor subtype, study design, geographic location, fiber type, publication year, total sample size, and quality score yielded consistent results. Dose–response analysis indicated that a 10-g/d increment in dietary fiber intake was associated with a 31% reduction in Barretts esophagus and esophageal cancer risk. Sensitivity analysis restricted to studies with control for conventional risk factors produced similar results, and omission of any single study had little effect on the overall risk estimate. Conclusions: Our findings indicate that dietary fiber intake is inversely associated with risk of Barretts esophagus and esophageal cancer. Further large prospective studies are warranted.

Chromosome 4q25 Variants and Age at Onset of Ischemic Stroke

Recent genome-wide association studies have identified two variants rs10033464 and rs2200733 on chromosome 4q25, significantly associated with ischemic stroke risk. We conducted this study to investigate whether these two variants were associated with age at onset and prognosis of ischemic stroke in a Chinese population. Genotyping of rs10033464 and rs2200733 was performed by improved multiple ligase detection reaction. One-way ANOVA was used to compare the mean age of ischemic stroke onset for each variant. Combined effects of these two variants on age at ischemic stroke onset were then estimated. Kaplan-Meier method, log-rank test, and the Cox proportional hazards regression models were used to assess the effect of the two variants on ischemic stroke prognosis. A total of 914 ischemic stroke patients were included in the study. Rs10033464 and rs2200733 were not associated with ischemic stroke recurrence (P > 0.05). However, rs10033464 TT genotype was significantly correlated with early age of ischemic stroke onset (60.76 for GG, 61.74 for GT, 55.47 for TT, TT vs. GT: P = 0.043). Combined effects analysis revealed that mean age at ischemic stroke onset decreased with increasing genetic risk score (P = 0.038). The findings indicated that the chromosome 4q25 variants might associate with early age at onset of ischemic stroke. Further larger studies in other populations are warranted to validate our results.

Association between PTGS1 polymorphisms and functional outcomes in Chinese patients with stroke during aspirin therapy: Interaction with smoking

PURPOSE Prostaglandin-Endoperoxide Synthase 1 (PTGS1) and smoking may play important roles in aspirin nonresponsiveness, but the effect of their interaction on stroke outcomes remains largely unknown. We examined the effects of PTGS1 polymorphisms, smoking status, and their interaction on functional outcomes in a cohort of Chinese Han patients with stroke during aspirin therapy. METHODS A total of 617 ischemic stroke patients taking aspirin were enrolled. Three single nucleotide polymorphisms (SNPs) rs1330344, rs3842788, and rs5788 in PTGS1 were determined for genotyping. Poor functional outcomes were defined as a modified Rankin Scale (mRS) of 3-6 at 90-day follow-up. The influence of PTGS1 gene-smoking interaction on functional outcomes was examined. RESULTS Poor functional outcomes occurred in 145 (23.5%) patients. When adjusting multiple factors by logistic regression, CC genotype of rs1330344 was associated with poor functional outcomes (risk ratio [RR]=1.73; 95% confidence interval [CI]: 1.17-2.37). A similar connection was found in the CGC haplotype (RR=1.40; 95% CI: 1.08-1.77). Furthermore, we found a significant interaction between rs1330344 and smoking status (Pinteraction=0.018); the interaction effect between the PTGS1 haplotype and smoking also showed statistical significance (Pinteraction=0.040). CONCLUSIONS In Chinese Han stroke patients with aspirin therapy, the adverse effect of PTGS1 polymorphisms on functional outcomes may be modulated by the smoking status. PTGS1 gene-smoking interaction might in part reflect the heterogeneity in the prognosis of patients treated with aspirin.

A Study of GWAS-Supported Variants of rs9943582 in a Chinese Han Population with Ischemic Stroke: No Associations with Disease Onset and Clinical Outcomes

BACKGROUND The variant rs9943582 of APLNR (apelin receptor) was identified by a large-scale study to be associated with an increased risk of ischemic stroke in a Japanese population. We conducted this study to investigate the association between the variant and age of onset and clinical outcomes of ischemic stroke in a Chinese population. METHODS Improved multiple ligase detection reaction was used to genotype the variant. We compared the mean age at ischemic stroke onset with one-way ANOVA. The Kaplan-Meier method, log-rank test, and Cox proportional hazards regression models were performed to analyze the association between the variant and clinical outcomes (recurrence and death). RESULTS A total of 916 ischemic stroke patients were recruited for the study. For age at ischemic stroke onset, no significant association was identified with the variant in any genetic model. In addition, the variant was not strongly associated with recurrence and death risk of ischemic stroke, as shown by the results. CONCLUSIONS The findings indicated that the variant rs9943582 was not associated with age at onset and clinical outcomes of ischemic stroke. However, evidence from well-designed studies with larger and in different ethnic populations are warranted to further explore the effects of APLNR on the ischemic stroke onset and clinical outcomes.

CDKN2B Methylation and Aortic Arch Calcification in Patients with Ischemic Stroke

Aim: CDKN2A/2B near chromosome 9p21 has been proposed as a potential genetic etiology for both atherosclerosis and arterial calcification. DNA methylation, which can change the expression of CDKN2A/2B, may be an underlying mechanism for this association. This study aimed to evaluate whether CDKN2A/2B methylation is related to aortic arch calcification (AAC) in patients with ischemic stroke. Methods: DNA methylation levels of CDKN2A/2B was measured using venous blood samples in 322 patients with ischemic stroke. A total of 36 CpG sites around promoter regions of CDKN2A/2B were examined. AAC was quantified with Agatston score based on results of computed tomography angiography. Results: There were 248 (77.0%) patients with and 74 (23.0%) patients without evident AAC. Compared with patients without AAC, patients with AAC had higher methylation levels of CDKN2B (5.72 vs 4.94, P < 0.001). Using a generalized linear model, positive correlation between methylation levels and log-transformed calcification scores was detected at CDKN2B (β = 0.275 ± 0.116, P = 0.018). Conclusion: Patients with higher levels of DNA methylation of CDKN2B may bear increased risk for AAC. Further studies to reveal the underlying mechanisms of this association are warranted for establishing a cause–effect relationship.