ABCG2 C421A Polymorphism and Imatinib Response in Chronic Myeloid Leukemia: A Systematic Review and Meta-Analysis

OBJECTIVE: To estimate the association between ABCG2 C421A polymorphism and response to imatinib in chronic myeloid leukemia. METHODS: A systematic review was conducted to evaluate the effect of ABCG2 C421A polymorphism on imatinib response. The databases of PubMed, Embase, Web of science, CINAHL with FullText, and Cochrane Library were searched for all published studies from inception to December 2015. The following terms were used with functions of 'AND' and 'OR': 'chronic myeloid leukemia', 'CML', 'drug transporter', 'ABCG2', 'BCRP', 'polymorphisms', 'SNPs', and 'imatinib'. The studies reporting the association between ABCG2 polymorphism and imatinib response were evaluated. RESULTS: A total of 7 studies were included in the present meta-analysis. The pooled analysis showed that ABCG2 c.421CC genotype was significantly associated with poor response to imatinib under the dominant model (CC vs CA+AA; OR: 0.56; 95% CI: 0.41, 0.77; p = 0.0004). The subgroup analysis of Asian studies demonstrated a significantly lower response in c.421CC genotype than in c.421CA or c.421AA genotype (OR: 0.52; 95% CI: 0.37, 0.73; p = 0.0002). In subgroup analyses of 5 studies, the patients with the c.421CC genotype exhibited higher risk for worse response than the patients with c.421CA or c.421AA genotype (heterozygote codominant model: CC vs. AC; OR: 0.49, 95% CI: 0.33, 0.73; p = 0.0006; homozygote codominant model: CC vs AA; OR: 0.43; 95% CI: 0.25, 0.75, p = 0.003). CONCLUSION: The ABCG2 c.421CC genotype was significantly associated with poor response to imatinib compared to the c.421CA and c.421AA genotypes in chronic myeloid leukemia, especially in Asian patients.

Effect of Ginseng on Blood Pressure: A Systematic Review and Meta-Analysis

OBJECTIVE: A meta-analysis was performed to determine effect of ginseng on blood pressure. METHODS: The databases of PubMed, Embase, Cochrane Library, RISS, DBpia, KISS, and Koreamed were searched for all published studies from inception to January 2016. The following terms were used: "ginseng", "hypertension", and "blood pressure". Using the Review Manager 5, mean differences (MDs) were pooled to measure the effect of ginseng on blood pressure compared to that of placebo. RESULTS: Eleven randomized controlled trials were included. In this meta-analysis, ginseng treatment significantly lowered systolic blood pressure (SBP) in a dose-independent way (MD: -1.99, p = 0.04). In subgroup analysis, 8-12 week consumption of ginseng achieved significantly greater reduction in SBP (MD: -3.14, p = 0.03), while single administration of ginseng failed to show BP-lowering effect. When ingested over 8-12 weeks, ginseng significantly lowered diastolic blood pressure (DBP) (MD: -1.96, p = 0.03). No significant association was found between ginseng dose and the magnitude of BP-lowering effect. However, a significant positive relationship was observed between baseline SBP level and the magnitude of SBP reduction (r = 0.848, p = 0.033). Such a relationship was not seen in DBP. CONCLUSION: Consumption of ginseng for 8-12 weeks achieved significant reductions in SBP and DBP in a dose-independent way. There was a significant positive relationship between baseline SBP level and the magnitude of SBP reduction.