Background: DICER, one of the microRNA (miRNA) biogenesis proteins, is involved in the maturation ofmiRNAs and is implicated in cancer development and progression. The results from previous epidemiologicalstudies on associations between DICER rs1057035 polymorphism and cancer risk were inconsistent. Thereforeweperformed this meta-analysis to summarize possible associations. Materials and
Methods: We searched allrelevant articles on associations between DICER rs1057035 polymorphism and cancer risk from PubMed,EMBASE, Chinese Biomedical Literature and Chinese National Knowledge Infrastructure until August 2014.Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess any associations. Heterogeneitytests, sensitivity analyses and publication bias assessments were also performed in this meta-analysis. All analyseswere conducted using STATA software.
Results: Seven case-control studies, including 4,875 cancer cases and 7,800controls were included in the meta-analysis. Overall, the results indicated that the C allele of DICER rs1057035polymorphism was significantly associated with decreased cancer risk in allelic comparison, heterozygote anddominant genetic models (C vs T: OR=0.88, 95%CI 0.81-0.95, p=0.002; TC vs TT: OR=0.85, 95%CI 0.77-0.93,p=0.001; CC/TC vs TT: OR=0.86, 95%CI 0.78-0.94, p=0.001). In the subgroup analysis by ethnicity, a significantlydecreased cancer risk was found in Asian but not Caucasian populations.
Conclusions: The present meta-analysissuggests that the C allele of the DICER rs1057035 polymorphism probably decreases cancer risk. However, thisassociation may be Asian-specific and the results should be treated with caution. Further well-designed studiesbased on larger sample sizes and group of populations are needed to validate these findings.