Abstract
BackgroundThe Bcl-2-associated X protein (Bax) is a proapoptotic member of the Bcl-2 family known to be activated and upregulated during apoptosis. Single nucleotide polymorphisms (SNPs) in Bax promoter may participate in the process of carcinogenesis by altering its own expression and the cancer related genes. Bax-248G>A polymorphism has been implicated to alter the risk of cancer, but the listed results are inconsistent and inconclusive. In the present study, we performed a meta-analysis to systematically summarize the possible association of this polymorphism with the risk of cancer.MethodologyWe conducted a search of case-control studies on the associations of Bax-248G>A polymorphism with susceptibility to cancer in Pub Med, Science Direct, Wiley Online Library and hand search. Data from all eligible studies based on some key search terms, inclusion and exclusion criteria were extracted for this meta-analysis. Hardy-Weinberg equilibrium (HWE) in controls, power calculation, heterogeneity analysis, Begg’s funnel plot, Egger’s linear regression test, forest plot and sensitivity analysis were performed in the present study.ResultsCancer risk associated with Bax-248G>A polymorphism was estimated by pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). The pooled ORs were calculated in allele contrast, homozygous comparison, heterozygous comparison, dominant and recessive model. Statistical significance was checked through Z and p-value in forest plot. A total of seven independent studies including 1772 cases and 1708 controls were included in our meta-analysis. Our results showed that neither allele frequency nor genotype distributions of this polymorphism were associated with risk for cancer in any of the genetic model. Furthermore, Egger’s test did not show any substantial evidence of publication bias.Conclusions/SignificanceThis meta-analysis suggests that the Bax-248G>A polymorphism is not an important cancer risk factor. Nevertheless, additional well-designed studies with larger sample size focusing on different ethnicities and cancer types are required to further validate the results.
Highlights
The specific causes of cancer are not yet known
In the initial report by Saxena et al during 2002, in a study of 25 controls and 34 chronic lymphocytic leukemia (CLL) patients they have shown that an increased genotype frequency of the Bcl-2-associated X protein (Bax)-248GA polymorphism in patient compared to controls, in higher disease stage
Genotype frequency in the control group was 5.7% for GA genotypes, which was 68.7 % for CLL in stage I-IV [30]. This finding was supported by a study of Moshynska et al in which they have demonstrated this single nucleotide polymorphisms (SNPs) as a cause of reduced Bax protein expression [31], which may be a reason of drug resistance by CLL patient
Summary
The specific causes of cancer are not yet known. epidemiological studies contribute to suggest the relationship of genetic polymorphism to cancer susceptibility. Genetic association studies with single nucleotide polymorphisms (SNPs) targeting cancer are emerging area of research. SNP analysis can be a tool for explaining the genetic complexities responsible for the cancer development to some extent. We performed a meta-analysis to systematically summarize the possible association of this polymorphism with the risk of cancer. Methodology: We conducted a search of case-control studies on the associations of Bax-248G>A polymorphism with susceptibility to cancer in Pub Med, Science Direct, Wiley Online Library and hand search. Results: Cancer risk associated with Bax-248G>A polymorphism was estimated by pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). Our results showed that neither allele frequency nor genotype distributions of this polymorphism were associated with risk for cancer in any of the genetic model. Conclusions/Significance: This meta-analysis suggests that the Bax-248G>A polymorphism is not an important cancer risk factor. Additional well-designed studies with larger sample size focusing on different ethnicities and cancer types are required to further validate the results
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
