XPA A23G polymorphism and lung cancer risk: a meta-analysis

Abstract

Case-control studies on the association between XPA A23G and lung cancer have provided either controversial or inconclusive results. To clarify the effect of XPA A23G on the risk of lung cancer, a meta-analysis of all case-control observational studies was performed. Pooled odds ratios (ORs) for various polymorphisms were estimated using random and fixed effects models. The Q-statistic was used to evaluate the homogeneity, and Egger and Begg tests were used to assess publication bias. For the homozygote GG and G allele carriers (GA + GG), the pooled ORs were 1.24 (95% CI 1.05-1.46; P = 0.27 for heterogeneity) and 1.30 (95% CI 1.13-1.51; P = 0.45 for heterogeneity) compared to the homozygous genotype (AA). In the stratified analysis by ethnicity, the ORs of the G allele carriers and the homozygote GG were 1.28 (95% CI 1.10-1.49; P = 0.07 for heterogeneity) and 1.42 (95% CI 1.04-1.93; P = 0.39 for heterogeneity) among non-Caucasians. No significant associations were found in the Caucasian population in any of the genetic models. When studies that were not in Hardy-Weinberg equilibrium (HWE) were corrected, the pattern of the results remained the same. Our results indicated a significantly decreased risk of lung cancer in non-Caucasians with the G allele.

Association between XPA gene rs1800975 polymorphism and susceptibility to lung cancer: a meta‐analysis

“…There was no evidence showing correlation between XPA A23G polymorphism and lung cancer in Caucasians, which was the same with the meta-analysis performed by Zou et al 6 The above results showed XPA significant ethnic differences, which was one of the major causes of heterogeneity between studies. Therefore, we cautiously thought that actually AG gene carrier had protective effect on lung cancer risk compared with AA gene carrier in allover, especially in Asians.…”

“…Therefore, we cautiously thought that actually AG gene carrier had protective effect on lung cancer risk compared with AA gene carrier in allover, especially in Asians. There was no evidence showing correlation between XPA A23G polymorphism and lung cancer in Caucasians, which was the same with the meta-analysis performed by Zou et al 6 The above results showed XPA significant ethnic differences, which was one of the major causes of heterogeneity between studies. Evidence from several studies supports the role of DNA repair systems in monitoring and repairing carcinogeninduced DNA.…”

“…The meta-analysis with seven researches performed by Kiyohara et al 5 included four Caucasian studies in 2007. Compared with Zou et al, 6 69.2% more lung cancer cases have been included in this research. Moreover, the two studies 2,19 that deviated from the HWE were excluded, which indicated genotyping errors or population stratification.…”

“…However, the association of the XPA gene polymorphism with the risk of lung cancer has been investigated in the past decade with conflicting results. The metaanalysis by Zou et al 6 indicated significantly decreased risk of lung cancer in non-Caucasians with the G allele. Zienolddiny et al 4 suggested that the GG genotype were associated with a significantly increased risk of lung cancer compared with the GA 1 AA genotypes in Norwegians.…”

“…The meta-analysis by Kiyohara et al 5 showed XPA 23 GG genotype have protective effect on lung cancer. The metaanalysis by Zou et al 6 indicated significantly decreased risk of lung cancer in non-Caucasians with the G allele. So different views on the XPA attracted us to perform the genetic association study.…”