New concept of the Axin2 rs2240308 polymorphism and cancer risk: an updated meta-analysis.

Previous meta-analyses reported that the variant T allele of Axin2 rs2240308 is associated with a decreased cancer risk. However, more recent findings have been inconsistent. Therefore, we carried out an updated meta-analysis to examine whether this polymorphism is still associated with a decreased cancer risk. Twelve articles, including 14 case-control studies (2,215 cases and 2,481 controls), were included in our study. Surprisingly, different from previous meta-analyses, no significant association between Axin2 rs2240308 polymorphism and cancer risk was observed (dominant model: OR=0.85; 95% CI=0.68-1.06). In further stratified analyses, rs2240308 was significantly associated with a decreased cancer risk only in Asians (dominant model: OR=0.76; 95% CI=0.66-0.88), while for Caucasians the variant showed no significant association with cancer risk (dominant model: OR=1.09; 95% CI=0.67-1.76). Moreover, the rs2240308 variant exhibited a significant association with a decreased risk of lung cancer and prostate cancer. These findings provided new evidence that differed from previous meta-analyses; Axin2 rs2240308 may not modify general cancer susceptibility. Similar with previous meta-analyses, our analysis indicated that Axin2 rs2240308 may modify cancer susceptibility in an ethnicity- and/or type-specific manner. These findings indicate that further replication studies with large sample sizes are warranted to re-evaluate the relationship between Axin2 rs2240308 and cancer risk, especially in Caucasians.