Lack of Association Between CYP1A1 Polymorphisms and Risk of Bladder Cancer: a Meta-analysis

Background: The effects of CYP1A1 gene polymorphisms on the risk of bladder cancer (BC) remaincontroversial. We carried out a meta-analysis to clarify the role of CYP1A1 gene polymorphisms in BC. Materialand
Methods: A comprehensive literature search was conducted up to November 20, 2013. Odds ratios (ORs) with95% confidence intervals (CIs) were used to estimate the strength of the association. Meta-regression, subgroupanalysis, sensitivity analysis and publication bias were also performed.
Results: Eight studies involving 1,059BC cases and 1,061 controls were included. The meta-analysis showed that there was no significant associationbetween the two common mutations of CYP1A1 and BC risk. For the I1e462Val A/G polymorphism with GG vs.AA the OR was 1.47 (95 % CI= 0.70-3.07, P =0.308). For the MspI T/C polymorphism, though a slight trend wasfound this was not statistically nonsignificant (CC vs.TT, OR = 1.24, 95 % CI= 0.98-1.58, P =0.078). Subgroupanalyses by ethnicity also found no obvious association between CYP1A1 and BC risk.
Conclusion: The presentmeta-analysis suggests that CYP1A1 polymorphism is not associated with bladder cancer risk.