Meta-analysis: tumour invasion-related genetic polymorphisms and gastric cancer susceptibility

Background  Host genetic susceptibility has been suggested as one of the most important possible explanations for interindividual difference in gastric cancer (GC) risk.
Aim  To evaluate the impact of tumour invasion-related gene polymorphisms, which may be involved in a variety of processes during GC development, such as cell adhesion and angiogenesis, on the risk of GC.
Methods  We reviewed published studies on tumour invasion-related gene polymorphisms and GC susceptibility until 31 March 2008, and then quantitatively summarized associations of the most widely-studied polymorphism, CDH1 −160C>A, with GC using meta-analysis.
Results  Twenty-seven eligible studies were included in this review. Fourteen polymorphisms significantly related to GC in at least one study were identified. For several polymorphisms, heterogeneous results were observed and associations in opposite directions were seen among Asian and Caucasian populations. In meta-analysis, CDH1 −160C>A showed an inverse association with GC among Asians (OR, 0.76; 95% CI, 0.55–1.05) and a positive association among Caucasians (OR, 1.40; 95% CI, 0.95–2.04).
Conclusions  This review suggests that genetic polymorphisms in tumour invasion could be candidate biomarkers of GC risk. However, differences between populations and stages of cancer need to be taken into account and may explain some of the inconsistencies found in previous studies.