Metaanalysis Of Assocation Between TGFB1and TGFBRⅡ Gene Polymorphismsand Risk Of Gastric Cancer

objective In recent years, several studies have reported theassociation of the transforming growth factor β1(TGFβ1) gene promoterregion-509gene polymorphism and transforming growth factor β receptorII (TGFβRII) gene promoter region-875gene polymorphism and risk ofgastric cancer (GC). However, results remain inconclusive. Therefore, Weperformed a meta-analysis to explore the association of TGFβ1-509andTGFβRII-875gene polymorphism and susceptibility to gastric cancer fromall eligible case-control studies published to date.Methods To search published case-control studies on the associationsof TGFβ1-509and TGFβRII-875gene polymorphisms and susceptibility togastric cancer, we conducted a computerized literature search of EMBASE,PUBMED, Wan fang database, VIP Information, China NationalKnowledge Infrastructure (CNKI) database and so on. Moreover, stratifiedanalysis was made according to ethnicity from different countries. Twoinvestigators independently selected the literatures based on the criteria forinclusion and extracted the data and reached a consensus on all items. Results A total of ten case-control studies were collected in theMeta-analysis study, including3481gastric cancer patients and3783controls. Our results suggested that TGFβ1-509polymorphism wassignificantly increased risk of gastric cancer. The TT homozygote had asignificantly increased gastric cancer risk (OR=1.19,95%CI:1.07-1.32;P＜0.01) as compared with the C-allele carriers (CT or TTgenotypes). But we did not find that the TGFβ1-509polymorphism wasassociated with gastric cancer risk in a TT versus CC codominant model(OR=1.15,95%CI=0.86-1.54; P=0.35; Phet＜0.05), in a CT versus CCcodominant model (OR=0.99,95%CI=0.72-1.36; P=0.97; Phet＜0.05), in aTT+CT vs CC dominant model (OR=1.05,95%CI=0.78-1.42;P=0.74;Phet＜0.05), respectively. In the subgroup analysis by ethnicity(Asian and Caucasian), we found that the TGFβ1-509polymorphism wasassociated with gastric cancer risk in a TT versus CT+CC recessive modelamong Asian populations (OR=1.20,95%CI=1.08–1.34;P＜0.01). Therewere three eligible case-control studies for the TGFβRII-875polymorphism,including1837gastric cancer patients and1760controls. Our resultssuggested that TGFβRII-875polymorphism was significantly decreased riskof gastric cancer. The AA homozygote had a significantly decreased gastriccancer risk (OR＝0.66,95%CI＝0.46-0.94;P＝0.02) as compared with theG-allele carriers (AG or GG genotypes). We also showed that significantassociations for AAvs GG model (OR＝0.57,95%CI＝0.40-0.81; P＜0.01; Phet＝0.40); AG vs GG model (OR＝0.64,95%CI＝0.55-0.74; P＜0.01;Phet＝0.28); AG+AA vs GG model (OR＝0.63,95%CI＝0.55-0.73;P＜0.01; Phet＝0.53).Conclusions The meta-analysis showed that the TT allele carriers ofthe TGFβ1-509polymorphism would be a risk factor of gastric cancer,especially in Asian populations. And the present study also indicated thatTGFβRII-875polymorphism might be a protective factor for thedevelopment of gastric cancer among Asian populations.