Transforming Growth Factor Beta-1 C-509T Polymorphism and Cancer Risk: A Meta-analysis of 55 Case-control Studies

Aim: To investigate the association of transforming growth factor-beta 1 (TGF-β1) C-509T polymorphismand susceptibility to cancer by means of meta-analysis.
Methods: An extensive search was performed to identifyeligible case-control studies investigating such a link. The strength of the association between TGF-β1 C-509Tpolymorphism and cancer risk was assessed by pooled odds ratios (ORs) and 95%confidence intervals (95%CIs)in fixed or random effects models.
Results: 55 published case-control studies with a total number of 21,639 casesand 28,460 controls were included. Overall, there was no association between TGF-β1 C-509T and cancer risk inall genetic comparison models (TT vs. CC: OR=1.01, 95%CI=0.89-1.15; T vs. C: OR=1.01, 95%CI=0.94-1.07).However, a stratified analysis by cancer type indicated -509 T allele was significantly associated with decreasedrisk of colorectal cancer (CRC) (TT vs. CT/CC: OR=0.85, 95%CI=0.76-0.95), especially for Caucasians (TT vs.CT/CC: OR=0.83, 95%CI=0.71-0.98) and for population-based studies (TT vs. CT/CC: OR=0.78, 95%CI=0.68-0.89).
Conclusion: This meta-analysis suggested that TGF-β1 C-509T polymorphism might contribute to adecreased risk on colorectal cancer susceptibility, especially for Caucasians.