Association between PTEN Gene IVS4 Polymorphism and Risk of Cancer: A Meta-Analysis

BACKGROUND Phosphatase and tensin homolog (PTEN) is a well established tumor suppressor gene. Recently, increasing studies investigated the association between PTEN IVS4 polymorphism (rs3830675) and risk of various types of cancer. However, the results from the individual studies were controversial. The aim of this meta-analysis was to elucidate whether PTEN IVS4 polymorphism was associated with cancer risk. METHODS Databases including PubMed, Web of knowledge and Chinese National Knowledge Infrastructure (CNKI) were systematically searched to identify potentially eligible literatures. Odds ratios (OR) and their 95% confidence interval (CI) were used to assess the strength of association between PTEN IVS4 polymorphism and cancer risk. RESULTS A total of seven case-control studies were finally included in this meta-analysis. The pooled analysis suggested that individuals with PTEN IVS4 (-/-) genotype were significantly associated with increased risk of cancer (OR = 1.45, 95% CI = 1.19-1.76, P<0.001) and subgroup of digestive tract cancer (OR = 1.67, 95% CI = 1.28-2.18, P<0.001) compared with (+/+) genotype. The allele analysis revealed that (-) allele was significantly associated with increased risk of cancer (OR = 1.30, 95% CI = 1.12-1.50, P = 0.001) and subgroup of digestive tract cancer (OR = 1.42, 95% CI = 1.16-1.74, P = 0.001) compared with (+) allele. No significant association was observed between PTEN IVS4 (+/-) genotype and risk of cancer. CONCLUSION PTEN IVS4 (-/-) genotype was significantly associated with increased risk of cancer especially for digestive tract cancer compared with (+/+) genotype. The (-) allele of PTEN IVS4 (rs3830675) polymorphism was significantly associated with increased risk of cancer especially for digestive tract cancer compared with (+) allele. The recessive effect model and dominant effect model also demonstrated significant association between PTEN IVS4 (rs3830675) polymorphism and increased cancer risk especially for digestive tract cancer. Further large-scale and well-designed studies regarding different ethnicities are still required to confirm the results of our meta-analysis.