title: Association between L55M polymorphism in Paraoxonase 1 and cancer risk: a meta-analysis based on 21 studies.
abstract: L55M polymorphism in Paraoxonase 1 (PON1) has been regarded as a risk factor for many cancer types. Nevertheless, the results remain controversial and inconclusive. We therefore performed a meta-analysis of all eligible case-control studies to evaluate the association between L55M polymorphism and cancer risk. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the associations. Finally, a total of 5,627 cases and 6,390 controls, arising from 21 case-control studies, were enrolled in our study. Significant associations between PON1-L55M polymorphism and overall cancer risk were identified in all genetic models. In the stratified analyses by cancer type, PON1-L55M polymorphism was a risk factor for breast cancer in all genetic models, prostate cancer in the heterozygote model (ML vs LL: OR =1.304, 95% CI =1.049-1.620, P heterogeneity=0.067), and ovarian cancer in the recessive model (MM vs ML/LL: OR =1.526, 95% CI =1.110-2.097, P heterogeneity=0.464). Similarly, an increased risk was also identified for the Caucasian population in the heterozygote comparison and homozygote models, and hospital-based controls in all genetic models. To sum up, our study suggests that the PON1-L55M allele increased the risk of cancer. Future well-designed studies with larger sample sizes are warranted to further verify these findings.
authors.affiliation: Department of Urology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Urology, Anhui Medical University Graduate School, Hefei, Anhui, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.affiliation: Department of Urology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China.
authors.forename: Lu
authors.initials: L
authors.lastname: Fang
authors.affiliation: Department of Urology, The Second Hospital of Lanzhou University, Lanzhou, People's Republic of China.
authors.forename: Hu
authors.initials: H
authors.lastname: Xiong
authors.affiliation: Department of Anatomy, School of Basic Medical Sciences, Southern Medical University, Guangzhou, People's Republic of China.
authors.forename: Xun
authors.initials: X
authors.lastname: Wu
authors.affiliation: Department of Urology, Anhui Medical University Graduate School, Hefei, Anhui, People's Republic of China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Urology, Anhui Medical University Graduate School, Hefei, Anhui, People's Republic of China.
authors.forename: Song
authors.initials: S
authors.lastname: Wu
authors.affiliation: Department of Urology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China.
authors.forename: Dexin
authors.initials: D
authors.lastname: Yu
keywords: L55M; Paraoxonase 1; cancer; meta-analysis; polymorphism