Association between Genetic Variants of Transforming Growth Factor-β1 and Susceptibility of Pneumoconiosis: A Meta-analysis

BACKGROUND Transforming growth factor-beta 1 (TGF-β1) and gene variants have been extensively studied in various human diseases. For example, TGF-β1 polymorphisms were associated with fibrosis and pneumoconiosis, but the data remained controversial. The aim of this meta-analysis was to assess the association between TGF-β1 -509 C>T [rs1800469], +869 T>C [rs1800470], and +915 G>C [rs1800471] polymorphisms and pneumoconiosis. METHODS A comprehensive literature search was conducted through searching in PubMed, Embase, the Chinese Biomedical Database, and the Wei Pu (Chinese) Database by the end of April 2016. Eleven publications with 21 studies were included in this meta-analysis, covering a total of 4333 patients with pneumoconiosis and 3478 controls. Study quality was assessed, and heterogeneity and publication bias were measured. All statistical analyses were performed using STATA version 12.0 (StataCorp, College Station, TX, USA) software. RESULTS The data showed significant associations between TGF-β1 -509 C>T polymorphism and the risk of pneumoconiosis development (T vs. C, odds ratio [OR] = 1.35, 95% confidence interval [CI]: 1.00-1.81, P = 0.046); between TGF-β1 +915 G>C polymorphism and the pneumoconiosis risk (C vs. G, OR = 1.69, 95% CI: 1.19-2.40, P = 0.004; CG vs. GG, OR = 1.79, 95% CI: 1.23-2.60, P = 0.002; CC+CG vs. GG, OR = 1.80, 95% CI: 1.24-2.61, P = 0.002). In addition, the subgroup analysis of ethnicity versus pneumoconiosis types indicated a significant association of silicosis among Asian populations but not that of coal workers' pneumoconiosis in Caucasian populations. In contrast, no significant association was exhibited between TGF-β1 +869 T>C polymorphism and risk of pneumoconiosis. CONCLUSION The polymorphisms of both TGF-β1 -509 C>T and +915 G>C are associated with increased risk of pneumoconiosis.