TNF-α-308G/A polymorphisms and nasopharyngeal cancer risk: a meta-analysis.

Previous evidence has indicated that the polymorphism of tumor necrosis factor-alpha (TNF-α) is a risk factor for various cancers, however, the association between TNF-α-308G/A polymorphism and nasopharyngeal carcinoma (NPC) remains controversial and ambiguous. The aim of this study is to clarify the association between TNF-α polymorphism and NPC using meta-analysis. A meta-analysis based on five eligible case-control studies involving 499 cases and 1,470 controls was carried out to summarize the data on the association between TNF-α-308G/A polymorphism and NPC risk. Odds ratios (OR) with 95 % confidence intervals (95 % CI) were used to assess the strength of this association in the fixed-effect model. The pooled analyses showed no significant association between TNF-α-308G/A polymorphism and NPC (AA vs. GG: OR = 1.38, P = 0.193; GA vs. GG: OR = 0.92, P = 0.585; GA + AA vs. GG: OR = 1.00, P = 0.972; AA vs. GA + GG: OR = 1.44, P = 0.138). We also categorized by geographic location (non-Asian or Asian) for subgroup analysis; the results also showed no significant association between TNF-α-308G/A polymorphism and NPC risk in all of the comparisons. No publication bias was observed in this study (t = -0.11, P = 0.918, 95 % CI = -4.893-4.559). No significant association was found between TNF-α-308G/A polymorphism and the risk for NPC.