Tumour necrosis factor alpha -308G/A polymorphism and risk of the four most frequent cancers: a meta-analysis

Abstract

The latest data show that breast, prostate, lung and colorectal cancer are the four most frequent cancers in both sexes worldwide. A number of molecular epidemiological studies have been conducted to examine the association between TNF alpha -308G/A and the risk of those cancers. However the results have been inconclusive or inconsistent. We then performed a meta-analysis to derive a precise estimation of this association. We carried out a comprehensive search in Medline, EMBASE, OVID and Chinese Biomedical Literature Database for studies using related keywords. The inclusion criteria were (i) in English or Chinese; (ii) case-control study on this association; (iii) provide usable genotype frequencies; and (iv) sufficient published data for estimating an odds ratio (OR) with 95% confidence interval (CI). ORs and 95% CIs were calculated to assess the strength of this association under homozygote comparison (AA vs GG), heterozygote comparison (GA vs GG), dominant (AA/GA vs GG) and recessive (AA vs GA/GG) genetic model comparison. Thirty case-control studies with a total number of 16,507 cases and 19,749 controls were selected for analysis. Overall, no significant association was found between this polymorphism and the risk of total four cancers (GA vs GG: OR=1.02, 95% CI=0.91-1.14, P=0.78). However, there was a significant association between this polymorphism and breast cancer risk in western populations (GA vs GG: OR=0.91, 95% CI=0.85-0.96, P=0.002). This meta-analysis also revealed that this polymorphism was not associated with susceptibility to the other three cancers.

Tumor Necrosis Factor-A Polymorphisms and Colorectal Cancer Risk: A Meta-Analysis

“…However, both of the two previous meta-analyses focused on TNF-a 308 polymorphism claimed that it was not significantly associated with risk of colorectal cancer [22], [23], which appears in contradiction with the results of other cancers [19]–[21]. Considering the small sample size of both the two meta-analyses (1,708 and 1,742, respectively), whether TNF-a 308 polymorphism is associated with colorectal cancer remains inconclusive.…”

The relationship between tumor necrosis factor-α polymorphisms and gastric cancer risk: An updated meta-analysis

“…So far, polymorphisms at 238 (rs361525), 308 (rs1800629), 857 (rs1799724), and 1031 (rs1799964) positions were all reported to be related with risk of cancer (3,45), but all the conclusions are still in controversial and the results of previous relevant studies were ambiguous. Up to now, at least five meta-analyses about the relationships between TNF -α polymorphisms and gastric cancer risks have been published, and even those meta-analyses held inconsistent opinions (3,46–48). Furthermore, to the best of the authors' knowledge, no systematic review about all the above five SNPs has been published yet.…”

Tumor Necrosis Factor-α 238 G/A Polymorphism and Risk of Hepatocellular Carcinoma: Evidence from a Meta-analysis

“…As an important inflammatory factor, the polymorphisms in TNF-α gene have been largely studied, and TNF-α polymorphisms have been suggested to be associated with risks of many diseases, including rheumatoid arthritis, ankylosing spondylitis, and hepatitis B (Marcos et al, 2009;Postal et al, 2011). There are also many studies suggesting TNF-α polymorphisms are associated with risks of cancers, however, most them focus on the TNF-α -308 polymorphism (Fan et al, 2011;Wang et al, 2011). The relation between TNF-α -238 polymorphism and risk of cancer has not been well assessed.…”

“…There are several common single nucleotide polymorphisms (SNP) in the TNF-α gene, including −238 (rs361525), −308 (rs1800629), −857 (rs1799724), and −1031 (rs1799964) positions, which could regulate TNF-α transcription and production (Qidwai et al, 2011). It has been well demonstrated that those SNPs can affect the functions of relevant proteins and further influence the host susceptibility to various cancers (Fan et al, 2011;Wang et al, 2011). Many epidemiological studies have evaluated the association between TNF-α 238 G/A polymorphism and hepatocellular carcinoma risk (Heneghan et al, 2003;Wang et al, 2003;Niro et al, 2005;Jeng et al, 2007;Kummee et al, 2007;Jeng et al, 2009;Wang et al, 2010b;Chen et al, 2011).…”