[The relationship between FHIT gene promoter methylation and lung cancer risk: a meta-analysis]

Tumor-suppressor gene promoter DNA methylation in tumor cells is associated with its reduced expression. FHIT (fragile histindine triad) was one of the important tumor suppressor genes which was found hypermethylated in the promoter region in most of tumors. The aim of this study is to evaluate the relationship between FIHT gene promother methylation and lung cancer risk by meta-analysis.

By searching Pubmed, CNKI and Wanfang, the open published articles related to FHIT gene promoter methylation and lung carcinoma risk were collected. The odds ratio (OR) and range of FHIT gene of cancer tissue of lung cancer patients compared with normal lung tissue, plasma and the bronchial lavage fluid were pooled by statistical software Stata 11.0.

Eleven studies were finally included in this meta-analysis. The median methylation rate were P(median)=40.0% (0-68.3%), P(median)=8.7% (0-35.0%), P(media)n=33.3% (17.1%-38.3%) and P(median)=35.9% (31.1%-50.8%) in cancer tissue, NLT, BALF and plasm respectively. The pooled results showed the methylation rate in tumor tissue was much higer than that of NLT OR=5.82 (95%CI: 3.74-9.06, P<0.05), but without statistical significance for BALF OR=1.55 (95%CI: 0.89-2.70, P>0.05) and plasma OR=1.41 (95%CI: 0.90-2.20, P>0.05).

Hypermethylation of FHIT gene promoter region was found more frequent in cancer tissue than that of NLT which may demonstrated association between lung cancer risk and FHIT gene promoter methylation.