A Meta-Analysis of the Relationship Between RARβ Gene Promoter Methylation and Non-Small Cell Lung Cancer

Background: Hypermethylation of CpG islands in tumor suppressor gene plays an important role in carcinogenesis. Many studies have demonstrated that hypermethylation in promoter region of RAR beta gene could be found with high prevalence in tumor tissue and autologous controls such as corresponding non-tumor lung tissue, sputum and plasma of the NSCLC patients. But with the small number subjects included in the individual studie, the statistical power is limited. Accordingly, we performed this meta-analysis to further asses the relationship of methylation prevalence between the cancer tissue and atuologous controls (corresponding non-tumor lung tissue, sputum and plasma). Methods: The published articles about RAR beta gene promoter hypermethyltion were identified using a systematic search strategy in PubMed, EMBASE and CNKI databases. The pooled odds ratio (OR) of RAR beta promoter methylation in lung cancer tissue versus autologous controls were calculated. Results: Finally, eleven articles, including 1347 tumor tissue samples and 1137 autologous controls were included in this meta-analysis. The pooled odds ratio of RAR beta promoter methylation in cancer tissue was 3.60 (95% CI: 2.46-5.27) compared to autologous controls with random-effect model. Strong and significant correlation between tumor tissue and autologous controls of RAR beta gene promoter hypermethylation prevalence across studies (Correlation coefficient 0.53) was found. Conclusion: RAR beta promoter methylation may play an important role in carcinogenesis of the NSCLC. With significant methylation prevalence correlation between tumor tissue and autologous of this gene, methylation detection may be a potential method for searching biomarker for NSCLC.