DAPK promoter methylation status correlates with tumor metastasis and poor prognosis in patients with non-small cell lung cancer

Abstract

This meta-analysis investigated the correlation between the promoter methylation of death-associated protein kinase (DAPK) and the clinicopathological features in patients with non-small cell lung cancer (NSCLC). Scientific literature databases were exhaustively searched to retrieve published studies relevant to DAPK methylation and NSCLC. Retrieved studies published in English and Chinese languages were screened according to the stringent predefined inclusion and exclusion criteria, and high quality studies were selected for meta-analysis. All statistical analyses were performed utilizing STATA software (Version 12.0, Stata Corporation, College Station, TX, USA). A total of 14 published studies (5 in English and 9 in Chinese) were enrolled in the present meta-analysis, and contained 1238 patients with NSCLC. The results indicated that NSCLC patients with metastatic phenotype were strongly associated with significantly higher methylation rate of DAPK compared to NSCLC patients without metastasis. Additionally, in NSCLC patients carrying tumors with DAPK methylation, the 5-year survival rate was remarkedly lower than NSCLC patients without DAPK methylation. However, we did not find significant correlation between DAPK methylation and histological stage or tumor node metastasis (TNM) stage in NSCLC patients. Our meta-analysis results reveal that DAPK promoter methylation might be associated with tumor metastasis and poor prognosis in NSCLC patients, although no correlation with histological types and TNM stage in NSCLC patients were found.