Identification of epigenetic aberrant promoter methylation of RASSF1A in serum DNA and its clinicopathological significance in lung cancer

21014 Objective: To detect the hypermethylation status of RASSF1A promoter in serum DNA of lung cancer patients and to analyze its correlation with clinicopathological features. Methods: Serum DNA was extracted from peripheral blood from 80 primary lung cancer patients, 35 benign pulmonary disease patients and 15 healthy donors. The methylation status of RASSF1A promoter was determined using methylation-specific PCR technique, and the correlation between methylation profiles and clinicopathological parameters was statistically analyzed. Results: Aberrant methylation of RASSF1A was detected in 27 of the 80 (33.8%) patients with lung cancer but no benign pulmonary disease patients or healthy donors (p<0.001). RASSF1A was preferentially observed in small cell lung cancer (p=0.042), while no statistical difference was found among methylation frequencies of different subtypes of non-small cell lung cancer. The methylation status was also found to be associated with relative poor differentiation (p=0.009) and late stage (p=0.013), but not with gender, age or treatment. Conclusion: RASSF1A promoter is frequently hypermethylated in serum DNA of primary lung cancer patients, and RASSF1A is a promising novel biomarker for lung cancer diagnosis. No significant financial relationships to disclose.