Relationship between DNA Methylation in Long Non-Coding RNA ANRIL and Coronary Artery Disease

Objective: To explore the association between ANRIL promoter methylation level and coronary artery disease development. Subject and method: The methylation status of ANRIL promote in 100 subjects with coronary artery disease patients and matched controls who underwent coronary angiography was quantitatively analyzed on Sequenom MassARRAY. KEGG pathway enrichment analyses were performed to identify the functions and pathways possibly influenced by the genes nearest the ANRIL promoter CpG sites in subjects with CAD compared with the controls. Result: Results indicate 7 to 8 CpG sites within the 2nd CpG island located at the upstream of  CDKN2B-AS1 is hyper-methylated in CADs compared with the matched controls (p=0.034), 40th CpG sites within the 2nd CpG island located at the upstream of  CDKN2B-AS1 is lower-methylated in CADs compared with the matched controls (p=0.045). The Pearson or Spearman analyses indicated that methylation level of 7 to 8 CpG sites within the 2nd CpG island was significantly associated with TCH (r=-0.204, p=0.004), HDL-C (r=0.165, p=0.020), and LDL-C (r=0.265, p=0.000), and the methylation level of 40th CpG sites within the 2nd CpG island was significantly associated with age (r=-0.147, p=0.037) and fasting blood glucose (r=-0.178, p=0.012). KEGG pathway analysis revealed a significant enrichment of genes associated with the TNF signaling pathway. Among them, the C/EBPbeta was identified as key transcription factor to promote the expression of CDKN2B-AS1 through interaction with their promoters. Conclusion: Expression levels of the ANRIL promoter DNA methylation were significantly associated with the CAD development in this population. Further KEGG pathway enrichment analyses suggested that C/EBPbeta has been identified as key transcription factor to promote the expression of CDKN2B-AS1 through interaction with their promoters via TNF signaling pathway. Funding Statement: the National Natural Science Foundation of China (grantsNo. 30400173, 30971257, and 81170180) and the Priority Academic Program Development of Jiangsu Higher Education Institutions. Declaration of Interests: There was not any conflict of interest existing in this manuscript. Ethics Statement: The study was performed based on the case-control principle in accordance with the protocol approved by the ethics committee of the First Affiliated Hospital of Nanjing Medical University and the Friendship Hospital of Ili Kazakh Autonomous Prefecture in China.