Functional screening of altered microRNA expression in 3-methylcholanthrene-treated human umbilical vein endothelial cells

The common environmental contaminant 3-methylcholanthrene (3MC) is found in cigarette smoke and is produced by incomplete combustion of fat, wood and coal. 3MC is a poly aromatic hydrocarbon that interacts with an aryl hydrocarbon receptor and causes inflammation and induces vascular dysfunction; 3MC forms the DNA adducts structure and regulates cell cycle, which increase oxidative stress and inflammation. MicroRNAs (miRNAs) are non-coding RNA molecules that negatively regulate gene expression; these RNAs also play a role in cellular and molecular responses to toxicants, and can post-transcriptionally regulate gene expression. In this study, we examined whether miRNAs affect the regulation of gene expression in 3MC-treated human umbilical vein endothelial cells (HUVECs). We carried out pair-wise correlation analysis and identified 131 and 116 miRNAs with altered expression upon treatment of HUVECs with 100 nM and 1 μM 3MC, respectively. Furthermore, we identified 188 and 85 mRNAs with altered expression upon treatment with 100 nM and 1 μM 3MC; we subsequently analyzed their anti-correlations. The Gene Ontology (GO) enrichment analysis on the altered expression of miRNA-related genes displayed significant enrichment for genes involved in certain biological processes. Specifically, our results suggest that changes in miRNA expression caused by 3MC treatment are associated with inflammation of endothelial cells and may play a role in cardiovascular disease.