Altered expression profiles of microRNAs upon arsenic exposure of human umbilical vein endothelial cells.

Recent studies in our laboratory indicated that arsenite at 20μM significantly induces the apoptosis of HUVECs. In this study we analyzed miRNAs expression profiles upon arsenic exposure of these cells to explore the molecular mechanisms of arsenic-induced vascular toxicity. The expression of miRNAs was examined by Exiqon miRCURY™ LNA microRNA chips. We found that 85 miRNAs were up-regulated and 52 were down-regulated by arsenic treatment as compared to the control group. The expression of altered miRNAs was validated by quantitative reverse-transcription PCR (qRT-PCR). A number of DNA motifs were identified in the promoters of the perturbed miRNAs by promoter analysis using MEME software. Analysis of cellular functions by using DAVID Bioinformatics Resources revealed that phosphoproteins and genes involved in alternative splicing are among the top categories targeted by both up- and down-regulated miRNAs. In conclusion, the results show that the alteration of miRNAs expression might play crucial roles in arsenic-induced vascular injury.