Article Abstract

Plasma microRNA expression in workers occupationally exposed to benzene

Authors: Yang Liu, Xianwen Chen, Yuan Shi, Jie Zhang, Hengdong Zhang, Feng Zhang, Baoli Zhu


Background: Benzene is a confirmed organic carcinogen, and one of the most common environmental pollutants. However, the mechanism underlying benzene-induced hematotoxicity and leukemogenicity has not been fully elucidated. Our study aimed to explore whether benzene exposure has an effect on the plasma microRNA (miRNA) expression.
Methods: In the discovery stage, we used a microarray assay to detect the miRNA expression profiles of two pooled plasma samples from ten healthy benzene-exposed individuals and ten non-benzene exposed controls. Subsequently, we conducted an expanded validation of three candidate miRNAs in 118 healthy benzene-exposed individuals and 91 non-exposed controls.
Results: In the discovery stage, 5 miRNAs demonstrated at least a 1‑fold higher expression, and 12 miRNAs showed at least a −1‑fold lower expression in the exposure group as compared with the expression levels in the control group. In the expanded validation stage, the plasma level of miR-638 was significantly up-regulated (2.68±0.12 vs. 1.38±0.10, P<0.01) while the plasma levels of miR-221-3p and miR-122-5p were significantly down-regulated (−0.42±0.08 vs. 1.44±0.12 for miR-221-3p and 1.91±0.10 vs. 2.86±0.13 for miR-122-5p, P<0.01) in the exposures as compared with the controls. The validation results of the three miRNAs by qRT-PCR were in concordance with the microarray analysis.
Conclusions: Our investigation suggested that benzene exposure might be related to elevated expression of miR-638 and decreased expression of miR-221-3p and miR-122-5p in human plasma.