Original Article
Analysis of plasma microRNA expression profiles in a Chinese population occupationally exposed to benzene and in a population with chronic benzene poisoning
Abstract
Background: Circulating microRNA (miRNA) has attractive interests as a non-invasive biomarker of physiological and pathological conditions. Our study aimed to investigate the potential effects of chronic benzene poisoning (CBP) and benzene exposure on miRNA expression, and identify CBP-related miRNAs.
Methods: In the discovery stage, we used a microarray assay to detect the miRNA expression profiles among pooled plasma samples from ten CBP patients, ten healthy benzene-exposed individuals and ten non-benzene exposed individuals. Subsequently, we conducted an expanded validation of six candidate miRNAs in 27 CBP patients- low blood counts, 54 healthy benzene-exposed individuals and 54 non-exposed individuals. Moreover, we predicted the biological functions of putative target genes using a Gene Ontology (GO) function enrichment analysis and KEGG pathway analysis.
Results: In the discovery stage, compared with non-exposures, 36 and 12 miRNAs demonstrated at least a 1.0-fold differential expression in the CBP patients and the benzene exposures, respectively. And compared with benzene exposures, 58 miRNAs demonstrated at least a 1.0-fold differential expression in the CBP patients. In the expanded validation stage, compared with non-exposures as well as exposures, miR-24-3p and miR-221-3p were significantly up-regulated (1.99- and 2.06-fold for miR-24-3p, 2.19- and 3.93-fold for miR-221-3p, P<0.01) while miR-122-5p and miR-638 were significantly down-regulated (−3.45- and −2.60-fold for miR-122-5p, −1.82- and −3.20-fold for miR-638, P<0.001) in the CBP patients; compared with non-exposures, the plasma level of miR-638 was significantly up-regulated (1.38-fold, P<0.01) while the plasma levels miR-122-5p and miR-221-3p were significantly down-regulated (−0.85- and −1.74-fold, P<0.01) in the exposures, which were consistent with the results of microarray analysis.
Conclusions: The four indicated plasma miRNAs may be biomarkers of indicating responses to benzene exposure. Further studies are warranted to verify our findings with a large sample and to confirm the underlying mechanisms.
Methods: In the discovery stage, we used a microarray assay to detect the miRNA expression profiles among pooled plasma samples from ten CBP patients, ten healthy benzene-exposed individuals and ten non-benzene exposed individuals. Subsequently, we conducted an expanded validation of six candidate miRNAs in 27 CBP patients- low blood counts, 54 healthy benzene-exposed individuals and 54 non-exposed individuals. Moreover, we predicted the biological functions of putative target genes using a Gene Ontology (GO) function enrichment analysis and KEGG pathway analysis.
Results: In the discovery stage, compared with non-exposures, 36 and 12 miRNAs demonstrated at least a 1.0-fold differential expression in the CBP patients and the benzene exposures, respectively. And compared with benzene exposures, 58 miRNAs demonstrated at least a 1.0-fold differential expression in the CBP patients. In the expanded validation stage, compared with non-exposures as well as exposures, miR-24-3p and miR-221-3p were significantly up-regulated (1.99- and 2.06-fold for miR-24-3p, 2.19- and 3.93-fold for miR-221-3p, P<0.01) while miR-122-5p and miR-638 were significantly down-regulated (−3.45- and −2.60-fold for miR-122-5p, −1.82- and −3.20-fold for miR-638, P<0.001) in the CBP patients; compared with non-exposures, the plasma level of miR-638 was significantly up-regulated (1.38-fold, P<0.01) while the plasma levels miR-122-5p and miR-221-3p were significantly down-regulated (−0.85- and −1.74-fold, P<0.01) in the exposures, which were consistent with the results of microarray analysis.
Conclusions: The four indicated plasma miRNAs may be biomarkers of indicating responses to benzene exposure. Further studies are warranted to verify our findings with a large sample and to confirm the underlying mechanisms.
