Identification of critical genes associated with oxidative stress pathways in benzene-induced hematotoxicity

Bone marrow failure (BMF) is chronic benzene-induced hematotoxicity, which is associated with differential gene expression abnormality. Benzene-induced BMF is characterized by irreversible bone marrow depression. Despite extensive studies have been conducted, there is a lack of reliable, useful and simple diagnostic method for BMF. Previous studies have shown that the aberrant gene expression changes and reactive oxygen species production in bone marrow cells related to the development of BMF. Early detection of differentially expressed genes (DEGs) as potential biomarkers is important for diagnosis and treatment. However, the validation of effective biomarker through DEGs analysis in benzene-induced BMF still deserve to be clarified. This study aimed to identify target genes as potential biomarkers with benzene-induced BMF based on DEGs analysis.

First, we developed a benzene-induced BMF mouse model and obtained the DEGs in bone marrow cells of benzene-exposed CD1 mice. Next, after obtaining the DEGs via RNA-Sequencing (RNA-seq) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were also used, key genes associated with benzene-induced BMF were identified. Additionally, the key markers for benzene poisoning was evaluated using qRT-PCR technique.

We identified DEGs for further KEGG functional analysis. Ten statistically significantly (up or down) regulated genes, namely Mapk11, Foxo1, Lefty1, Ren1, Bank1, Fgf3, Cdc42ep2, Rasgrf1, P2rx7, and Shank3 were found mainly associated with mitogen-activated protein kinases (MAPK) oxidative stress pathway . Further analysis using qRT-PCR identified that eight statistically significant DEGs associated with signaling pathways such as MAPK. We found that the level of mRNA expression of Mapk11, Foxo1, Bank1, Lefty1, Ren1, P2rx7, and Fgf3 genes were increased and Cdc42ep2 gene was decreased in BMF mice compared to control mice. Additionally, we validated the eight candidate genes for potential biomarkers in peripheral blood mononuclear cells of benzene poisoning patients by qRT-PCR.

Our results indicated that Mapk11 and Fgf3 were predominantly candidate genes linked to novel biomarkers for benzene hematotoxicity in human beings. Our study will provide new candidate genes as useful biomarkers involved in benzene-induced hematotoxicity.