Transcriptomic analyses of human bronchial epithelial cells BEAS-2B exposed to brominated flame retardant (tetrabromobisphenol A)

Brominated flame retardants (BFRs) are supposed to act as disruptors of cell signaling, but the underlying mechanisms remain less clear. Human bronchial epithelial cells (BEAS-2B) were used to investigate the toxic effect and gene expression changes induced by tetrabromobisphenol A (TBBPA). By genome-wide approaches with Illumina RNA-seq, 87 genes were identified to exhibit ≥1.5-fold changes in expression after treatment by TBBPA for 48 h, among which, 79 were upregulated and 8 were downregulated. Gene ontology (GO) annotation enriched unigenes were divided into three clusters: biological process (BP), cellular component (CC) and molecular function (MF). Pathway analysis showed that NF-κB, TNF signaling, toll-like receptor, MAPK signaling and B-cell receptor were the most prominent pathways affected by TBBPA, which play key roles in regulating cell proliferation and cell differentiation, inflammatory response. Finally, for verifying the accuracy of microarray analysis, qRT-PCR was used to analyze the transcription level of key genes in the above signaling pathways, and ELISA assay confirmed the effect of TBBPA on the levels of CXCL-2, CCL-3, CCL-4, IL-1β, TNF-α, and IL-6. These findings provided important information for further exploitation of the mechanisms under-lying BFR-induced adverse health effects.