Circular RNA expression profiles are significantly altered in mice bone marrow stromal cells after total body irradiation

The development of circular RNA (circRNA) microarrays has facilitated studies on the role of circRNAs in regulating gene expression through a circRNA-miRNA-mRNA network. In our study, a microarray was used to detect the expression profiles of circRNAs in mouse bone marrow stromal cell (MSCs) after total body irradiation (TBI) in an X-ray field. Forty mice were randomly distributed into two groups, the control group and the TBI group, with 20 mice in each. Using circRNA microarray data, we compared the circRNA expression profiles in the MSCs between the two groups. Randomly chosen differentially expressed circRNAs were validated as potential TBI biomarkers. Overall, 148 circRNAs were significantly upregulated while the other 133 were downregulated between the TBI group and the sham group. Among them, two upregulated circRNAs (mmu_circRNA_011235 and mmu_circRNA_016901) and three downregulated circRNAs (mmu_circRNA_008488, mmu_circRNA_000551 and mmu_circRNA_005365) exhibited trends comparable to microarray data in the validation experiments. The miRNA support vector regression method was used to predict potential target miRNAs for the circRNAs while ClueGO was used for functional analysis of predicted miRNA target genes. This is the first study to investigate the differential circRNA expression profile in TBI and the associated functions. Significantly upregulated or downregulated circRNAs may represent novel biomarkers and novel therapeutic targets for the clinical management of radiation injury with TBI.