Signature of circular RNAs in peripheral blood mononuclear cells from patients with active tuberculosis

The study was to characterize the expression profiles of circular RNAs (circRNAs) in peripheral blood mononuclear cells (PBMCs) from active tuberculosis (TB) patients and to investigate their function. Microarray was applied to detect circRNA expression and reverse transcription-quantitative polymerase chain reaction was conducted to validate the microarray results. Meanwhile, receiver operating characteristic curve (ROC) curve was calculated to evaluate the predictive power of the selected circRNAs for TB diagnosis. Additionally, circRNA/miRNA interaction was predicted based on miRNA target prediction software, and gene ontology as well as Kyoto Encyclopedia of Genes and Genomes pathway analysis were used to predict their biological function. In total, 171 circRNAs were found to be dysregulated in TB samples. Specifically, circRNA_103017, circRNA_059914 and circRNA_101128 were confirmed to be increased, while circRNA_062400 was decreased in TB samples. ROC analysis revealed that circRNA_103017 had potential value for TB diagnosis, followed by circRNA_059914 and circRNA_101128. Moreover, circRNA_101128 expression in TB samples was negatively correlated with the level of its possible target let-7a and bioinformatics analysis showed that circRNA_101128 was potentially involved in MAPK and P13K-Akt pathway possibly via modulation of let-7a. Taken together, our results indicated that some dysregulated circRNAs were potential biomarkers for the diagnosis of TB and circRNA_101128-let-7a interplay may play considerable role in PBMCs response to Mtb infection.