TY - JOUR AB - The aim of the present study was to investigate the association between microRNA (miR)-155 and apoptosis of monocytes infected by Mycobacterium tuberculosis, to examine the effect of forkhead box O3 (FOXO3) on miR‑155. The present study analysed the apoptosis of CD14+ in the peripheral blood of patients with active tuberculosis, disposed the THP‑1 human monocytic cell line by BCG and examined the expression of miR‑155. Furthermore, the expression of FOXO3 in THP‑1 cells was determined, and wild- and mutant-type luciferase reporter plasmids containing FOXO3 3'‑untranslated regions (UTRs) were constructed to analyse the expression of luciferase. Finally, an over‑expression plasmid was constructed, and THP-1 cells were transfected with control miRNA, miR‑155 and the plasmid, which revealed that miR‑155 inhibited the apoptosis of THP‑1 cells. miR‑155 in the THP‑1 cells infected by BCG was upregulated and apoptosis also increased. However, the apoptosis declined when the cells were transfected with the control miRNA and miR‑155. Folllowing transfection with miR‑155, the expression of FOXO3 decreased. Transfection with miR‑155 and the FOXO3 3'-UTRs significantly reduced luciferase, and overexpression of FOXO3 reversed the inhibitory role of miR‑155. From these results, it was concluded that mycobacteria can improve the level of miR‑155, while BCG can induce apoptosis in THP‑1 cells. The results suggested FOXO3 is a downstream target gene of miR‑155, which combines 3'-UTRs to inhibit the expression of FOXO3. AD - Second Tuberculosis Internal Medicine Department, The First Affiliated Hospital of Xinxiang Medical University, Weihui, Henan 453100, P.R. China First Tuberculosis Internal Medicine Department, The First Affiliated Hospital of Xinxiang Medical University, Weihui, Henan 453100, P.R. China Third Tuberculosis Internal Medicine Department, The First Affiliated Hospital of Xinxiang Medical University, Weihui, Henan 453100, P.R. China AU - Huang,Jian AU - Jiao,Junhua AU - Xu,Weihua AU - Zhao,Huayang AU - Zhang,Chunxiao AU - Shi,Yan AU - Xiao,Zhijian DA - 2015/11/01 DO - 10.3892/mmr.2015.4250 EP - 7108 IS - 5 JO - Mol Med Rep KW - tuberculosis monocyte microRNA-155 FOXO3 PY - 2015 SN - 1791-2997 1791-3004 SP - 7102 ST - miR-155 is upregulated in patients with active tuberculosis and inhibits apoptosis of monocytes by targeting FOXO3 T2 - Molecular Medicine Reports TI - miR-155 is upregulated in patients with active tuberculosis and inhibits apoptosis of monocytes by targeting FOXO3 UR - https://doi.org/10.3892/mmr.2015.4250 VL - 12 ER -