RT Journal Article SR Electronic T1 The up-regulation of TGF-β1 by miRNA-132-3p/WT1 is involved in inducing leukemia cells to differentiate into macrophages JF bioRxiv FD Cold Spring Harbor Laboratory SP 2024.06.13.598949 DO 10.1101/2024.06.13.598949 A1 Wang, Zhimin A1 Wang, Chaozhe A1 Zhang, Danfeng A1 Wang, Xidi A1 Wu, Yunhua A1 Sun, Ruijing A1 Sun, Xiaolin A1 Li, Qing A1 Bi, Kehong A1 Jiang, Guosheng YR 2024 UL http://biorxiv.org/content/early/2024/06/17/2024.06.13.598949.abstract AB Although it has been shown that abnormal expression of Wilm’s tumor gene 1 (WT1) is associated with the occurrence of leukemia, the specific mechanism via which it induces leukemia cells to differentiate into macrophages remains poorly understood. Based on the prediction that the microRNA miRNA-132-3p is the miRNA that possibly lies upstream of the WT1 gene, we hypothesized that miRNA-132-3p may participate in the polarization process of macrophages through regulating expression of the WT1 gene. The focus of the present study was therefore to investigate the role of the miRNA-132-3p/WT1 signaling axis in the differentiation of THP-1 leukemia cells into macrophages induced by PMA. The results obtained indicated that, compared with the control group, the proliferation of THP-1 cells was clearly inhibited by PMA, and the cell cycle was arrested at G0/G1 phase, associated with an upregulation of CD11b and CD14 expression. Induced by PMA, the expression level of miRNA-132-3p was increased, WT1 expression was decreased, and the expression level of TGF-β1 was increased. Following transfection with miRNA-132-3p mimics, however, the expression of WT1 in the THP-1 cells was downregulated, with upregulation of the CD11b and CD14 antigens, whereas this downregulation of WT1 mediated by miRNA-132-3p mimics could be reversed by co-transfection with WT1 vector, which was accompanied by downregulation of the CD11b and CD14 antigens. The luciferase activity of the co-transfected miRNA-132-3p mimic + WT1-wild-type (WT) group was found to be statistically significantly lower compared with that of the co-transfected miRNA-132-3p mimic + WT1-mutated (MUT) group. Furthermore, chromatin immunoprecipitation experiments showed that WT1 was able to directly target the promoter of the downstream target gene TGF-β1, which led to the negative modulation of TGF-β1 expression, whereas downregulation of WT1 led to an upregulation of the expression of TGF-β1, which thereby promoted the differentiation of THP-1 cells into macrophages. Taken together, the present study has provided evidence, to the best of the authors’ knowledge for the first time, that the miRNA-132-3p/WT1/TGF-β1 axis is able to regulate the committed differentiation of leukemia cells into macrophages.Competing Interest StatementThe authors have declared no competing interest.