Restoration of WT1/miR-769-5p axis by HDAC1 inhibition promotes MMT reversal in mesenchymal-like mesothelial cells

Abstract

Histone acetylation/deacetylation play an essential role in modifying chromatin structure and in regulating cell plasticity in eukaryotic cells. Therefore, histone deacetylase (HDAC) pharmacological inhibitors are promising tools in the therapy of fibrotic diseases and in cancer. Peritoneal fibrosis is a pathological process characterized by many cellular and molecular alterations, including the acquisition of invasive/pro-fibrotic abilities by mesothelial cells (MCs) through induction of mesothelial to mesenchymal transition (MMT). The aim of this study was to characterize the molecular mechanism of the antifibrotic role of HDAC1 inhibition. Specifically, treatment with MS-275, an HDAC1-3 inhibitor previously known to promote MMT reversal, induced the expression of several TGFBRI mRNA-targeting miRNAs. Among them, miR-769-5p ectopic expression was sufficient to promote MMT reversal and to limit MC migration and invasion, whereas miR-769-5p silencing further enhanced mesenchymal gene expression. These results were confirmed by HDAC1 genetic silencing. Interestingly, miR-769-5p silencing maintained mesenchymal features despite HDAC1 inhibition, thus indicating that it is necessary to drive MMT reversal induced by HDAC1 inhibition. Besides TGFBRI, miR-769-5p was demonstrated to target SMAD2/3 and PAI-1 expression directly. When analyzing molecular mechanisms underlying miR-769-5p expression, we found that the transcription factor Wilms’ tumor 1 (WT1), a master gene controlling MC development, binds to the miR-769-5p promoter favoring its expression. Interestingly, both WT1 expression and binding to miR-769-5p promoter were increased by HDAC1 inhibition and attenuated by TGFβ1 treatment. Finally, we explored the significance of these observations in the cell-to-cell communication: we evaluated the ability of miR-769-5p to be loaded into extracellular vesicles (EVs) and to promote MMT reversal in recipient mesenchymal-like MCs. Treatment of fibrotic MCs with EVs isolated from miR-769-5p over-expressing MCs promoted the down-regulation of specific mesenchymal targets and the reacquisition of an epithelial-like morphology. In conclusion, we highlighted an HDAC1-WT1-miR-769-5p axis potentially relevant for therapies aimed at counteracting organ fibrosis.

Mechanisms of mesothelial cell response to viral infections: HDAC1-3 inhibition blocks poly(I:C)-induced type I interferon response and modulates the mesenchymal/inflammatory phenotype

“…Treatment of MCs with MS-275 was confirmed to revert the EMT/MMT state toward an epithelial-like phenotype, as previously demonstrated in biological contexts not related to viral infections ( Shah et al., 2014 ; Rossi et al., 2018 ; Bontempi et al., 2022 ). The apparently paradoxical observation of induction of Snail in a frame of MMT reversal may be interpreted with the help of a previous study showing upregulated Snail expression coupled with functional inactivation upon MS-275 treatment in MCs ( Rossi et al., 2018 ).…”

Long non-coding RNA DLX6-AS1 is the key mediator of glomerular podocyte injury and albuminuria in diabetic nephropathy by targeting the miR-346/GSK-3β signaling pathway

“…However, a number of challenges still need to be addressed to achieve these goals. But it is promising and feasible in the future thanks to the latest breakthroughs in the biotechnology of gene therapy [ 24 , 75 , 76 ].…”

Recent advances in extracellular vesicles for therapeutic cargo delivery

“…However, there has been a recent increase in intensive research focusing on miRNAs, and it is anticipated that significant advances will be made in their therapeutic potential 61 . Bontempi et al loaded miR-769-5p into mesothelial cell-derived exosomes, inhibiting organ fibrosis by blocking the mesothelial-to-mesenchymal transition 62 . Bheri et al loaded miR-126 into cKit+ progenitor cells to ameliorate myocardial infarction 63 .…”