miR-223 Regulates Adipogenic and Osteogenic Differentiation of Mesenchymal Stem Cells Through a C/EBPs/miR-223/FGFR2 Regulatory Feedback Loop

Abstract

Several miRNAs have recently been identified to regulate adipocyte or osteoblast differentiation or both. In this study, miR-223 was found to be involved in the reciprocal regulation of adipocyte and osteoblast differentiation. miR-223 was induced in primary cultured mouse marrow stromal cell, mesenchymal line C3H10T1/2 and stromal line ST2 after adipogenic treatment. Conversely, it was reduced in preosteoblast MC3T3-E1 after osteogenic treatment. Supplementing miR-223 levels using synthetic miR-223 mimics significantly suppressed the growth of the C3H10T1/2 and ST2 cells and induced the progenitor cells to fully differentiate into adipocytes, along with induction of adipocyte-specific transcription factors peroxisome proliferator-activated receptor c, CCAAT/enhancer binding protein-a (C/EBPa), and marker genes aP2 and adipsin. By contrast, depletion of the endogenous miR-223 using synthetic miR-223 inhibitor repressed the progenitor cells to differentiate. The effects of miR-223 on adipocyte formation from ST2 cells were also demonstrated by using lentivirus that overexpresses miR-223. Conversely, supplementing miR-223 blocked ST2 to differentiate into osteoblasts. Fibroblast growth factor receptor 2 (Fgfr2), a critical regulator of osteoblast, was shown to be a direct target of miR-223 by using dual luciferase reporter assay. Knockdown of Fgfr2 in C3H10T1/2 downregulated phosphorylation of ERK1/2 and upregulated expression of C/EBPa and dramatically enhanced the differentiation of the cells into adipocytes. Further investigation of mechanisms that control miR-223 expression demonstrated that C/EBPs induced miR-223 expression through binding to the promoter regions of the miR-223. Taken together, our study provides evidences that miR-223 regulates adipocyte and osteoblast differentiation through a novel C/EBPs/miR-223/FGFR2 regulatory feedback loop. STEM CELLS 2015;33:1589-1600

Specific micro-RNA expression patterns distinguish the basal and luminal subtypes of muscle-invasive bladder cancer

“…Specifically, several basal miRNAs (miR-125b, miR-142, miR-143, miR-152, miR-155, and miR-221/222/223) have been predicted to block genes in the adipogenesis and RXR activation pathways [21-23]. Most notably, miR-125b, miR-223, miR-99a, and miR-212 target FGFR2 and FGFR3, which are involved in luminal MIBC biology [5, 22, 24, 25]. Several basal miRNAs (miR-125b, miR-142, miR-152, miR-146b, miR-222, and miR-212) have also been predicted to target luminal factors that have been previously identified in breast cancer, including ERBB2, ERBB3, ERBB4, and FOXA1 [26-28].…”

Osteogenic Differentiation of Human Amniotic Fluid Mesenchymal Stem Cells Is Determined by Epigenetic Changes

“…An increasing amount of microRNAs has been demonstrated as regulators of different aspects of bone development or osteoblast differentiation. Some of them have been reported as inhibitors of osteogenic differentiation such as miR-34a [39] or miR-223 [40] in human stromal cells. As our results expose, the effect of these microRNAs is the same in human AF-MS cells as their levels significantly decreased after osteogenic differentiation induction.…”

MicroRNA-223 Suppresses Osteoblast Differentiation by Inhibiting DHRS3

“…In the present study, we further found that DHRS3 can promote osteogenic differentiation in vitro. Recent reports have demonstrated regulatory roles for miR-223 in bone metabolism, including in mediating the repression of the key proteins required for osteoblast differentiation [29]. For instance, miR-223 downregulates osteoblast differentiation through a C/EBPα/miR-223/FGFR2 regulatory feedback loop [29].…”

“…Recent reports have demonstrated regulatory roles for miR-223 in bone metabolism, including in mediating the repression of the key proteins required for osteoblast differentiation [29]. For instance, miR-223 downregulates osteoblast differentiation through a C/EBPα/miR-223/FGFR2 regulatory feedback loop [29]. To maintain physiological bone metabolism, osteoblasts and osteoclasts coordinate with each other and maintain the balance between bone formation and resorption, which is always determined by the differentiation of osteoblasts and osteoclasts [30].…”