Specific microRNA expression during chondrogenesis of human mesenchymal stem cells.

Mesenchymal stem cells (MSCs) have the capacity to self-renew and differentiate into multiple cell types, but little is known about the precise mechanism of this procedure. Recent studies show that a group of short noncoding RNAs called microRNAs (miRNAs) play a key role in this procedure. However, little work has been done to determine the miRNAs which specifically regulate the differentiation of MSCs. In this study, we cultured human MSCs and chondrogenic differentiation MSCs of 3 donors, and investigated the miRNA expression profiles of MSCs and chondrogenic differentiated MSCs from 2 donors by using miRNA microarrays. We found 5 miRNAs were significantly overexpressed in chondrogenic differentiated MSCs in each sample, and 4 were further confirmed by real-time RT-PCR assay in the sample from the third independent donor. We also predicted the confirmed miRNAs corresponding to putative target genes by online software. The results indicated that the overexpressed miRNAs in chondrogenic differentiated MSCs may play a role in the procedure of MSC chondrogenesis, which offers us guidance for further studies.