lncRNAs MALAT1 and LINC00657 upstream to miR-214-3p/BMP2 regulate osteogenic differentiation of human mesenchymal stem cells.

Background: Osteogenic differentiation of human mesenchymal stem cells (hMSCs) holds significant clinical implications for patients with bone diseases. LncRNAs are an emerging group of epigenetic modulators involved in the osteogenesis of hMSCs. In this study, we explored lncRNA profiles that are upstream to the hsa-miR-214-3p/BMP2 axis in osteogenic differentiation of hMSCs.

Method: HMSCs were induced toward osteogenesis for 14 days. Between day 1 and day 14, qRT-PCR was conducted to compare the expressions of BMP2, Runx2, hsa-miR-214-3p, and biochemical assays to compare alkaline phosphatase and Alizarin Red S activities. 145 lncRNAs, which were experimentally confirmed upstream to hsa-miR-214-3p were examined. Five significantly upregulated lncRNAs, MEG3, SNHG16, FAM83H-AS1, MALAT1 and LINC00657 were downregulated in differentiated hMSCs and their impact on osteogenic differentiation were examined. Hsa-miR-214-3p was silenced in lncRNAs-downregulated hMSCs to further examine the association between lncRNAs and hsa-miR-214-3p/BMP2 axis.

Results: From day 1 to day 14, hMSCs underwent significant osteogenic differentiation, and KCNQ1OT1, MEG3, SNHG16, FAM83H-AS1, MALAT1 and LINC00657 were significantly upregulated. Downregulations of MEG3, SNHG16, FAM83H-AS1, MALAT1 and LINC00657 all suppressed osteogenic differentiation. However, qRT-PCR and RIP assay demonstrated that only MALAT1 and LINC00657 acted through hsa-miR-214-3p/BMP2 to regulate osteogenic differentiation. Furthermore, silencing hsa-miR-214-3p only rescued osteogenic differentiation in MALAT1- or LINC00657- downregulated hMSCs.

Conclusions: Our data strongly indicated that lncRNAs MALAT1 and LINC00657 acted through miR-214-3p/BMP2 axis to regulate osteogenic differentiation of hMSCs.