RNA-Seq Based Transcriptome Analysis of Endothelial Differentiation of Bone Marrow Mesenchymal Stem Cells

Objective: The aim was to identify the change in gene expression between mesenchymal stem cells (MSCs) and induced endothelial cells (ECs) and to investigate the potential mechanism of endothelial differentiation based on ribonucleic acid sequencing (RNA-Seq) analysis. Methods: MSCs were isolated from bone marrow and exposed to inducing medium. The dynamic transcription profiles of MSCs were identified and ECs were induced through RNA-seq. Differentially expressed genes (DEGs) were identified. Enrichment of functions and signalling pathways analysis were performed based on Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Quantitative real time polymerase chain reaction (qRT-PCR) was used to validate the genes selected from RNA-Seq. Results: In total, 2769 DEGs were identified, of which 1117 genes were upregulated and 1652 genes were downregulated. GO and KEGG pathway analyses identified significantly enriched pathways in DEGs, including extracellular matrix organisation, blood vessel morphogenesis, angiogenesis, extracellular matrix binding, growth factor binding and glycosaminoglycan binding extracellular matrixereceptor interaction pathway, cytokineereceptor interaction pathway and transforming growth factor (TGF)-beta signalling pathway. All genes found to be associated with the TGF-beta pathway were significantly downregulated. Eleven novel genes were also identified that most likely are involved in endothelial differentiation and were upregulated with more than 10 fold change, which were further validated by qRT-PCR. Conclusion: The GO and KEGG analysis revealed that extracellular matrix, cytokines and the TGF-beta pathway play an important role in the process of endothelial differentiation. Furthermore, 11 genes were found that may be involved in the differentiation of MSCs into ECs and contribute to current understanding of the differentiation mechanism.