Runx2 and microRNA regulation in bone and cartilage diseases.

The homeostasis of skeletal tissues requires tight regulation of a variety of signaling pathways, and the onset and progression of skeletal diseases are often caused by signaling abnormalities. MicroRNAs (miRNAs) are short noncoding RNA molecules that have emerged as a new dimension of gene regulation. MiRNAs have been shown to play an important role in the regulation of the differentiation of embryonic and hematopoietic stem cells. However, the role of specific miRNAs and their target genes has not been fully defined in the regulation of mesenchymal stem cells. Runx2 is a key transcription factor controlling MSC differentiation and bone and cartilage function. This article reviews work on Runx2 and miRNA regulation in bone and cartilage diseases.