Effects of cartilage progenitor cells and microRNA-140 on repair of osteoarthritic cartilage injury

To summarize the effect of cartilage progenitor cells (CPCs) and microRNA-140 (miR-140) on the repair of osteoarthritic cartilage injury, and analyze their clinical prospects. The recent researches regarding the CPCs, miR-140, and repair of cartilage in osteoarthritis (OA) disease were extensively reviewed and summarized. CPCs possess the characteristics of self-proliferation, expression of stem cell markers, and multi-lineage differentiation potential, and their chondrogenic ability is superior to other tissues-derived mesenchymal stem cells. CPCs are closely related to the development of OA, but the autonomic activation and chondrogenic ability of CPCs around the osteoarthritic cartilage lesion cannot meet the requirements of complete cartilage repair. miR-140 specifically express in cartilage, and has the potential to activate CPCs by inhibiting key molecules of Notch signaling pathway and enhance its chondrogenic ability, thus promoting the repair of osteoarthritic cartilage injury. Intra-articular delivery of drugs is one of the main methods of OA treatment, although intra-articular injection of miR-140 has a significant inhibitory effect on cartilage degeneration in rats, it also exhibit some limitations such as non-targeted aggregation, low bioavailability, and rapid clearance. So it is a good application prospect to construct a carrier with good safety, cartilage targeting, and high-efficiency for miR-140 based on articular cartilage characteristics. In addition, CPCs are mainly dispersed in the cartilage surface, while OA cartilage injury also begins from this layer, it is therefore essential to emphasize early intervention of OA. miR-140 has the potential to activate CPCs and promote the repair of cartilage injury in early OA, and it is of great clinical significance to further explore the role of miR-140 in OA etiology and to develop new OA treatment strategies based on miR-140.