Glucocorticoids induce apoptosis by inhibiting microRNA cluster miR-17-92 expression in chondrocytic cells

Abstract

Sustained treatment with glucocorticoids (GCs) has frequently been observed to impair skeletal development. However, the influence of GCs on chondrocytes, which have a key role in skeletal development, has been rarely reported. HCS-2/8 cells were selected as an in vitro model of human chondrocytes to assess the apoptosis induced by GCs and determine the role of the microRNA-17-92 (miR-17-92) cluster in the regulation of apoptosis. It was demonstrated that dexamethasone (Dex) was able to induce apoptosis and high levels of expression of apoptosis-associated molecules in HCS-2/8 chondrocytic cells, and that expression of the miR-17-92 cluster was inhibited during Dex-induced apoptosis. In conclusion, the present study suggested that inhibition of the expression of the miR-17-92 cluster contributed to the Dex-induced apoptosis in chondrocytes. The results suggest that microRNAs have an important role in glucocorticoid- induced impairment to chondrocytes.