Glucocorticoids induce apoptosis by inhibiting microRNA cluster miR­17­92 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. HCS­2/8 cells were selected as an in vitro model of human chondrocytes to assess the apoptosis induced by GCs and determine the role of the microRNA­17­92 (miR­17­92) cluster in the regulation of apoptosis. It was demonstrated that dexamethasone (Dex) was able to induce apoptosis and high levels of expression of apoptosis­associated molecules in HCS­2/8 chondrocytic cells, and that expression of the miR­17­92 cluster was inhibited during Dex­induced apoptosis. In conclusion, the present study suggested that inhibition of the expression of the miR­17­92 cluster contributed to the Dex­induced apoptosis in chondrocytes. The results suggest that microRNAs have an important role in glucocorticoid­induced impairment to chondrocytes.