CircVCAN regulates the proliferation and apoptosis of osteoarthritis chondrocyte through NF-κB signaling pathway.

ABSTRACT

OBJECTIVE: Osteoarthritis is one of the chronic diseases with a high incidence. CircRNA is a circular non-coding RNA. Studies show that CircRNA is closely relevant to the pathogenesis of OA chondrocytes. However, the specific principle is still unclear. PATIENTS AND METHODS: 38 patients with OA tissues and 38 patients with normal knee cartilage in our hospital were selected, respectively. The mRNA expression levels of CircVCAN were measured by quantificational real-time polymerase chain reaction (qRT-PCR). Cell proliferation was detected by the Cell Counting Kit (CCK8). Cell cycle and apoptosis of OA chondrocytes were measured by flow cytometry. qRT-PCR and western blot were used to detect PCNA, p50, p52, p65 mRNA and protein expression levels. RESULTS: CircVCAN was highly expressed in OA tissues and OA chondrocytes. Cell proliferation and PCNA expression levels decreased significantly after transfection with si-CircVCAN in OA-chondrocytes. However, there was a significant increase on OA chondrocytes after transfection with LV-CircVCAN. Compared with the si-NC group, the apoptosis rate of OA chondrocytes was significantly increased after transfection with si-CircVCAN. The proportion of G0/G1 phase in the cell cycle was significantly reduced and the proportion of S phase was significantly increased. On the contrary, the apoptosis rate was significantly reduced after transfection with LV-CircVCAN. The proportion of G0/G1 phase in the cell cycle was significantly increased and the proportion of S phase was significantly reduced. The mRNA and protein levels of p50, p52 and p65 were significantly increased after transfection of LV-CircVCAN in OA-chondrocytes. Furthermore, PDTC (NF-κB inhibitor) transfection can significantly reverse the effect of overexpression of CircVCAN on the proliferation and apoptosis of OA chondrocytes. CONCLUSIONS: CircVCAN is overexpressed in OA tissues and cells. CircVCAN can affect the proliferation and apoptosis of OA chondrocytes by blocking the activation of the NF-κB signaling pathway. Thus, CircVCAN may be an important target molecule for OA treatment.