The long noncoding RNA SNHG1 promotes nucleus pulposus cell proliferation through regulating miR-326 and CCND1

Aberrant nucleus pulposus cell proliferation is implicated in the development of intervertebral disk degeneration (IDD). Recent studies have suggested that long noncoding RNAs (lncRNAs) can modulate cell proliferation in several pathological conditions. Here, we indicate that expression of SNHG1 was upregulated in IDD tissues compared with control tissues and that higher SNHG1 expression was associated with disk degeneration grade. In addition, we show that ectopic expression of SNHG1 promoted nucleus pulposus (NP) cell proliferation and increased the PCNA and cyclin D1 expression in NP cells. Ectopic expression of SNHG1 inhibited miR-326 expression in nucleus pulposus cells and promoted CCND1 expression, which is a direct target gene of SNHG1. Moreover, we demonstrate that expression of miR-326 was downregulated in IDD tissues compared with control tissues and that lower SNHG1 expression was associated with disk degeneration grade. Expression of miR-326 was negatively associated with SNHG1 expression in disk degeneration tissues. Overexpression of miR-326 inhibited NP cell growth and inhibited PCNA and cyclin D1 expression in NP cells. Furthermore, we show that overexpression of SNHG1 promoted nucleus pulposus cell proliferation through inhibiting miR-326 expression. These data shed novel light on the role of SNHG1 in the pathogenesis of IDD.