Down-regulation of lncRNA snaR is correlated with postoperative distant recurrence of HPV-negative cervical squamous cell carcinoma.

Long non-coding RNAs (lncRNAs) snaR is a newly identified lncRNA with known functionality only in colon cancer. Our study was carried out to investigate the involvement of lncRNA snaR in human papillomaviruses (HPV)-negative cervical squamous cell carcinoma (CSCC). In the present study, plasma levels of lncRNA snaR in 108 patients with HPV-negative CSCC at stage I and II, and 35 healthy female controls were detected by real-time quantitative PCR. ROC curve analysis was performed to evaluate the diagnostic value of lncRNA snaR for HPV-negative CSCC. All patients were subjected to surgical resection and followed-up for 5 years to record cancer recurrence. lncRNA snaR expression vectors were transfected into HPV-negative CSCC cells. Cell migration and invasion ability were evaluated by Transwell migration and invasion assay, respectively. Expression levels of TGF-β1 were determined by Western blot. It was observed that lncRNA snaR was down-regulated in HPV-negative CSCC patients comparing with healthy controls. Down-regulation of lncRNA snaR effectively distinguished HPV-negative CSCC patients from healthy controls. lncRNA snaR was further down-regulated in patients with distant recurrence (DR) but not in patients with local-recurrence or without recurrence. lncRNA snaR overexpression decreased TGF-β1 expression in CSCC cells, while exogenous TGF-β1 treatment showed no significant effects on lncRNA snaR expression. lncRNA snaR overexpression inhibited cancer cell migration and invasion, while TGF-β1 treatment attenuated the inhibitory effect of lncRNA snaR overexpression on cancer cell migration and invasion. We therefore conclude that down-regulation of lncRNA snaR may induce postoperative DR of HPV-negative CSCC possibly through the interactions with TGF-β1.