Identification of Expression Pattern and Clinical Significance of the Small Cajal Body-specific RNA SCARNA16 in Hepatocellular Carcinoma

Background and Aims: For high morbidity and mortality, hepatocellular carcinoma (HCC) becomes a major health issue worldwide. Nowadays, numerous non-coding RNAs (ncRNAs) are known to regulate the occurrence and pathogenesis of tumors. Some ncRNAs have also been developed as tumor biomarkers and therapeutic targets. However, the potential function of the small Cajal body-specific RNA (scaRNA) SCARNA16, a newly identified ncRNA, remains to be explored in HCC. Methods: In both HCC cell lines and specimens from 120 enrolled patients, the expression values of SCARNA16 were detected. We divided patients into SCARNA16 high and low expression subgroups, and then analyzed the difference of various clinical characteristics and prognosis data between subgroups. Results: Compared to paired controls, SCARNA16 was significantly down-regulated in HCC cell lines and clinical specimens (p<0.01). Besides, HCC patients with lower SCARNA16 expression commonly presented with larger and more tumor lesions, more vessel carcinoma emboli, more capsular invasion and higher TNM stages (p<0.05). Moreover, SCARNA16 expression was negatively correlated with postoperative prognosis of HCC patients in 5-year follow-up, including tumor-free survival (TFS) (median time of low vs. high subgroups: 14 vs. 48 months, p=0.006) and overall survival (OS) (median time of low vs. high subgroups: 39 vs. 52 months, p=0.001). Besides, SCARNA16 acted as an independent prognostic biomarker in TFS (hazard ratio [HR]: 0.578, 95% CI: 0.345- 0.969, p=0.038) and OS (HR: 0.366, 95% CI: 0.178-0.752, p=0.006). Conclusions: Low expression patterns of SCARNA16 remarkably associated with severe clinical status and poor survival of patients, suggesting that SCARNA16 possesses potency as a novel biomarker for HCC.