Published online Jan 7, 2021. doi: 10.3748/wjg.v27.i1.55
Peer-review started: August 25, 2020
First decision: September 12, 2020
Revised: October 27, 2020
Accepted: November 13, 2020
Article in press: November 13, 2020
Published online: January 7, 2021
Processing time: 127 Days and 10.3 Hours
Accumulating evidence has revealed that several long non-coding ribonucleic acids (lncRNAs) are crucial in the progress of hepatocellular carcinoma (HCC).
To classify a long non-coding RNA, i.e., lncRNA W5, and to determine the clinical significance and potential roles of lncRNA W5 in HCC.
The results showed that lncRNA W5 expression was significantly downregulated in HCC cell lines and tissues. Analysis of the association between lncRNA W5 expression levels and clinicopathological features suggested that low lncRNA W5 expression was related to large tumor size (P < 0.01), poor histological grade (P < 0.05) and serious portal vein tumor thrombosis (P < 0.05). Furthermore, Kaplan-Meier survival analysis showed that low expression of lncRNA W5 predicts poor overall survival (P = 0.016).
Gain-of-loss function experiments, including cell counting kit8 assays, colony formation assays, and transwell assays, were performed in vitro to investigate the biological roles of lncRNA W5. In vitro experiments showed that ectopic overexpression of lncRNA W5 suppressed HCC cell proliferation, migration and invasion; conversely, silencing of lncRNA W5 promoted cell proliferation, migration and invasion. In addition, acting as a tumor suppressor gene in HCC, lncRNA W5 inhibited the growth of HCC xenograft tumors in vivo.
These results showed that lncRNA W5 is down-regulated in HCC, and it may suppress HCC progression and predict poor clinical outcomes in patients with HCC. LncRNA W5 may serve as a potential HCC prognostic biomarker in addition to a therapeutic target.
Core Tip: Our results showed that the expression of long non-coding ribonucleic acid (lncRNA) W5 was considerably reduced in hepatocellular carcinoma (HCC) tissues, which suppressed proliferation, migration and invasion of tumor cells in vitro. It was also shown that low expression of lncRNA W5 correlated with tumor progression and poor prognosis. Furthermore, manipulation of lncRNA W5 expression affected the biological behavior of HCC. These results suggest that lncRNA W5 may serve as a tumor suppressor in the development and progression of HCC, and has the potential to be a diagnostic and therapeutic target in the clinical management of HCC.