LncRNA SNHG5 promotes the proliferation and cancer stem cell-like properties of HCC by regulating UPF1 and Wnt-signaling pathway

The role of long noncoding RNA (lncRNAs) had been demonstrated in different types of cancer, including hepatocellular carcinoma. This study was intended to investigate the role of lncRNA small nucleolar RNA host gene 5 (SNHG5) in HCC proliferation and the liver CSC-like properties. Through functional experiments, we determined that knockdown of SNHG5 repressed HCC cell proliferation and CSC-like properties, while over-expression of SNHG5 promoted cell growth. At the same time, CSC markers (CD44, CD133, and ALDH1) and related transcription factors (OCT4, SOX2, and NANOG) were downregulated when SNHG5 was knocked down. Mechanically, RNA immunoprecipitation (RIP) and RNA pulldown assay showed that SNHG5 regulated the proliferation and CSC-like properties of HCC by binding UPF1. Further investigations showed that expression of critical components of Wnt/β-catenin pathway (β-catenin, TCF4, c-myc, cyclinD1, and c-Jun) were upregulated with depletion of UPF1 in liver CSCs, which were downregulated with depletion of SNHG5. After use of the inhibitor of Wnt/β-catenin pathway, the formation of liver CSCs sphere decreased. Taken together, SNHG5 plays a critical role to promote HCC cell proliferation and cancer stem cell-like properties via UPF1 and Wnt/β-catenin pathway.