Overexpression of MUC13, a Poor Prognostic Predictor, Promotes Cell Growth by Activating Wnt Signaling in Hepatocellular Carcinoma.

Recently RNA sequencing revealed high mucin 13 (MUC13) expression in hepatocellular carcinoma (HCC) tissues. To understand the clinicopathologic significance of MUC13 in HCC, quantitative PCR and immunohistochemistry were used to detect its expression in paired tumor tissues and nontumor tissues. The oncoprotein role of MUC13 was determined by in vitro and in vivo assays. Overexpression of MUC13 was detected in 74 of 168 primary HCC cases (44%) and was significantly associated with tumor size (P = 0.027), stage (P = 0.006), encapsulation (P = 0.044), venous invasion (P = 0.024), and poor outcome (P = 0.004). Functional studies demonstrated MUC13 had strong oncogenic activity by promoting cell growth, colony formation, cell migration, and tumor formation in nude mice. The pro-oncogenic effect of MUC13 were effectively inhibited by RNA interference. MUC13 promoted cellular G1/S phase transition by activating Wnt signaling. Mechanistically, MUC13 bound to β-catenin and increased its phosphorylation at Ser552 and Ser675 sites, which subsequently promoted nuclear translocation of β-catenin and up-regulation of its downstream target genes Axin2, c-Myc, and CyclinD1. Knockdown of AKT with shRNA in MUC13-overexpressing cells nullified the elevated phosphorylation of β-catenin by MUC13. In clinical HCC samples, nuclear translocation of β-catenin was significantly associated with MUC13 overexpression (P = 0.001). Overexpression of MUC13 plays a critical role in the development and progression of HCC by activating Wnt signaling.

Dai Y ，Liu L ，Zeng T ，Liang JZ ，Song Y ，Chen K ，Li Y ，Chen L ，Zhu YH ，Li J ，Li Y ，Xie D ，Yuan YF ，Guan XY ... -  《-》

NLRC5 regulates cell proliferation, migration and invasion in hepatocellular carcinoma by targeting the Wnt/β-catenin signaling pathway.

NLRC5, the largest member of nucleotide-binding and oligomerization domain (NOD)-like receptor (NLR) family, has been reported to regulate immune responses and is associated with chronic inflammatory diseases. However, the biological function of NLRC5 in hepatocellular carcinoma (HCC) has not yet been well demonstrated. In this study, the role of NLRC5 in hepatocellular carcinoma cell proliferation, migration and invasion capacities was evaluated by using MTT, flow cytometry, wound healing, transwell assay, and tumor formation assay in nude mice. Western blot analysis and qPCR assay were performed to assess NLRC5 interacting with the activation of Wnt/β-catenin signaling pathway. Here, we demonstrate that NLRC5 was highly expressed in HCC. Knockdown of NLRC5 significantly inhibited cell proliferation, migration, invasion and the tumor formation in nude mice, and arrested the cell cycle at G0/G1 phase. Furthermore, overexpression of NLRC5 promoted the proliferation, migration and invasion of HCC cells in vitro. Interestingly, we found that up-regulation of NLRC5 not only positively correlates with the increase of β-catenin but also coordinates the activation of downstream Wnt/β-catenin signaling pathway. Thus, our findings suggest that NLRC5 may play an important role in progression of HCC and provide a potential therapeutic value in this tumor.

Peng YY ，He YH ，Chen C ，Xu T ，Li L ，Ni MM ，Meng XM ，Huang C ，Li J ... -  《-》

GCNT3 regulated MUC13 to promote the development of hepatocellular carcinoma through the GSK3β/β-catenin pathway.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide. Extensive research is currently directed at identifying novel targets for its diagnosis and treatment. We investigated the biological functions and clinical significance of mucin-type N-acetylglucosaminyltransferase 3 (GCNT3) in HCC. Variations in the mRNA expression of GCNT3 were examined in normal and HCC tissues. Cell function assays and animal models characterized the effects of GCNT3 on the proliferation, invasion, and migration abilities of HCC cells. Western blot and immunofluorescence analyses were performed to explore further the specific mechanisms whereby GCNT3 affects HCC progression. There is a strong correlation between GCNT3 overexpression and tumor formation and metastasis in vivo and in vitro. GCNT3 acted as a regulator of the synthesis of mucin-type O-glycans by interacting with mucin 13 (MUC13) to regulate its expression levels, activating the GSK3β/β-catenin signaling pathway. The activation of GSK3β/β-catenin signaling by GCNT3 was mitigated by MUC13 knockdown. In clinical HCC specimens, GCNT3 expression was upregulated in HCC tissues compared to non-tumor tissues. Further, there was a significant correlation between high GCNT3 expression and poor patient survival. GCNT3 regulated tumor progression in HCC through the MUC13/GSK3-β/β-catenin signaling pathway.

Kang Q ，Tingting W ，Bingzi D ，Hao Z ，Yuwei X ，Chuandong S ，Chengzhan Z ... -  《-》

HEG1 indicates poor prognosis and promotes hepatocellular carcinoma invasion, metastasis, and EMT by activating Wnt/β-catenin signaling.

Heart development protein with EGF-like domains 1 (HEG1) plays critical roles in embryo development and angiogenesis, which are closely related to tumor progression. However, the role of HEG1 in hepatocellular carcinoma (HCC) remains unknown. In the present study, we explored the clinical significance, biological function and regulatory mechanisms of HEG1 in HCC and found that HEG1 is significantly up-regulated in HCC cell lines and primary tumor samples. Additionally, high HEG1 expression is correlated with aggressive clinicopathological features. Patients with high HEG1 expression had shorter overall survival (OS) and disease-free survival (DFS) than those with low HEG1 expression, which indicated that HEG1 is an independent factor for poor prognosis. Lentivirus-mediated HEG1 overexpression significantly promotes HCC cell migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and promotes intrahepatic metastasis, lung metastasis and EMT in vivo Opposing results are observed when HEG1 is silenced. Mechanistically, HEG1 promotes β-catenin expression and maintains its stability, leading to intracellular β-catenin accumulation, β-catenin nuclear translocation and Wnt signaling activation. Loss- and gain-of-function assays further confirmed that β-catenin is essential for HEG1-mediated promotion of HCC invasion, metastasis and EMT. In conclusion, HEG1 indicates poor prognosis; plays important roles in HCC invasion, metastasis and EMT by activating Wnt/β-catenin signaling; and can serve as a potentially valuable prognostic biomarker and therapeutic target for HCC.

Zhao YR ，Wang JL ，Xu C ，Li YM ，Sun B ，Yang LY ... -  《-》

Proline-rich protein 11 silencing inhibits hepatocellular carcinoma growth and epithelial-mesenchymal transition through β-catenin signaling.

Proline-rich protein 11 (PRR11) has been shown to play an critical roles in the development of cancer. However, the clinical significance and the biological role of PRR11 in hepatocellular carcinoma (HCC) remains unknown. The present study aimed to investigate the expression pattern, prognostic value and the biological role of PRR11 in HCC. PRR11 expression in 80 HCC surgical specimens was examined, and its clinical significance was analyzed. The role of PRR11 in cell proliferation, colony formation, migration and invasion were also determined. The results showed that PRR11 mRNA was significantly up-regulated in 56.25% (45/80) HCC from that in matched adjacent non-tumor tissues. High PRR11 was correlated with tumor size (P = 0.01) and TNM stage (P = 0.006). Patients with higher PRR11 expression had poor overall survival time (P < 0.001). Furthermore, PRR11 silencing obviously inhibited cell proliferation, colony formation, as well as cell migration and invasion of HCC cell lines in vitro. Mechanistically, knockdown of PRR11 significantly decreased the expression of β-catenin, cyclinD1, c-myc and N-cadherin in HCC cell lines. Additionally, the inhibitory effects of PRR11 silencing on cell migration was significantly enhanced by β-catenin inhibition. PRRl1 mRNA expression was found positively correlated with β-catenin (R = 0.5472, P ˂ 0.0001), c-myc (R = 0.5527, P ˂ 0.0001) and cyclinD1 (R = 0.3948, P = 0.0003) in HCC tissues. Collectively, our data demonstrate that PRR11 plays an oncogenic role in HCC progression, through activating the Wnt/β-catenin signaling pathway, and may represent a valuable prognostic marker and therapeutic target for HCC.

Qiao W ，Wang H ，Zhang X ，Luo K ... -  《-》