Role of Wnt5a in suppressing invasiveness of hepatocellular carcinoma via epithelial-mesenchymal transition

Wnt Signaling in Hepatocellular Carcinoma: Biological Mechanisms and Therapeutic Opportunities

Hepatocellular carcinoma (HCC), characterized by significant morbidity and mortality rates, poses a substantial threat to human health. The expression of ligands and receptors within the classical and non-classical Wnt signaling pathways plays an important role in HCC. The Wnt signaling pathway is essential for regulating multiple biological processes in HCC, including proliferation, invasion, migration, tumor microenvironment modulation, epithelial-mesenchymal transition (EMT), stem cell characteristics, and autophagy. Molecular agents that specifically target the Wnt signaling pathway have demonstrated significant potential for the treatment of HCC. However, the precise mechanism by which the Wnt signaling pathway interacts with HCC remains unclear. In this paper, we review the alteration of the Wnt signaling pathway in HCC, the mechanism of Wnt pathway action in HCC, and molecular agents targeting the Wnt pathway. This paper provides a theoretical foundation for identifying molecular agents targeting the Wnt pathway in hepatocellular carcinoma.

Multiomics Analysis of Molecules Associated with Cancer in Mesenchymal-Stem-Cell-(MSC)-Derived Exosome-Treated Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC) is the most common form of liver cancer in humans, with an increasing incidence worldwide. The current study aimed to explore the molecular mechanisms that inhibit the proliferation of HepG2 cells, a hepatoblastoma-derived cell line. MSC-derived exosomes (UC-MSCs) were prepared with a median particle size (N50) of 135.8 nm. Concentrations of UC-MSCs ranging from 10 μg/mL to 1000 μg/mL were applied to HepG2 cell cultures and compared to untreated and anticancer drug-treated HepG2 cells. A combined approach was employed, integrating a proteomic analysis of UC-MSCs, metabolomic analysis of HepG2 cells, and transcriptomic profiling of HepG2 cells to decipher the inhibitory mechanisms of UC-MSC exosomes on HepG2 cell growth. Treatment with a high concentration of UC-MSCs led to a notable reduction in HepG2 cell viability, with survival decreasing by 65%. A proteomic analysis of UC-MSCs revealed enriched degranulation processes in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, in addition to the known exosomal pathways. Transcriptomic profiling showed distinct changes in the expression of genes related to hepatocellular diseases in UC-MSC-treated HepG2 cells, contrasting with changes observed in HepG2 cells treated with the chemotherapeutic agent doxorubicin (DOX). Combined with a metabolomic analysis, the detailed GO and KEGG pathway analyses indicated that pathways associated with neutrophil extracellular trap formation played a critical role in mediating protein degradation and suppressing central carbon metabolism in cancer cells. Our results revealed that the UC-MSC treatment mimicked molecular mechanisms similar to those involved in neutrophil extracellular trap formation, exhibiting effects on HepG2 cell growth suppression that differed from those of chemical cancer drugs. Notably, the UC-MSC treatment demonstrated that protein degradation in HepG2 cells was regulated through canonical signaling pathways activated by bacterial peptides in neutrophils. This research has provided valuable insights into the potential of MSC-derived exosomes as a therapeutic approach for cancer treatment in the future.

WNT/β-catenin signaling in hepatocellular carcinoma: The aberrant activation, pathogenic roles, and therapeutic opportunities

Hepatocellular carcinoma (HCC) is a liver cancer, highly heterogeneous both at the histopathological and molecular levels. It arises from hepatocytes as the result of the accumulation of numerous genomic alterations in various signaling pathways, including canonical WNT/β-catenin, AKT/mTOR, MAPK pathways as well as signaling associated with telomere maintenance, p53/cell cycle regulation, epigenetic modifiers, and oxidative stress. The role of WNT/β-catenin signaling in liver homeostasis and regeneration is well established, whereas in development and progression of HCC is extensively studied. Herein, we review recent advances in our understanding of how WNT/β-catenin signaling facilitates the HCC development, acquisition of stemness features, metastasis, and resistance to treatment. We outline genetic and epigenetic alterations that lead to activated WNT/β-catenin signaling in HCC. We discuss the pivotal roles of CTNNB1 mutations, aberrantly expressed non-coding RNAs and complexity of crosstalk between WNT/β-catenin signaling and other signaling pathways as challenging or advantageous aspects of therapy development and molecular stratification of HCC patients for treatment.

Expression of Wnt5a and ROR2, Components of the Noncanonical Wnt-Signaling Pathway, is Associated with Tumor Differentiation in Hepatocellular Carcinoma

BACKGROUND

Wnt5a is the key ligand of the noncanonical Wnt pathway, and receptor tyrosine kinase-like orphan receptor 2 (ROR2) is a receptor associated with Wnt5a. The association between the noncanonical Wnt-signaling pathway and carcinogenesis in hepatocellular carcinoma (HCC) is unclear. This study investigated the significance of ROR2 expression in HCC.

METHODS

The study examined ROR2 expression in liver cancer cell lines. Immunohistochemical staining of ROR2 was performed on 243 resected HCC specimens. The study investigated ROR2 expression and its association with clinicopathologic factors and prognosis.

RESULTS

Findings showed that ROR2 was expressed in well-differentiated Huh7 and HepG2 cells, but not in poorly differentiated HLE and HLF cells. Expression of ROR2 was positive in 147 (60.5%) and negative in 96 (39.5%) HCC specimens. A significant association was shown between ROR2 negativity and high alpha-fetoprotein (AFP) level (P = 0.006), poor differentiation (P = 0.015), and Wnt5a negativity (P = 0.024). The 5-year overall survival (OS) rate for the ROR2-negative group (64.2 %) tended to be worse than for the ROR2-positive group (73.8%), but the difference was not significant (P = 0.312). The 5-year OS rate was 78.7% for the ROR2+Wnt5a+ group, 71.3 % for the ROR2+Wnt5a- group, 80.8% for the ROR2-Wnt5a+ group, and 60.5 % for the ROR2-Wnt5a- group. The OS in the ROR2-Wnt5a- group was significantly poorer than in the ROR2+Wnt5a+ group (P = 0.030). The multivariate analysis showed that Wnt5a-ROR2- was an independent prognostic factor (hazard ratio, 2.058; 95% confidence interval, 1.013-4.180; P = 0.045).

CONCLUSIONS

The combination of ROR2 and Wnt5a may be a prognostic indicator for HCC. The Wnt5a/ROR2 signal pathway may be involved in the differentiation of HCC. This pathway may be a new therapeutic target for HCC.

LGR5 Expression Predicting Poor Prognosis Is Negatively Correlated with WNT5A in Colon Cancer

WNT/β-catenin signaling is essential for colon cancer development and progression. WNT5A (ligand of non-canonical WNT signaling) and its mimicking peptide Foxy5 impair β-catenin signaling in colon cancer cells via unknown mechanisms. Therefore, we investigated whether and how WNT5A signaling affects two promoters of β-catenin signaling: the LGR5 receptor and its ligand RSPO3, as well as β-catenin activity and its target gene VEGFA. Protein and gene expression in colon cancer cohorts were analyzed by immunohistochemistry and qRT-PCR, respectively. Three colon cancer cell lines were used for in vitro and one cell line for in vivo experiments and results were analyzed by Western blotting, RT-PCR, clonogenic and sphere formation assays, immunofluorescence, and immunohistochemistry. Expression of WNT5A (a tumor suppressor) negatively correlated with that of LGR5/RSPO3 (tumor promoters) in colon cancer cohorts. Experimentally, WNT5A signaling suppressed β-catenin activity, LGR5, RSPO3, and VEGFA expression, and colony and spheroid formations. Since β-catenin signaling promotes colon cancer stemness, we explored how WNT5A expression is related to that of the cancer stem cell marker DCLK1. DCLK1 expression was negatively correlated with WNT5A expression in colon cancer cohorts and was experimentally reduced by WNT5A signaling. Thus, WNT5A and Foxy5 decrease LGR5/RSPO3 expression and β-catenin activity. This inhibits stemness and VEGFA expression, suggesting novel treatment strategies for the drug candidate Foxy5 in the handling of colon cancer patients.

Recent Advances in Systemic Therapies for Advanced Hepatocellular Carcinoma

Purpose of Review

This paper aims to summarize the data of recently completed and key ongoing clinical trials of systemic agents for advanced hepatocellular carcinoma (aHCC). In particular, the review focuses on ongoing checkpoint inhibitor combination trials and promising studies combining tyrosine kinase inhibitors with checkpoint inhibitors.

Recent Findings

The recently approved combination of atezolizumab and bevacizumab based on the IMbrave150 trial has shown the most potential with the highest overall survival of any systemic agent in HCC to date, surpassing sorafenib. Despite COVID-19 delays, other promising trials that involve combining VEGF-directed therapy and checkpoint inhibition, cancer vaccines, phosphatidylserine, YIV-906, and oncolytic and immunotherapeutic vaccinia virus are actively recruiting patients.

Summary

After almost a 10-year dormancy, the list of potential systemic treatment options for aHCC is growing rapidly. Given the promising data from the IMbrave150 trial, the combination of atezolizumab and bevacizumab is now the new first-line therapy. We discuss the change in landscape, the new second- and third-line systemic treatments in aHCC, and the ongoing clinical trials for newer agents including combination therapies.

Targeting Oncogenic WNT Signalling with WNT Signalling-Derived Peptides

WNT signalling is known to be a crucial regulator of embryonic development and tissue homeostasis. Aberrant expression of WNT signalling elements or their mutations has been implicated in carcinogenesis and/or the progression of several different cancer types. Investigations of how WNT signalling affects carcinogenesis and cancer progression have revealed that it has essential roles in the regulation of proliferation, apoptosis, and cancer stemness and in angiogenesis and metastasis. Consequently, WNT-targeted therapy has gained much attention and has resulted in the development of several small molecules, the majority of which act as inhibitors of different WNT signalling events. However, although numerous inhibitory WNT signalling drug candidates have been included in clinical trials, no significant breakthroughs have been made. This could possibly be due to problems with inefficient binding to the target, compensatory signalling mechanisms and toxicity towards normal cells. Therapeutic peptides targeting WNT signalling in cancer cells have been developed as an alternative approach, with the hope that they might overcome the limitations reported for small WNT inhibitory molecules. In this chapter, we describe recent developments made in the design and characterization of WNT signalling-derived peptides aiming at their use as alternative cancer therapeutics and/or combined adjuvant therapy to conventional therapies.