Beta-catenin signaling, liver regeneration and hepatocellular cancer: sorting the good from the bad

Role of circular RNAs in preeclampsia (Review)

Preeclampsia (PE) is a hypertensive disorder of pregnancy characterized by new-onset hypertension and proteinuria after 20 weeks of gestation, which affects 3-8% of pregnant individuals worldwide each year. Prevention, diagnosis and treatment of PE are some of the most important problems faced by obstetrics. There is growing evidence that circular RNAs (circRNAs) are involved in the pathogenesis of PE. The present review summarizes the research progress of circRNAs and then describes the expression patterns of circRNAs in PE and their functional mechanisms affecting PE development. The role of circRNAs as biomarkers for the diagnosis of PE, and the research status of circRNAs in PE are summarized in the hope of finding novel strategies for the prevention and treatment of PE.

Retinoic acid generates a beneficial microenvironment for liver progenitor cell activation in acute liver failure

BACKGROUND

When massive necrosis occurs in acute liver failure (ALF), rapid expansion of HSCs called liver progenitor cells (LPCs) in a process called ductular reaction is required for survival. The underlying mechanisms governing this process are not entirely known to date. In ALF, high levels of retinoic acid (RA), a molecule known for its pleiotropic roles in embryonic development, are secreted by activated HSCs. We hypothesized that RA plays a key role in ductular reaction during ALF.

METHODS

RNAseq was performed to identify molecular signaling pathways affected by all-trans retinoid acid (atRA) treatment in HepaRG LPCs. Functional assays were performed in HepaRG cells treated with atRA or cocultured with LX-2 cells and in the liver tissue of patients suffering from ALF.

RESULTS

Under ALF conditions, activated HSCs secreted RA, inducing RARα nuclear translocation in LPCs. RNAseq data and investigations in HepaRG cells revealed that atRA treatment activated the WNT-β-Catenin pathway, enhanced stemness genes (SOX9, AFP, and others), increased energy storage, and elevated the expression of ATP-binding cassette transporters in a RARα nuclear translocation-dependent manner. Further, atRA treatment-induced pathways were confirmed in a coculture system of HepaRG with LX-2 cells. Patients suffering from ALF who displayed RARα nuclear translocation in the LPCs had significantly better MELD scores than those without.

CONCLUSIONS

During ALF, RA secreted by activated HSCs promotes LPC activation, a prerequisite for subsequent LPC-mediated liver regeneration.

Liver regeneration after injury: Mechanisms, cellular interactions and therapeutic innovations

The liver possesses a distinctive capacity for regeneration within the human body. Under normal circumstances, liver cells replicate themselves to maintain liver function. Compensatory replication of healthy hepatocytes is sufficient for the regeneration after acute liver injuries. In the late stage of chronic liver damage, a large number of hepatocytes die and hepatocyte replication is blocked. Liver regeneration has more complex mechanisms, such as the transdifferentiation between cell types or hepatic progenitor cells mediated. Dysregulation of liver regeneration causes severe chronic liver disease. Gaining a more comprehensive understanding of liver regeneration mechanisms would facilitate the advancement of efficient therapeutic approaches. This review provides an overview of the signalling pathways linked to different aspects of liver regeneration in various liver diseases. Moreover, new knowledge on cellular interactions during the regenerative process is also presented. Finally, this paper explores the potential applications of new technologies, such as nanotechnology, stem cell transplantation and organoids, in liver regeneration after injury, offering fresh perspectives on treating liver disease.

Dihydroquercetin improves the proliferation of porcine intestinal epithelial cells via the Wnt/β-catenin pathway

Dihydroquercetin (DHQ), also known as Taxifolin (TA), is a flavanonol with various biological activities, such as anticancer, anti-inflammatory, and antioxidative properties. It has been found to effectively increase the viability of porcine intestinal epithelial cells (IPEC-J2). However, the precise mechanism by which DHQ increases the proliferation of IPEC-J2 cells is not entirely understood. This study aimed to explore the potential pathways through which DHQ encourages the proliferation of IPEC-J2 cells. The findings indicated that DHQ significantly improved the protein expression of tight junction proteins (ZO-1, Occludin, and Claudin1) and a molecular biomarker of proliferation (PCNA) in IPEC-J2 cells. Furthermore, DHQ was found to increase the Wnt/β-catenin pathway-associated β-catenin, c-Myc, and cyclin D1 mRNA expression, and promote the protein expression of β-catenin and TCF4. To confirm the involvement of the Wnt/β-catenin signaling pathway in the DHQ-promoted proliferation of IPEC-J2 cells, the inhibitor LF3, which targets β-catenin/TCF4 interaction, was used. It was found that LF3 inhibited the protein expressions upregulated by DHQ and blocked the promotion of cell proliferation. These results indicate that DHQ positively regulates IPEC-J2 cell proliferation through the Wnt/β-catenin pathway, providing constructive insights into the role of DHQ in regulating intestine development.

3D organoid cultivation improves the maturation and functional differentiation of cholangiocytes from human pluripotent stem cells

Idiopathic cholangiopathies are diseases that affect cholangiocytes, and they have unknown etiologies. Currently, orthotopic liver transplantation is the only treatment available for end-stage liver disease. Limited access to the bile duct makes it difficult to model cholangiocyte diseases. In this study, by mimicking the embryonic development of cholangiocytes and using a robust, feeder- and serum-free protocol, we first demonstrate the generation of unique functional 3D organoids consisting of small and large cholangiocytes derived from human pluripotent stem cells (PSCs), as opposed to traditional 2D culture systems. At day 28 of differentiation, the human PSC-derived cholangiocytes expressed markers of mature cholangiocytes, such as CK7, CK19, and cystic fibrosis transmembrane conductance regulator (CFTR). Compared with the 2D culture system-generated cholangiocytes, the 3D cholangiocyte organoids (COs) showed higher expression of the region-specific markers of intrahepatic cholangiocytes YAP1 and JAG1 and extrahepatic cholangiocytes AQP1 and MUC1. Furthermore, the COs had small-large tube-like structures and functional assays revealed that they exhibited characteristics of mature cholangiocytes, such as multidrug resistance protein 1 transporter function and CFTR channel activity. In addition to the extracellular matrix supports, the epidermal growth factor receptor (EGFR)-mediated signaling regulation might be involved in this cholangiocyte maturation and differentiation. These results indicated the successful generation of intrahepatic and extrahepatic cholangiocytes by using our 3D organoid protocol. The results highlight the advantages of our 3D culture system over the 2D culture system in promoting the functional differentiation and maturation of cholangiocytes. In summary, in advance of the previous works, our study provides a possible concept of small-large cholangiocyte transdifferentiation of human PSCs under cost-effective 3D culture conditions. The study findings have implications for the development of effective cell-based therapy using COs for patients with cholangiopathies.

NLRP3 deficiency protects against acetaminophen‑induced liver injury by inhibiting hepatocyte pyroptosis

Acetaminophen (APAP) overdose is the primary cause of drug‑induced acute liver failure in numerous Western countries. NLR family pyrin domain containing 3 (NLRP3) inflammasome activation serves a pivotal role in the pathogenesis of various forms of acute liver injury. However, the cellular source for NLRP3 induction and its involvement during APAP‑induced hepatotoxicity have not been thoroughly investigated. In the present study, hematoxylin and eosin staining was performed to assess histopathological changes of liver tissue. Immunohistochemistry staining(NLRP3, Caspase‑1, IL‑1β, GSDMD and Caspase‑3), western blotting (NLRP3, Caspase‑1, IL‑1β, GSDMD and Caspase‑3) and RT‑qPCR (NLRP3, Caspase‑1 and IL‑1β) were performed to assess the expression of NLRP3/GSDMD signaling pathway. TUNEL staining was performed to assess apoptosis of liver tissue. The serum expression levels of inflammatory factors (IL‑6, IL‑18, IL‑1β and TNF‑α) were assessed using ELISA and inflammation of liver tissue was assessed using immunohistochemistry (Ly6G and CD68) and RT‑qPCR (TNF‑α, Il‑6, Mcp‑1, Cxcl‑1, Cxcl‑2). A Cell Counting Kit‑8 was performed to assess cell viability and apoptosis. Protein and gene expression were analyzed by western blotting (PCNA, CCND1) and RT‑qPCR (CyclinA2, CyclinD1 and CyclinE1). Through investigation of an APAP‑induced acute liver injury model (AILI), the present study demonstrated that APAP overdose induced activation of NLRP3 and cleavage of gasdermin D (GSDMD) in hepatocytes, both in vivo and in vitro. Additionally, mice with hepatocyte‑specific knockout of Nlrp3 exhibited reduced liver injury and lower mortality following APAP intervention, accompanied by decreased infiltration of inflammatory cells and attenuated inflammatory response. Furthermore, pharmacological blockade of NLRP3/GSDMD signaling using MCC950 or disulfiram significantly ameliorated liver injury and reduced hepatocyte death. Notably, hepatocyte Nlrp3 deficiency promoted liver recovery by enhancing hepatocyte proliferation. Collectively, the present study demonstrated that inhibition of the NLRP3 inflammasome protects against APAP‑induced acute liver injury by reducing hepatocyte pyroptosis and suggests that targeting NLRP3 may hold therapeutic potential for treating AILI.

Exploring the oncogenic and tumor-suppressive roles of Circ-ADAM9 in cancer

Circular RNAs (circRNAs) constitute a recently identified category of closed continuous loop RNA transcripts, serving as a subset of competing endogenous RNAs (ceRNAs) with the capacity to modulate genes by acting as microRNA sponges. In the context of cancer growth, numerous investigations have explored the potential functions of circRNAs, revealing their diverse functions either as oncogenes, promoting cancer progression, or as tumor suppressors, mitigating disease development. Among these, circRNA ADAM9 (Circ-ADAM9) is now recognized as an important player in a variety of mechanisms, both physiological and pathological, especially in cancer. The aberrant expression of Circ-ADAM9 has been observed across multiple human malignancies, implying a significant involvement in tumorigenesis. This comprehensive review aims to synthesize recent findings elucidating the function of Circ-ADAM9 in many malignancies. Additionally, the review explores the possibility of Circ-ADAM9 as a valuable biomarker, offering insights into its prognostic, diagnostic, and therapeutic implications. By summarizing the latest discoveries in this field, the review contributes to our understanding of the multifaceted contribution of Circ-ADAM9 in tumor biology and its potential applications in clinical settings.

Hepatocellular carcinoma: signaling pathways, targeted therapy, and immunotherapy

Hepatocellular carcinoma (HCC) is the most common primary liver cancer with a high mortality rate. It is regarded as a significant public health issue because of its complicated pathophysiology, high metastasis, and recurrence rates. There are no obvious symptoms in the early stage of HCC, which often leads to delays in diagnosis. Traditional treatment methods such as surgical resection, radiotherapy, chemotherapy, and interventional therapies have limited therapeutic effects for HCC patients with recurrence or metastasis. With the development of molecular biology and immunology, molecular signaling pathways and immune checkpoint were identified as the main mechanism of HCC progression. Targeting these molecules has become a new direction for the treatment of HCC. At present, the combination of targeted drugs and immune checkpoint inhibitors is the first choice for advanced HCC patients. In this review, we mainly focus on the cutting-edge research of signaling pathways and corresponding targeted therapy and immunotherapy in HCC. It is of great significance to comprehensively understand the pathogenesis of HCC, search for potential therapeutic targets, and optimize the treatment strategies of HCC.

Wnt-β-catenin in hepatobiliary homeostasis, injury, and repair

Wnt-β-catenin signaling has emerged as an important regulatory pathway in the liver, playing key roles in zonation and mediating contextual hepatobiliary repair after injuries. In this review, we will address the major advances in understanding the role of Wnt signaling in hepatic zonation, regeneration, and cholestasis-induced injury. We will also touch on some important unanswered questions and discuss the relevance of modulating the pathway to provide therapies for complex liver pathologies that remain a continued unmet clinical need.

Wnt/beta-catenin signaling and its modulators in nonalcoholic fatty liver diseases

Nonalcoholic fatty liver disease (NAFLD) is a global health concern associated with significant morbidity and mortality. NAFLD is a spectrum of diseases originating from simple steatosis, progressing through nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis that may lead to hepatocellular carcinoma (HCC). The pathogenesis of NAFLD is mediated by the triglyceride accumulation followed by proinflammatory cytokines expression leading to inflammation, oxidative stress, and mitochondrial dysfunction denoted as "two-hit hypothesis", advancing with a "third hit" of insufficient hepatocyte proliferation, leading to the increase in hepatic progenitor cells contributing to fibrosis and HCC. Wnt/β-catenin signaling is responsible for normal liver development, regeneration, hepatic metabolic zonation, ammonia and drug detoxification, hepatobiliary development, etc., maintaining the overall liver homeostasis. The key regulators of canonical Wnt signaling such as LRP6, Wnt1, Wnt3a, β-catenin, GSK-3β, and APC are abnormally regulated in NAFLD. Many experimental studies have shown the aberrated Wnt/β-catenin signaling during the NAFLD progression and NASH to hepatic fibrosis and HCC. Therefore, in this review, we have emphasized the role of Wnt/β-catenin signaling and its modulators that can potentially aid in the inhibition of NAFLD.

A spotlight on the interplay between Wnt/β-catenin signaling and circular RNAs in hepatocellular carcinoma progression

Hepatocellular carcinoma (HCC) is one of the deadliest cancers due to multifocal development and distant metastasis resulting from late diagnosis. Consequently, new approaches to HCC diagnosis and treatment are required to reduce mortality rates. A large body of evidence suggests that non-coding RNAs (ncRNAs) are important in cancer initiation and progression. Cancer cells release many of these ncRNAs into the blood or urine, enabling their use as a diagnostic tool. Circular RNAs (CircRNAs) are as a members of the ncRNAs that regulate cancer cell expansion, migration, metastasis, and chemoresistance through different mechanisms such as the Wnt/β-catenin Signaling pathway. The Wnt/β-catenin pathway plays prominent roles in several biological processes including organogenesis, stem cell regeneration, and cell survival. Aberrant signaling of both pathways mentioned above could affect the progression and metastasis of many cancers, including HCC. Based on several studies investigated in the current review, circRNAs have an effect on HCC formation and progression by sponging miRNAs and RNA-binding proteins (RBPs) and regulating the Wnt/β-catenin signaling pathway. Therefore, circRNAs/miRNAs or RBPs/Wnt/β-catenin signaling pathway could be considered promising prognostic and therapeutic targets in HCC.

The endocannabinoid system promotes hepatocyte progenitor cell proliferation and maturation by modulating cellular energetics

The proliferation and differentiation of hepatic progenitor cells (HPCs) drive the homeostatic renewal of the liver under diverse conditions. Liver regeneration is associated with an increase in Axin2⁺Cnr1⁺ HPCs, along with a marked increase in the levels of the endocannabinoid anandamide (AEA). But the molecular mechanism linking AEA signaling to HPC proliferation and/or differentiation has not been explored. Here, we show that in vitro exposure of HPCs to AEA triggers both cell cycling and differentiation along with increased expression of Cnr1, Krt19, and Axin2. Mechanistically, we found that AEA promotes the nuclear localization of the transcription factor β-catenin, with subsequent induction of its downstream targets. Systemic analyses of cells after CRISPR-mediated knockout of the β-catenin-regulated transcriptome revealed that AEA modulates β-catenin-dependent cell cycling and differentiation, as well as interleukin pathways. Further, we found that AEA promotes OXPHOS in HPCs when amino acids and glucose are readily available as substrates, but AEA inhibits it when the cells rely primarily on fatty acid oxidation. Thus, the endocannabinoid system promotes hepatocyte renewal and maturation by stimulating the proliferation of Axin2⁺Cnr1⁺ HPCs via the β-catenin pathways while modulating the metabolic activity of their precursor cells.

Transcriptional activation of CSTB gene expression by transcription factor Sp3

CSTB has been reported to be associated with the pathogenesis of many malignant tumors, especially hepatocellular carcinoma (HCC). However, how the expression of this gene is regulated is largely unknown. We initially cloned and analyzed the promoter region of the CSTB gene by luciferase assay and the Sp3 binding site (CCCCGCCCCGCG) was found in it. The results of electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) experiments verified that the transcription factor, Sp3 could bind to the " CCCCGCCCCGCG ″ site of the CSTB gene promoter. We showed that the overexpression of Sp3 significantly increased the endogenous mRNA and protein expression levels of CSTB, whereas knockdown of Sp3 decreased the mRNA and protein expression levels according to quantitative real-time PCR (qRT‒PCR) and western blotting. In conclusion, CSTB gene expression is closely regulated by transcription factor Sp3, which may be a potential mechanism for the dysregulation of CSTB expression in HCC.

Differences in tissue distribution ability of evodiamine and dehydroevodiamine are due to the dihedral angle of the molecule stereo-structure

Introduction: This researcher focused at the evodiamine and dehydroevodiamine tissue distribution and structure-pharmacokinetics (PK) relationship after intravenous injection in mice. Methods: Using a transmembrane transport experiment, the permeability of evodiamine and dehydroevodiamine on Caco-2 cells was evaluated. The tissue distribution and pharmacokinetics (PK) of evodiamine and dehydroevodiamine in mice were studied. To comprehend the connection between structure and tissue distribution, physicochemical property evaluations and molecular electrostatic potential (MEP) calculations were performed. Results: Dehydroevodiamine's Papp values in vitro were 10^-5 cm/s, whereas evodiamine's were 10^-6 cm/s. At a dose of 5 mg/kg, the brain concentration of dehydroevodiamine was 6.44 times more than that of evodiamine. By MEP or physicochemical measures, the permeability difference between evodiamine and dehydroevodiamine is unaffected. The dihedral angle of the stereo-structure appears to be the main cause of the difference in tissue distribution ability between evodiamine and dehydroevodiamine. Discussion: Dehydroevodiamine has a dihedral angle of 3.71° compared to 82.34° for evodiamine. Dehydroevodiamine can more easily pass through the phospholipid bilayer than evodiamine because it has a more planar stereo-structure. Dehydroevodiamine is therefore more likely to pass cross the blood-brain barrier and enter the brain in a tissue-specific manner.

Wnt/β-catenin targeting in liver carcinoma through nanotechnology-based drug repurposing: A review

Liver cancer is the fifth most widespread in the world, with a high fatality rate and poor prognosis.However,surgicalresction,thermal/radiofrequencyablation,chemo/radioembolization and pathway targeting to the cancer cells are all possible options for treating Liver Carcinoma. Unfortunately, once the tumour has developed and spread, diagnosis often occurs too late. The targeted therapy has demonstrated notable, albeit modest, efficacy in some patients with advanced HCC. This demonstrates the necessity of creating additional focused treatments and, in pursuit of this end, the need to find ever-more pathways as prospective targets. Despite the critical need, there are currently no Wnt signalling directed therapy on the research field, only a few methods have progressed beyond the early stage of clinical studies. In the present study, we report that repurposing of drug previously licensed for other diseases is one possible strategy inhibit malignant cell proliferation and renewal by removing individuals protein expression in the Wnt/β-catenin pathway. Particularly β-catenin complex is present in Liver cancer, where tumour necrosis factor is indispensable for the complex formation and β-catenin interactions are disrupted upon drug in nano-carrier through nanotechnology. This study findings not only highlight that repurposing drug could improve liver cancer treatment outcomes but also focused to character traits and functions of the Wnt signalling cascade's molecular targets and how they could be used to get anti-tumour results method to targeting Wnt/β-catenin in liver carcinoma.

Design, synthesis and evaluation of 4,7-disubstituted 8-methoxyquinazoline derivatives as potential cytotoxic agents targeting β-catenin/TCF4 signaling pathway

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Novel 4,7-disubstituted 8-methoxyquinazoline based derivativesdisrupting β-catenin/TCF4 interactions were synthesized.

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Cytotoxic potencies of these derivatives were found to be comparable with imatinib mesylate against constitutively activated β-catenin/TCF4 signaling cancer cells (IC₅₀ ranged from 5.64 ± 0.68 to 23.18 ±0.45 μM against HCT116 and HepG2 cells).

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Compound (18B) was found to be the most potent compound.

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Compound (18B) induced apoptosis and inhibited cell migration against HCT116 and HepG2 cells.

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Compound (18B) significantly downregulated β-catenin/TCF4 signaling pathway (reduced TOP-luciferase activity), β-catenin and TCF4 protein expression, and mRNA levels of c-MYC and Cyclin D1 (Wnt target genes) against HCT116 cells and showed cytotoxicity against primary human gallbladder cancer cells (IC₅₀ 8.50±1.44).

Overactivation of Wnt/β-catenin signaling by accumulated β-catenin in the nucleus has been shown to play a crucial role in the etiology of cancer. Interaction of β-catenin with Transcription factor 4 (TCF4) is a key step for the activation of Wnt genes in response to upstream signals of the Wnt/β-catenin pathway. Hence, down regulation of Wnt/β-catenin signaling or targeting downstream events by selective β-catenin/TCF4 protein–protein interaction inhibitors could be a potential therapeutic strategy against such cancers. In this study structure-based drug design approach was followed to design novel 4,7-disubstituted 8-methoxyquinazoline-based derivatives which could act as potential cytotoxic agents inhibiting the β-catenin/TCF4 protein–protein interactions. Fifteen compounds possessing 4,7-disubstituted 8-methoxyquinazoline scaffold were synthesized. Cytotoxic potential of the synthesised derivatives were determined against constitutively activated β-catenin/TCF4 signaling pathway cancer cells (HCT116 and HepG2) using the sulforhodamine B assay. The most potent compound (18B) was selected for detailed biological evaluation. Cell morphology, Hoechst 33342 and Annexin V/PI staining were used to detect apoptosis, while inhibition of cell migration was assessed by in vitro wound healing assay against HCT116 and HepG2 cells. Effect on β-catenin/TCF mediated transcriptional activity was assessed by TOPFlash/FOPFlash assay, TCF4 and β-catenin protein expression by immunocytofluorescence, and Wnt target genes (like c-MYC and Cyclin D1) mRNA levels by RT-PCR against HCT116 cells. Cytotoxic potency of the most potential compound (18B) against primary human gallbladder cancer cells was also evaluated. The derivatives showed interactions with active site residues of β-catenin and were capable of hindering the TCF4 binding, thereby disrupting β-catenin/TCF4 interactions. Cytotoxic potencies (IC₅₀) of these derivatives ranged from 5.64 ± 0.68 to 23.18 ± 0.45 μM against HCT116 and HepG2 cells respectively. Compound (18B), the most potent compound among the series, induced apoptosis and inhibited cell migration against HCT116 and HepG2 cells. Mechanistic studies indicated that compound (18B) downregulated β-catenin/TCF4 signaling pathway, β-catenin and TCF4 protein expression, and mRNA levels of c-MYC andCyclin D1 in HCT116 cells and showed cytotoxicity against primary human gallbladder cancer cells with IC₅₀ value of 8.50 ± 1.44 μM. Thus, novel 4,7-disubstituted 8-methoxyquinazoline derivatives were identified as potential cytotoxic agents with potencies comparable to that of imatinib mesylate. Compound (18B) represents a promising lead molecule as anticancer agent against colon, hepatocellular and gallbladder cancers targeting β-catenin/TCF4 signaling pathway.

Targeting Wnt/β-Catenin Pathways in Primary Liver Tumours: From Microenvironment Signaling to Therapeutic Agents

Primary liver cancers (PLCs) are steadily increasing in incidence and mortality in the world. They have a poor prognosis due to their silent nature, late discovery and resistance to common chemotherapy. At present, there are limited treatment alternatives, and the understanding of PLC molecular aspects is essential to develop more efficient drugs and therapeutic surgical and loco-regional strategies. A clear causal link with liver damage, inflammation, and regeneration has been found in the occurrence of PLC over the last few decades. Physiologically, Wingless/It (Wnt)-β-catenin signaling plays a key role in liver development, metabolic zonation and regeneration. Loss of functional homeostasis of this pathway appears to be a major driver of carcinogenesis in the liver parenchyma. In the hepatic microenvironment, molecular deregulations that exceed the Wnt signaling biological capacity can induce tumor initiation and progression. Indeed, somatic mutations are identified in key components of canonical and non-canonical Wnt signaling and in PLCs and precancerous lesions. In this review, the altered functions of Wnt/β-catenin signaling are considered in human PLCs, with emphasis on hepatocellular carcinomas (HCC), cholangiocarcinomas (CCA) and hepatoblastomas (HB). Based on recent literature, we also focused on liver cancerogenesis through Wnt deregulation. An overview of preclinical and clinical studies on approved and experimental drugs, targeting the Wnt/β-catenin cascade in PLCs, is proposed. In addition, the clinical implication of molecule inhibitors that have been shown to possess activity against the Wnt pathway in association with conventional surgical and loco-regional therapies are reviewed.

Cinnamaldehyde Relieves Induced Hepatocellular Carcinoma in Rat Model via Targeting Wnt/β-Catenin Pathway

Cinnamaldehyde (CA) is a natural compound that has promising biological activity. The current study investigates the antitumor activity of CA in thioacetamide induced hepatocellular carcinoma (HCC) in rats through targeting the Wnt/β-catenin pathway and evaluates the capability of CA to relieve hepatocytes oxidative stress in the HCC-rat model. After 16 weeks of HCC induction by thioacetamide (TAA), rats were treated for 7 consecutive weeks with CA daily; i.p. injection, Alpha-fetoprotein (AFP) level, necroinflammatory score and fibrosis percentage were measured to assess HCC development. The Wnt/β-catenin pathway was evaluated by measuring the hepatic protein level of Wnt-3a, β-catenin, cyclin D, matrix metalloproteinase-9 (MMP-9), and vascular endothelial growth factor (VEGF). Furthermore, hepatocytes’ oxidative stress was assessed by measuring hepatic GSH and MDA contents. Results showed that CA was significantly inhibiting the Wnt/β-catenin pathway through the downregulation of hepatic Wnt-3a, β-catenin, cyclin D, MMP-9, and VEGF. Moreover, CA ameliorates hepatocytes’ oxidative stress via lowering hepatic MDA content and rising hepatic GSH content. Thus, in conclusion, CA is a promising treatment for HCC. It not only has an effective antitumor activity but also ameliorates hepatocytes’ oxidative stress.

Signaling Pathways Involved in 5-FU Drug Resistance in Cancer

Anti-metabolite drugs prevent the synthesis of essential cell growth compounds. 5-fluorouracil is used as an anti-metabolic drug in various cancers in the first stage of treatment. Unfortunately, in some cancers, 5-fluorouracil has low effectiveness because of its drug resistance. Studies have shown that drug resistance to 5-fluorouracil is due to the activation of specific signaling pathways and increased expressions of enzymes involved in drug metabolites. However, when 5-fluorouracil is used in combination with other drugs, the sensitivity of cancer cells to 5-fluorouracil increases, and the effect of drug resistance is reversed. This study discusses how the function of 5-fluorouracil in JAK/STAT, Wnt, Notch, NF-κB, and hedgehogs in some cancers.

HBx increases chromatin accessibility and ETV4 expression to regulate dishevelled-2 and promote HCC progression

Hepatitis B virus (HBV) infection is the predominant causes of hepatocellular carcinoma (HCC). HBV X protein (HBx), as the most frequently integrated viral gene sequence following HBV infection, plays a critical role in the pathogenesis of HCC. H3K27ac is a characteristic marker for identifying active enhancers and even indicates chromatin accessibility associated with super-enhancers (SEs). In this study, H3K27ac ChIP-seq was applied for high-quality SE annotation of HBx-induced SEs and chromatin accessibility evaluation. The results indicated that HBx preferentially affects enrichment of H3K27ac in transcription factor signaling pathway genes, including ETV4. RNA-seq indicated that ETV4 is upregulated by HBx and that upregulated ETV4 promotes HCC progression. Interestingly, ETV4 was also included in the 568 cancer driver gene pool obtained by the Integrative OncoGenomics pipeline. However, the biological function and mechanism of ETV4 remain incompletely understood. In vivo and in vitro, we found that increased ETV4 expression promotes HCC cell migration and invasion by upregulating DVL2 and activating Wnt/β-catenin. The mRNA and protein levels of ETV4 are higher in tumor tissues compared with adjacent tissues, and high expression of ETV4 is associated with poor prognosis in HCC patients. In summary, we first confirm that ETV4 is significantly upregulated by HBx and involved in SE-associated chromatin accessibility. Increased expression of ETV4 promotes HCC cell invasion and metastasis by upregulating DVL2. The present study provides insight into the ETV4-DVL2-β-catenin axis in HBV-related HCC, which will be helpful for treating patients with aggressive HCC.

RNF43/ZNRF3 loss predisposes to hepatocellular-carcinoma by impairing liver regeneration and altering the liver lipid metabolic ground-state

RNF43/ZNRF3 negatively regulate WNT signalling. Both genes are mutated in several types of cancers, however, their contribution to liver disease is unknown. Here we describe that hepatocyte-specific loss of Rnf43/Znrf3 results in steatohepatitis and in increase in unsaturated lipids, in the absence of dietary fat supplementation. Upon injury, Rnf43/Znrf3 deletion results in defective hepatocyte regeneration and liver cancer, caused by an imbalance between differentiation/proliferation. Using hepatocyte-, hepatoblast- and ductal cell-derived organoids we demonstrate that the differentiation defects and lipid alterations are, in part, cell-autonomous. Interestingly, ZNRF3 mutant liver cancer patients present poorer prognosis, altered hepatic lipid metabolism and steatohepatitis/NASH signatures. Our results imply that RNF43/ZNRF3 predispose to liver cancer by controlling the proliferative/differentiation and lipid metabolic state of hepatocytes. Both mechanisms combined facilitate the progression towards malignancy. Our findings might aid on the management of those RNF43/ZNRF3 mutated individuals at risk of developing fatty liver and/or liver cancer.

Expanding uncapped translation and emerging function of circular RNA in carcinomas and noncarcinomas

Circular RNAs (circRNAs) are classified as noncoding RNAs because they are devoid of a 5' end cap and a 3' end poly (A) tail necessary for cap-dependent translation. However, increasing numbers of translated circRNAs identified through high-throughput RNA sequencing overlapping with polysome profiling indicate that this rule is being broken. CircRNAs can be translated in cap-independent mechanism, including IRES (internal ribosome entry site)-initiated pattern, MIRES (m6A internal ribosome entry site) -initiated patterns, and rolling translation mechanism (RCA). CircRNA-encoded proteins harbour diverse functions similar to or different from host proteins. In addition, they are linked to the modulation of human disease including carcinomas and noncarcinomas. CircRNA-related translatomics and proteomics have attracted increasing attention. This review discusses the progress and exclusive characteristics of circRNA translation and highlights the latest mechanisms and regulation of circRNA translatomics. Furthermore, we summarize the extensive functions and mechanisms of circRNA-derived proteins in human diseases, which contribute to a better understanding of intricate noncanonical circRNA translatomics and proteomics and their therapeutic potential in human diseases.

Wnt/β-catenin signalling: function, biological mechanisms, and therapeutic opportunities

The Wnt/β-catenin pathway comprises a family of proteins that play critical roles in embryonic development and adult tissue homeostasis. The deregulation of Wnt/β-catenin signalling often leads to various serious diseases, including cancer and non-cancer diseases. Although many articles have reviewed Wnt/β-catenin from various aspects, a systematic review encompassing the origin, composition, function, and clinical trials of the Wnt/β-catenin signalling pathway in tumour and diseases is lacking. In this article, we comprehensively review the Wnt/β-catenin pathway from the above five aspects in combination with the latest research. Finally, we propose challenges and opportunities for the development of small-molecular compounds targeting the Wnt signalling pathway in disease treatment.

Hepatocellular Carcinoma in Chronic Viral Hepatitis: Where Do We Stand?

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death. Although the burden of alcohol- and NASH-related HCC is growing, chronic viral hepatitis (HBV and HCV) remains a major cause of HCC development worldwide. The pathophysiology of viral-related HCC includes liver inflammation, oxidative stress, and deregulation of cell signaling pathways. HBV is particularly oncogenic because, contrary to HCV, integrates in the cell DNA and persists despite virological suppression by nucleotide analogues. Surveillance by six-month ultrasound is recommended in patients with cirrhosis and in "high-risk" patients with chronic HBV infection. Antiviral therapy reduces the risks of development and recurrence of HCC; however, patients with advanced chronic liver disease remain at risk of HCC despite virological suppression/cure and should therefore continue surveillance. Multiple scores have been developed in patients with chronic hepatitis B to predict the risk of HCC development and may be used to stratify individual patient's risk. In patients with HCV-related liver disease who achieve sustained virological response by direct acting antivirals, there is a strong need for markers/scores to predict long-term risk of HCC. In this review, we discuss the most recent advances regarding viral-related HCC.

Loss of hepatic miR-194 promotes liver regeneration and protects from acetaminophen-induced acute liver injury

The two microRNAs miR-192 and miR-194 are abundantly expressed in the liver and are considered serum biomarkers of liver injury. However, their role in the development of liver injury has not yet been determined. In this study, we generated miR-192/194 mutant mice and determined the effect of miR-192/194 loss on acetaminophen (APAP)-induced acute liver injury. With genetic depletion of miR-192/194, mutant mice were fertile and normally developed. No spontaneous liver injuries were observed in mutant mice. After APAP administration, mutant mice developed less severe liver damage than control mice. Specifically, mutant mice exhibited significantly lower serum alanine transaminase (ALT) levels and pericentral necrosis/apoptosis than control mice receiving APAP. β-catenin signaling was activated during the early phase of liver injury. Activated β-catenin signaling led to faster cellular proliferation and higher expression of AXIN2 and glutamine synthetases. After partial hepatectomy, the miR-192/194 mutant hepatocytes were more regenerative than control hepatocytes (as shown by BrdU incorporation). Moreover, in vitro experiments indicated that miR-194, but not miR-192, specifically repressed β-catenin signaling, while animal experiments revealed that chemical-mediated knockdown of β-catenin signaling compromised APAP resistance that liver protected from miR-192/194 genetic depletion. Collectively, our data indicated that the loss of miR-194 promoted liver regeneration and protected the liver from APAP-induced injury.

Targeting the Wnt Signaling Pathway in Liver Fibrosis for Drug Options: An Update

Liver fibrosis is a life-threatening disease, with challenging morbidity and mortality for healthcare systems worldwide. It imparts an enormous economic burden to societies, making continuous research and informational updates about its pathogenesis and treatment crucial. This review's focus is on the current knowledge about the Wnt signaling pathway, serving as an important pathway in liver fibrosis development and activation of hepatic stellate cells (HSCs). Two types of Wnt pathways are distinguished, namely the ß-catenin-dependent canonical and non-canonical Ca²⁺ or planar cell polarity (PCP)-dependent pathway. The dynamic balance of physiologically healthy liver and hepatocytes is disturbed by repeated liver injuries. Activation of the ß-catenin Wnt pathway prevents the regeneration of hepatocytes by the replacement of extracellular matrix (ECM), leading to the appearance of scar tissue and the formation of regenerated nodular hepatocytes, lacking the original function of healthy hepatocytes. Therefore, liver function is reduced due to the severely advanced disease. Selective inhibition of ß-catenin inhibits inflammatory processes (since chemokines and pro-inflammatory cytokines are produced during Wnt activation), reduces growth of activated HSCs and reduces collagen synthesis and angiogenesis, thereby reducing the progression of liver fibrosis in vivo. While the canonical Wnt pathway is usually inactive in a physiologically healthy liver, it shows activity during cell regeneration or renewal and in certain pathophysiological conditions, such as liver diseases and cancer. Targeted blocking of some of the basic components of the Wnt pathway is a therapeutic approach. These include the frizzled transmembrane receptor (Fz) receptors using the secreted frizzled-related protein family (sFRP), Fz-coreceptors low-density LRP 5/6 through dickkopf-related protein 1 (DKK1) or niclosamide, glycogen kinase-3 beta (GSK-3β) using SB-216763, cyclic-AMP response element-binding protein (CBP) using PRI-724 and ICG-001, the lymphoid enhancer binding factor (LEF)/T cell-specific transcription factor (TCF) system as well as Wnt inhibitory factor 1 (WIF1) and miR-17-5p using pinostilbene hydrate (PSH). Significant progress has been made in inhibiting Wnt and thus stopping the progression of liver fibrosis by diminishing key components for its action. Comprehending the role of the Wnt signaling pathway in liver fibrosis may lead to discovery of novel targets in liver fibrosis therapeutic strategies' development.

Metabolic Contributions of Wnt Signaling: More Than Controlling Flight

The canonical Wnt signaling pathway is ubiquitous throughout the body and influences a diverse array of physiological processes. Following the initial discovery of the Wnt signaling pathway during wing development in Drosophila melanogaster, it is now widely appreciated that active Wnt signaling in mammals is necessary for the development and growth of various tissues involved in whole-body metabolism, such as brain, liver, pancreas, muscle, and adipose. Moreover, elegant gain- and loss-of-function studies have dissected the tissue-specific roles of various downstream effector molecules in the regulation of energy homeostasis. This review attempts to highlight and summarize the contributions of the Wnt signaling pathway and its downstream effectors on whole-body metabolism and their influence on the development of metabolic diseases, such as diabetes and obesity. A better understanding of the Wnt signaling pathway in these tissues may aid in guiding the development of future therapeutics to treat metabolic diseases.

The hippo pathway: A master regulator of liver metabolism, regeneration, and disease

The liver is the only visceral organ in the body with a tremendous capacity to regenerate in response to insults that induce inflammation, cell death, and injury. Liver regeneration is a complicated process involving a well-orchestrated activation of non-parenchymal cells in the injured area and proliferation of undamaged hepatocytes. Furthermore, the liver has a Hepatostat, defined as adjustment of its volume to that required for homeostasis. Understanding the mechanisms that control different steps of liver regeneration is critical to informing therapies for liver repair, to help patients with liver disease. The Hippo signaling pathway is well known for playing an essential role in the control and regulation of liver size, regeneration, stem cell self-renewal, and liver cancer. Thus, the Hippo pathway regulates dynamic cell fates in liver, and in absence of its downstream effectors YAP and TAZ, liver regeneration is severely impaired, and the proliferative expansion of liver cells blocked. We will mainly review upstream mechanisms activating the Hippo signaling pathway following partial hepatectomy in mouse model and patients, its roles during different steps of liver regeneration, metabolism, and cancer. We will also discuss how targeting the Hippo signaling cascade might improve liver regeneration and suppress liver tumorigenesis.

Loss of Thymine DNA Glycosylase Causes Dysregulation of Bile Acid Homeostasis and Hepatocellular Carcinoma

Thymine DNA glycosylase (TDG) is a nuclear receptor coactivator that plays an essential role in the maintenance of epigenetic stability in cells. Here, we demonstrate that the conditional deletion of TDG in adult mice results in a male-predominant onset of hepatocellular carcinoma (HCC). TDG loss leads to a prediabetic state, as well as bile acid (BA) accumulation in the liver and serum of male mice. Consistent with these data, TDG deletion led to dysregulation of the farnesoid X receptor (FXR) and small heterodimer partner (SHP) regulatory cascade in the liver. FXR and SHP are tumor suppressors of HCC and play an essential role in BA and glucose homeostasis. These results indicate that TDG functions as a tumor suppressor of HCC by regulating a transcriptional program that protects against the development of glucose intolerance and BA accumulation in the liver.

Systems Pharmacology Study of the Anti-Liver Injury Mechanism of Citri Reticulatae Pericarpium

Liver diseases are mostly triggered by oxidative stress and inflammation, leading to extracellular matrix overproduction and prone to develop into liver fibrosis, cirrhosis and hepatocellular carcinoma. Liver injury (LI) refers to various pathogenic factors leading to the destruction of stem cells that then affect the liver's normal function, causing a series of symptoms and abnormal liver function indicators. Citri Reticulatae Pericarpium (CRP) is one of the most commonly used traditional Chinese medicines; it contains flavonoids including hesperidin, nobiletin, and tangeretin. CRP has antibacterial, antioxidant, and antitumor effects that reduce cholesterol, prevent atherosclerosis and decrease LI. Here we analyzed the components of CRP and their targets of action in LI treatment and assessed the relationships between them using a systems pharmacology approach. Twenty-five active ingredients against LI were selected based on ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry results and databases. The drug targets and disease-related targets were predicted. The 117 common targets were used to construct a protein-protein interaction network. We identified 1719 gene ontology items in LI treatment, including 1,525 biological processes, 55 cellular components, and 139 molecular functions. These correlated with 49 Kyoto Encyclopedia of Genes and Genomes pathways. These findings suggest that CRP may counteract LI by affecting apoptotic, inflammatory, and energy metabolism modules. In vitro experiments suggested that the mechanism may involve hesperidin and naringenin acting on CASP3, BAX, and BCL2 to affect the apoptosis pathway, attenuating liver fibrosis. Naringenin significantly inhibited AKT1 phosphorylation, which in turn mediated activation of the phosphoinositide 3-kinase-Akt signaling pathways against LI. This study provides a reference for systematically exploring the mechanism of CRP's anti-LI action and is also expands of the application of systems pharmacology in the study of traditional Chinese medicine.

LncRNA NBR2 aggravates hepatoblastoma cell malignancy and promotes cell proliferation under glucose starvation through the miR-22/TCF7 axis

Hepatoblastoma (HB) is the most commonly seen pediatric liver malignancy. With frequent mutations in CTNNB1 gene that encodes β-catenin, hepatoblastoma has been considered as a Wnt/β-catenin-activated malignant tumor. Altered glucose metabolism upon nutrient deprivation (glucose starvation) might also be a critical event in hepatoblastoma carcinogenesis. The present study provides a lncRNA NBR2/miR-22/TCF7 axis modulating proliferation, invasion, migration, and apoptosis of hepatoblastoma cells upon glucose starvation through Wnt and downstream TCF7 signaling pathways. The expression of NBR2 is significantly increased within hepatoblastoma tissue samples; moreover, under incubation with 0 mM glucose (glucose starvation), NBR2 expression is significantly upregulated. NBR2 silencing not only inhibited hepatoblastoma cell viability, invasion, and migration under normal culture condition but also promoted the cell apoptosis under glucose starvation. NBR2 silencing in hepatoblastoma cells also decreased TCF7 mRNA expression and TCF7 protein levels, as well as the protein levels of the cell cycle, glucose entrapment, and EMT markers. miR-22 is directly bound to both NBR2 and TCF7; lncRNA NBR2 counteracted miR-22-mediated repression on TCF7 via acting as a ceRNA. The effects of NBR2 silencing on TCF7 expression, hepatoblastoma cell phenotype, and cell cycle, glucose entrapment, and EMT markers were all significantly reversed by miR-22 inhibition. In conclusion, lncRNA NBR2 aggravates hepatoblastoma cell malignancy through competing with TCF7 for miR-22 binding, therefore counteracting miR-22-mediated repression on TCF7. LncRNA NBR2 might be a promising target to inhibit hepatoblastoma cell proliferation under glucose starvation.

Bone Marrow-Derived Mesenchymal Stem Cells Differentially Affect Glioblastoma Cell Proliferation, Migration, and Invasion: A 2D-DIGE Proteomic Analysis

Bone marrow-derived mesenchymal stem cells (BM-MSCs) display high tumor tropism and cause indirect effects through the cytokines they secrete. However, the effects of BM-MSCs on the biological behaviors of glioblastoma multiforme remain unclear. In this study, the conditioned medium from BM-MSCs significantly inhibited the proliferation of C6 cells (P < 0.05) but promoted their migration and invasion (P < 0.05). Two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) proteomic analysis revealed 17 proteins differentially expressed in C6 cells exposed to the BM-MSC-conditioned medium including five upregulated proteins and 12 downregulated proteins. Among these, six differentially expressed proteins (Calr, Set, Oat, Npm1, Ddah1, and Tardbp) were closely related to cell proliferation and differentiation, and nine proteins (Pdia6, Sphk1, Anxa4, Vim, Tuba1c, Actr1b, Actn4, Rap2c, and Tpm2) were associated with motility and the cytoskeleton, which may modulate the invasion and migration of tumor cells. Above all, by identifying the differentially expressed proteins using proteomics and bioinformatics analysis, BM-MSCs could be genetically modified to specifically express tumor-suppressive factors when BM-MSCs are to be used as tumor-selective targeting carriers in the future.

TMEM9-v-ATPase Activates Wnt/β-Catenin Signaling Via APC Lysosomal Degradation for Liver Regeneration and Tumorigenesis

BACKGROUND AND AIMS

How Wnt signaling is orchestrated in liver regeneration and tumorigenesis remains elusive. Recently, we identified transmembrane protein 9 (TMEM9) as a Wnt signaling amplifier.

APPROACH AND RESULTS

TMEM9 facilitates v-ATPase assembly for vesicular acidification and lysosomal protein degradation. TMEM9 is highly expressed in regenerating liver and hepatocellular carcinoma (HCC) cells. TMEM9 expression is enriched in the hepatocytes around the central vein and acutely induced by injury. In mice, Tmem9 knockout impairs hepatic regeneration with aberrantly increased adenomatosis polyposis coli (Apc) and reduced Wnt signaling. Mechanistically, TMEM9 down-regulates APC through lysosomal protein degradation through v-ATPase. In HCC, TMEM9 is overexpressed and necessary to maintain β-catenin hyperactivation. TMEM9-up-regulated APC binds to and inhibits nuclear translocation of β-catenin, independent of HCC-associated β-catenin mutations. Pharmacological blockade of TMEM9-v-ATPase or lysosomal degradation suppresses Wnt/β-catenin through APC stabilization and β-catenin cytosolic retention.

CONCLUSIONS

Our results reveal that TMEM9 hyperactivates Wnt signaling for liver regeneration and tumorigenesis through lysosomal degradation of APC.

Molecular Mechanisms of Hepatoblastoma

Hepatoblastoma (HB) is the predominant primary liver tumor in children. While the prognosis is favorable when the tumor can be resected, the outcome is dismal for patients with progressed HB. Therefore, a better understanding of the molecular mechanisms responsible for HB is imperative for early detection and effective treatment. Sequencing analysis of human HB specimens unraveled the pivotal role of Wnt/β-catenin pathway activation in this disease. Nonetheless, β-catenin activation alone does not suffice to induce HB, implying the need for additional alterations. Perturbations of several pathways, including Hippo, Hedgehog, NRF2/KEAP1, HGF/c-Met, NK-1R/SP, and PI3K/AKT/mTOR cascades and aberrant activation of c-MYC, n-MYC, and EZH2 proto-oncogenes, have been identified in HB, although their role requires additional investigation. Here, we summarize the current knowledge on HB molecular pathogenesis, the relevance of the preclinical findings for the human disease, and the innovative therapeutic strategies that could be beneficial for the treatment of HB patients.

Probing the Mechanism of Hepatotoxicity of Hexabromocyclododecanes through Toxicological Network Analysis

The prediction and mechanism analysis of hepatotoxicity of contaminants, because of their various phenotypes and complex mechanisms, is still a key problem in environmental research. We applied a toxicological network analysis method to predict the hepatotoxicity of three hexabromocyclododecane (HBCD) diastereoisomers (α-HBCD, β-HBCD, and γ-HBCD) and explore their potential mechanisms. First, we collected the hepatotoxicity related genes and found that those genes were significantly localized in the human interactome. Therefore, these genes form a disease module of hepatotoxicity. We also collected targets of α-, β-, and γ-HBCD and found that their targets overlap with the hepatotoxicity disease module. Then, we trained a model to predict hepatotoxicity of three HBCD diastereoisomers based on the relationship between the hepatotoxicity disease module and targets of compounds. We found that 593 genes were significantly located in the hepatotoxicity disease module (Z = 11.9, p < 0.001) involved in oxidative stress, cellular immunity, and proliferation, and the accuracy of hepatotoxicity prediction of HBCD was 0.7095 ± 0.0193 and the recall score was 0.8355 ± 0.0352. HBCD mainly affects the core disease module genes to mediate the adenosine monophosphate-activated kinase, p38MAPK, PI3K/Akt, and TNFα pathways to regulate the immune reaction and inflammation. HBCD also induces the secretion of IL6 and STAT3 to lead hepatotoxicity by regulating NR3C1. This approach is transferable to other toxicity research studies of environmental pollutants.

Functional compensation precedes recovery of tissue mass following acute liver injury

The liver plays a central role in metabolism, protein synthesis and detoxification. It possesses unique regenerative capacity upon injury. While many factors regulating cellular proliferation during liver repair have been identified, the mechanisms by which the injured liver maintains vital functions prior to tissue recovery are unknown. Here, we identify a new phase of functional compensation following acute liver injury that occurs prior to cellular proliferation. By coupling single-cell RNA-seq with in situ transcriptional analyses in two independent murine liver injury models, we discover adaptive reprogramming to ensure expression of both injury response and core liver function genes dependent on macrophage-derived WNT/β-catenin signaling. Interestingly, transcriptional compensation is most prominent in non-proliferating cells, clearly delineating two temporally distinct phases of liver recovery. Overall, our work describes a mechanism by which the liver maintains essential physiological functions prior to cellular reconstitution and characterizes macrophage-derived WNT signals required for this compensation.

The liver possesses the ability to regenerate following sudden injury. Here, the authors use single-cell RNA-sequencing and in situ transcriptional analyses to identify a new phase of liver regeneration in mice aimed at maintaining essential functions throughout the regenerative process.

Evodiamine: A review of its pharmacology, toxicity, pharmacokinetics and preparation researches

ETHNOPHARMACOLOGICAL RELEVANCE

Evodia rutaecarpa, a well-known herb medicine in China, is extensively applied in traditional Chinese medicine (TCM). The plant has the effects of dispersing cold and relieving pain, arresting vomiting, and helping Yang and stopping diarrhea. Modern research demonstrates that evodiamine, the main component of Evodia rutaecarpa, is the material basis for its efficacy.

AIMS OF THE REVIEW

This paper is primarily addressed to summarize the current studies on evodiamine. The progress in research on the pharmacology, toxicology, pharmacokinetics, preparation researches and clinical application are reviewed. Moreover, outlooks and directions for possible future studies concerning it are also discussed.

MATERIALS AND METHODS

The information of this systematic review was conducted with resources of multiple literature databases including PubMed, Google scholar, Web of Science and Wiley Online Library and so on, with employing a combination of keywords including "pharmacology", "toxicology", "pharmacokinetics" and "clinical application", etc. RESULTS: As the main component of Evodia rutaecarpa, evodiamine shows considerable pharmacological activities, such as analgesic, anti-inflammatory, anti-tumor, anti-microbial, heart protection and metabolic disease regulation. However, it is also found that it has significant hepatotoxicity and cardiotoxicity, thereby it should be monitored in clinical. In addition, available data demonstrate that the evodiamine has a needy solubility in aqueous medium. Scientific and reasonable pharmaceutical strategies should be introduced to improve the above defects. Meanwhile, more efforts should be made to develop novel efficient and low toxic derivatives.

CONCLUSIONS

This review summarizes the results from current studies of evodiamine, which is one of the valuable medicinal ingredients from Evodia rutaecarpa. With the assistance of relevant pharmacological investigation, some conventional application and problems in pharmaceutical field have been researched in recent years. In addition, unresolved issues include toxic mechanisms, pharmacokinetics, novel pharmaceutical researches and relationship between residues and intestinal environment, which are still being explored and excavate before achieving integration into clinical practice.

LncRNA ANCR Suppresses the Progression of Hepatocellular Carcinoma Through the Inhibition of Wnt/β-Catenin Signaling Pathway

Objective

Our study aimed to investigate the effect of anti-differentiation noncoding RNA (ANCR) on hepatocellular carcinoma (HCC) and its potential molecular mechanisms.

Methods

The expression of ANCR was detected by qRT-RCR in both HCC tissues and HCC cells. Moreover, the relationship between ANCR expression and clinical parameters in HCC patients was investigated. The proliferation, cell clones, migration, invasion and apoptosis of MHCC97H and HCCLM3 cells were measured by MTT assay, colony formation assay, transwell assay and flow cytometry, respectively. The expressions of N-cadherin, vimentin, E-cadherin, cleaved caspase-3, Bax, Bcl-2, Wnt1, β-catenin and GSK-3β in MHCC97H and HCCLM3 cells were measured by Western blot.

Results

Our results showed that ANCR was lowly expressed in both HCC tissues and HCC cells. ANCR expression was closely associated with tumor size, tumor-node-metastasis (TNM) stages and vascular invasion in HCC. ANCR could dramatically inhibit cell proliferation, migration and invasion, as well as promote apoptosis in MHCC97H and HCCLM3 cells. ANCR could significantly increase the expression of cleaved caspase-3, Bax, E-cadherin and GSK-3β but reduce the expression of Bcl-2, N-cadherin, vimentin, Wnt1 and β-catenin in MHCC97H and HCCLM3 cells. In addition, Wnt/β-catenin pathway inhibitor (IWP-2) partially reversed the effects of silencing ANCR on the proliferation, migration, invasion and apoptosis of HCCLM3 cells.

Conclusion

Our study demonstrated that ANCR can suppress cell proliferation, migration and invasion, as well as promote apoptosis of HCC cells via modulation of the Wnt/β-catenin signaling pathway.

Dishevelled Associated Activator Of Morphogenesis (DAAM) Facilitates Invasion of Hepatocellular Carcinoma by Upregulating Hypoxia-Inducible Factor 1α (HIF-1α) Expression

Background

The dishevelled associated activator of morphogenesis (DAAM) family, consisting of DAAM1 and DAAM2, is an important component of the Wnt signal pathway. Previous studies have suggested that DAAM2 reduces Von Hippel-Lindau (VHL) expression by promoting its ubiquitination, but the correlation between DAAM and HIF-1α in hepatocellular carcinoma (HCC) has not been studied.

Material/Methods

In our study, expression of DAAM1 and DAAM2 in HCCs and tumor-adjacent liver tissues was assessed with qRT-PCR and immunohistochemistry. Correlations between DAAM1/2 and the clinicopathologic variables were evaluated with the Chi-square test. With univariate and multivariate analysis, we further evaluated the prognostic significance of DAAM1 and DAAM2. Using in vitro experiments, we assessed the functions of DAAM1 and DAAM2 in invasion and proliferation in different HCC cell lines and investigated their underlying mechanisms.

Results

DAAM1 and 2 overexpression were 18.8% and 48.7%, respectively, of the whole cohort. mRNAs of DAAM2 in HCCs were substantially higher than mRNAs in liver tissues, while DAAM1 mRNA had no marked difference. High DAAM2 expression was notably associated with advanced T stage (P=0.032), TNM stage (P=0.032), and overall survival (OS) rate (P=0.004). DAAM 2 knockdown promoted VHL accumulation and subsequent HIF-1α down-regulation in HCC cells. In HCC specimens, DAAM2 expression was also negatively correlated with VHL and positively associated with HIF-1α. Moreover, HIF-1α was required in DAAM2-induced invasion of HCC cells.

Conclusions

DAAM2, rather than DAAM1, was able to predict prognosis of HCC. DAAM2 decreased VHL expression and consequently upregulated HIF-1α, eventually facilitating invasion of HCC.

Waterborne Cu exposure increased lipid deposition and lipogenesis by affecting Wnt/β-catenin pathway and the β-catenin acetylation levels of grass carp Ctenopharyngodon idella

Lipid metabolism could be used as a biomarker for environmental monitoring of metal pollution, including Cu. Given the potential role of the Wnt/β-catenin signaling pathway and acetylation in lipid metabolism, the aim of this study was to investigate the mechanism of Wnt signaling and acetylation mediating Cu-induced lipogenesis. Grass carp Ctenopharyngodon idella, widely distributed freshwater teleost, were used as the model. We found that waterborne Cu exposure increased the accumulation of Cu and lipid, up-regulated lipogenesis, suppressed Wnt signaling, reduced β-catenin protein level and its nuclear location, reduced the sirt1 mRNA levels and up-regulated the β-catenin acetylation level. Further investigation found that Cu up-regulated lipogenesis through Wnt/β-catenin pathway; Cu regulated the β-catenin acetylation, and K311 was the key acetylated residue after Cu incubation. SIRT1 mediated Cu-induced changes of acetylated β-catenin and played an essential role in nuclear accumulation of β-catenin and Cu-induced lipogenesis. Cu facilitated lipid accumulation via the regulation of Wnt pathway by SIRT1. For the first time, our study uncovered the novel mechanism for Wnt/β-catenin pathway and β-catenin acetylation levels mediating Cu-induced lipid deposition, which provided insights into the association between Cu exposure and lipid metabolism in fish and had important environmental implications for monitoring metal pollution in the water by using new biomarkers involved in lipid metabolism.

The paradox of dipeptidyl peptidase IV inhibition in enterocytic differentiation and epithelial-mesenchymal transition in rat cholestatic sepsis

Proper enterocytic proliferation/differentiation, besides providing adequate adherens junctions (AJ) integrity, are responsible for strengthening of the gut barrier that acts as a first line defense against endotoxemia. However, the preferential role of the underlying PI3K/Akt (PKB) axis in triggering enterocytic proliferation/differentiation signaling and AJ assembly is still obscure in sepsis. Additionally, the potential involvement of dipeptidyl peptidase (DPP)-IV in cholestatic sepsis has not yet been reported. Common bile duct ligation (CBDL) insult was performed in adult male Sprague-Dawley rats except for sham operated animals; three doses of vildagliptin (VLD3, 10 and 30 mg/kg/d; p.o) were administered for 10 consecutive days post CBDL. VLD3/10/30 dose-dependently decreased DPP-IV and elevated GLP-1, IGF-1, PI3K, pS473-Akt (PKB), pS9-GSK-3β, pS133-CREB and cyclin-D1. VLD3/10 reduced fever, portal/aortic endotoxin and IgG, body weight loss as well as ileal NF-κB, TNF-α, MPO, TBARS, subepithelial/pericryptal and submucosal collagen deposition, vimentin immunoreactivity, N-cadherin, Zeb1 and pY654-β-catenin but increased E-cadherin, NPSH and colon/spleen indices - effects that were quite the opposite of VLD30. Accordingly, maintaining proper enterocytic proliferation/differentiation and phosphorylation inputs consequent to adequate DPP-IV inhibition is integral to AJ assembly in cholestatic sepsis; however, perturbed signals by excessive suppression of the enzyme activity induce toxic effects manifested as AJ disassembly and EMT, hence gut leakage and overt endotoxemia.

Complement C1q mediates the expansion of periportal hepatic progenitor cells in senescence-associated inflammatory liver

Most hepatocellular carcinomas (HCCs) develop in patients with chronic hepatitis, which creates a microenvironment for the growth of hepatic progenitor cells (HPCs) at the periportal area and subsequent development of HCCs. We investigated the signal from the inflammatory liver for this pathogenic process in the hepatic conditional β-catenin knockout mouse model. Senescent β-catenin-depleted hepatocytes in aged mice create an inflammatory microenvironment that stimulates periportal HPC expansion but arrests differentiation, which predisposes mice to the development of liver tumors. The release of complement C1q from macrophages in the inflammatory niche was identified as the unorthodox signal that activated the β-catenin pathway in periportal HPCs and was responsible for their expansion and de-differentiation. C1q inhibitors blocked the β-catenin pathway in both the expanding HPCs and the liver tumors but spared its orthodox pathway in pericentral normal hepatocytes. This mechanism has been validated in human liver specimens from patients with chronic hepatitis. Taken together, these results demonstrate that C1q- mediated activation of β-catenin pathway in periportal HPCs is a previously unrecognized mechanism for replenishing hepatocytes in the inflammatory liver and, if unchecked, for promoting hepatocarcinogenesis. C1q may become a new target for blocking carcinogenesis in patients with chronic hepatitis.

Evodiamine and rutaecarpine from Tetradium ruticarpum in the treatment of liver diseases

BACKGROUND

Liver is the pivotal organ responsible for plasma protein production, biliary secretion, xenobiotic elimination, glucose and lipid homeostasis. Dysregulation of these functions usually leads to liver diseases and further related complications. The incidence of liver diseases is increasing worldwide, with high morbidity and mortality when at advanced stages, and has become significant public health concern and substential economic burden. Thus, novel therapeutic strategies for managing liver diseases progression are urgently required. T. ruticarpum is one of the most famous and frequently used herbal medicine and has been prescribed in traditional Chinese medicine (TCM) formulas for the treatment of various ailments, including liver diseases. A considerable amount of bioactive ingredients have been isolated and identified from the roots of T. ruticarpum, including alkaloids, saponins, phenols, volatile oils and other compounds. Among these compounds, evodiamine (EVO) and rutaecarpine (RUT) are believed to be the most bioactive compounds.

PURPOSE

To summarize recent findings regarding to the metabolism, pharmacological/toxicological effects of EVO and RUT and to highlight the potential therapeutic effects of them against liver diseases.

METHODS

Online academic databases (including PubMed, Google Scholar, Web of Science and CNKI) were searched using search terms of "T. ruticarpum", "Wu Zhu Yu", "evodiamine", "rutaecarpine", "liver" and combinations to include published studies of EVO and RUT primarily from 2004-2019. Several critical previous studies beyond this period were also included.

RESULTS

Evodiamine (EVO) and rutaecarpine (RUT) are believed to be the most bioactive alkaloids in T. ruticarpum, having anti-inflammation, anti-fibrosis, anti-lipotoxicity, anti-cancer activities, and thus having potential to improve liver disorders. In the current review, we comprehensively summarized recent progresses in the studies of EVO- and RUT-mediated promising hepatoprotective effects and also provide novel insights regarding the potential use of EVO and RUT as therapeutic options for the treatment of liver diseases.

CONCLUSION

With further in-depth pharmacology and pharmacokinetic studies, we believe that natural products in T. ruticarpum and their derivatives will become promising medicines with improved clinical efficacy for the treatment of liver diseases in the immediate future.

Prohibitin 1 in liver injury and cancer

Prohibitin 1 is an evolutionary conserved and ubiquitously expressed protein that exerts different biological functions depending on its subcellular localization. The role of prohibitin 1 in liver cancer is controversial as it can be pro- or anti-tumorigenic. However, most of the studies to date have described prohibitin 1 primarily as a tumor suppressor in the liver. Its deficiency sensitizes the liver to cholestatic liver injury, non-alcoholic fatty liver disease, inflammatory insults, and cancer. Liver-specific Phb1-knockout mice spontaneously develop hepatocellular carcinoma, Phb1 heterozygotes are more susceptible to develop cholangiocarcinoma, and the majority of human hepatocellular carcinomas and cholangiocarcinomas have reduced prohibitin 1 expression. Consistent with a tumor suppressive role in the liver, prohibitin 1 negatively regulates proliferation in hepatocytes and human hepatocellular carcinoma and cholangiocarcinoma cell lines, and multiple oncogenic signaling pathways are activated when prohibitin 1 is deficient. Although best known as a mitochondrial chaperone, prohibitin 1 can protect the liver by mitochondrial-independent mechanisms. This review summarizes what’s known about prohibitin 1’s role in liver pathology, with the focus on hepatoprotection and carcinogenesis.

Impact statement

This review summarizes the last decades of research on PHB1 in liver pathobiology. PHB1 is a key player for liver health as it is hepatoprotective and tumor suppressive. We highlight the importance of PHB1’s subcellular localization, post-translational modifications, and interacting proteins as major determinants of PHB1 cytoprotective function and anti-tumor activity in the liver.

Translation and functional roles of circular RNAs in human cancer

Circular RNAs (circRNAs) are a new class of non-coding RNAs formed by covalently closed loops through backsplicing. Recent methodologies have enabled in-depth characterization of circRNAs for identification and potential functions. CircRNAs play important roles in various biological functions as microRNA sponges, transcriptional regulators and combining with RNA binding proteins. Recent studies indicated that some cytoplasmic circRNAs can be effectively translated into detectable peptides, which enlightened us on the importance of circRNAs in cellular physiology function. Internal Ribosome Entry site (IRES)- and N⁶-methyladenosines (m⁶A)-mediated cap-independent translation initiation have been suggested to be potential mechanism for circRNA translation. To date, several translated circRNAs have been uncovered to play pivotal roles in human cancers. In this review, we introduced the properties and functions of circRNAs, and characterized the possible mechanism of translation initiation and complexity of the translation ability of circRNAs. We summarized the emerging functions of circRNA-encoded proteins in human cancer. The works on circRNA translation will open a hidden human proteome, and enhance us to understand the importance of circRNAs in human cancer, which has been poorly explored so far.

AXIN2+ Pericentral Hepatocytes Have Limited Contributions to Liver Homeostasis and Regeneration

The existence of specialized liver stem cell populations, including AXIN2⁺ pericentral hepatocytes, that safeguard homeostasis and repair has been controversial. Here, using AXIN2 lineage tracing in BAC-transgenic mice, we confirm the regenerative potential of intestinal stem cells (ISCs) but find limited roles for pericentral hepatocytes in liver parenchyma homeostasis. Liver regrowth following partial hepatectomy is enabled by proliferation of hepatocytes throughout the liver, rather than by a pericentral population. Periportal hepatocyte injury triggers local repair as well as auxiliary proliferation in all liver zones. DTA-mediated ablation of AXIN2⁺ pericentral hepatocytes transiently disrupts this zone, which is reestablished by conversion of pericentral vein-juxtaposed glutamine synthetase (GS)^- hepatocytes into GS⁺ hepatocytes and by compensatory proliferation of hepatocytes across liver zones. These findings show hepatocytes throughout the liver can upregulate AXIN2 and LGR5 after injury and contribute to liver regeneration on demand, without zonal dominance by a putative pericentral stem cell population.

Diwu Yanggan Modulates the Wnt/β-catenin Pathway and Inhibits Liver Carcinogenesis Signaling in 2-AAF/PH Model Rats

The activation of the Wnt/β-catenin signaling pathway in oval cells after liver injury is implicated in hepatocarcinogenesis. Diwu Yanggan capsule is a Chinese herbal medicine that has been used for treating liver disorder. The present study aimed to examine the mechanism by which Diwu Yanggan inhibits liver carcinogenesis, and the involvement of the Wnt/β-catenin signaling pathway. Diwu Yanggan capsule was administered to 2-acetaminofluorene/partial hepatectomy (2-AAF/PH) rats, a murine model of liver injury. The biomarkers of oval cells and key proteins in the Wnt/β-catenin signaling pathway were assessed on postoperative day 8, 10, 14, 17, 19 and 22. The results showed that treatment with Diwu Yanggan was associated with reduced expression of oval cell and stem cell biomarkers in the 2-AAF/PH animals. The expression pattern of key proteins in the Wnt/β-catenin pathway was altered in Diwu Yanggan-treated animals, indicating that the Diwu Yanggan treatment accelerated the activation of the Wnt/β-catenin pathway in the initial stage and contributed to its deactivation in the later stage. Histological findings indicated that hepatocyte proliferation was suppressed in Diwu Yanggan-treated animals, compared with untreated 2-AAF/PH animals. Taken together, Diwu Yanggan capsule may reduce the risk of hepatocarcinogenesis by modulating the Wnt/β-catenin signaling pathway.

CCL14 serves as a novel prognostic factor and tumor suppressor of HCC by modulating cell cycle and promoting apoptosis

CCL14 is a member of CC chemokines and its role in hepatocellular carcinoma (HCC) is still unknown. In this study, CCL14 expression were analyzed by tissue microarray (TMA) including 171 paired tumor and peritumor tissues of patients from Zhongshan Hospital of Fudan University. We found for the first time that CCL14 was downregulated in HCC tumor tissues compared with peritumor tissues (P = 0.01). Meanwhile, CCL14 low expression in HCC tumor tissues is associated with a poor prognosis (P = 0.035). CCL14 also displayed its predictive value in high differentiation (P = 0.026), liver cirrhosis (P = 0.003), and no tumor capsule (P = 0.024) subgroups. The underlying mechanisms were further investigated in HCC cell lines by CCL14 overexpression and knock-down in vitro. We found overexpression of CCL14 suppressed proliferation and promoted apoptosis of HCC cells. Finally, the effect was confirmed by animal xenograft tumor models in vivo. The results shown overexpression of CCL14 lead to inhibiting the growth of tumor in nude mice. Interestingly, our data also implied that CCL14 played these effects by inhibiting the activation of Wnt/β-catenin pathway. These findings suggest CCL14 is a novel prognostic factor of HCC and serve as a tumor suppressor.