Hepatic Carcinogenesis Research Articles

LncRNA TUG1 functions as a ceRNA for miR-1-3p to promote cell proliferation in hepatic carcinogenesis.

BackgroundHepatocellular carcinoma (HCC) is characterised by high malignancy, metastasis and recurrence, but the specific mechanism that drives these outcomes is unclear. Recent studies have shown that long noncoding RNAs (lncRNAs) can regulate the proliferation and apoptosis of hepatic cells.MethodsWe searched for lncRNAs and microRNAs (miRNAs), which can regulate IGF1 expression, through a bioinformatics website, and predicted that lncRNA taurine‐upregulated gene 1 (TUG1) would have multiple targets for miR‐1‐3p binding, meaning that lncRNA TUG1 played an adsorption role. A double luciferase assay was used to verify the targeting relationship between lncRNA TUG1 and miR‐1‐3p. Western blotting and qPCR were used to verify the targeting relationship between miR‐1‐3p and IGF1, and qPCR was used to verify the regulatory relationship between the lncRNA TUG1‐miR‐1‐3p‐IGF1 axis. CCK‐8 was used to detect the growth activity of miRNA‐transfected L‐O2 cells, and flow cytometry was used to detect cell cycle changes and apoptosis.ResultThe proliferation cycle of L‐O2 cells transfected with miR‐1‐3p mimics was significantly slowed. Flow cytometry showed that the proliferation of L‐O2 cells was slowed, and the apoptosis rate was increased. In contrast, when L‐O2 cells were transfected with miR‐1‐3p inhibitor, the expression of IGF1 was significantly upregulated, and the cell proliferation cycle was significantly accelerated. Flow cytometry showed that the cell proliferation rate was accelerated, and the apoptosis rate was reduced.ConclusionLncRNA TUG1 can adsorb miR‐1‐3p as a competitive endogenous RNA (ceRNA) to promote the expression of IGF1 and promote cell proliferation in hepatic carcinogenesis.

Diabetes medications and risk of HCC.

Type 2 diabetes mellitus is a recognized risk factor for HCC in patients with liver disease, independent from the etiology of their liver disease. Hence, prevention and treatment of type 2 diabetes mellitus and its underlying cause, insulin resistance, should be considered a treatment target for patients with liver disease. The drug armamentarium for diabetes is wide and consists of agents with insulin-sensitizing activity, agents that stimulate insulin secretion, insulin itself, and agents that reduce gastrointestinal and urinary glucose absorption. From an endocrinology perspective, the main goal of treatment is the achievement of euglycemia; however, in patients at risk of, or with known underlying liver disease, the choice of diabetic medication as it relates to potential hepatic carcinogenesis remains complex and should be carefully considered. In the last decade, increasing evidence has suggested that metformin may reduce the risk of HCC, whereas evidence for other classes of diabetic medications, particularly some of the newer agents including the sodium glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists, is fewer and often inconsistent. In this review, we aim to summarize the current evidence on the potential effects of the most widely used diabetic agents on liver cancer tumorigenesis.

Impact of HCV Infection on Hepatocyte Polarity and Plasticity

The hepatitis C virus (HCV) is an oncogenic virus that alters the cell polarization machinery in order to enter the hepatocyte and replicate. While these alterations are relatively well defined, their consequences in the evolution of the disease remain poorly documented. Since 2012, HCV infection can be effectively cured with the advent of direct acting antivirals (DAA). Nevertheless, patients cured of their HCV infection still have a high risk of developing hepatocellular carcinoma (HCC). Importantly, it has been shown that some of the deregulations induced by HCV are maintained despite a sustained virologic response (SVR), including the down-regulation of some hepatocyte functions such as bile acid metabolism, exemplifying cell dedifferentiation, and the up-regulation of the epithelial–mesenchymal transition (EMT). EMT is a process by which epithelial cells lose their differentiation and their specific polarity to acquire mesenchymal cell properties, including migration and extracellular matrix remodeling capabilities. Of note, epithelial cell polarity acts as a gatekeeper against EMT. Thus, it remains important to elucidate the mechanisms by which HCV alters polarity and promotes EMT that could participate in viral-induced hepatic carcinogenesis. In this review, we define the main steps involved in the polarization process of epithelial cells and recall the essential cellular actors involved. We also highlight the particularities of hepatocyte polarity, responsible for their unique morphology. We then focus on the alterations by HCV of epithelial cell polarity and the consequences of the transformation of hepatocytes involved in the carcinogenesis process.

Oncostatin M is overexpressed in NASH-related hepatocellular carcinoma and promotes cancer cell invasiveness and angiogenesis.

Oncostatin M (OSM) is a pleiotropic cytokine of the interleukin (IL)‐6 family that contributes to the progression of chronic liver disease. Here we investigated the role of OSM in the development and progression of hepatocellular carcinoma (HCC) in non‐alcoholic fatty liver disease (NAFLD)/non‐alcoholic steatohepatitis (NASH). The role of OSM was investigated in (1) selected cohorts of NAFLD/NASH HCC patients, (2) liver cancer cells exposed to human recombinant OSM or stably transfected to overexpress human OSM, (3) murine HCC xenografts, and (4) a murine NASH‐related model of hepatic carcinogenesis. OSM was found to be selectively overexpressed in HCC cells of NAFLD/NASH patients, depending on tumor grade. OSM serum levels, barely detectable in patients with simple steatosis or NASH, were increased in patients with cirrhosis and more evident in those carrying HCC. In this latter group, OSM serum levels were significantly higher in the subjects with intermediate/advanced HCCs and correlated with poor survival. Cell culture experiments indicated that OSM upregulation in hepatic cancer cells contributes to HCC progression by inducing epithelial‐to‐mesenchymal transition and increased invasiveness of cancer cells as well as by inducing angiogenesis, which is of critical relevance. In murine xenografts, OSM overexpression was associated with slower tumor growth but an increased rate of lung metastases. Overexpression of OSM and its positive correlation with the angiogenic switch were also confirmed in a murine model of NAFLD/NASH‐related hepatocarcinogenesis. Consistent with this, analysis of liver specimens from human NASH‐related HCCs with vascular invasion showed that OSM was expressed by liver cancer cells invading hepatic vessels. In conclusion, OSM upregulation appears to be a specific feature of HCC arising on a NAFLD/NASH background, and it correlates with clinical parameters and disease outcome. Our data highlight a novel pro‐carcinogenic contribution for OSM in NAFLD/NASH, suggesting a role of this factor as a prognostic marker and a putative potential target for therapy. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Phospho-Smad3 signaling is predictive biomarker for hepatocellular carcinoma risk assessment in primary biliary cholangitis patients.

Patients with primary biliary cholangitis (PBC) are at increased risk for development of hepatocellular carcinoma (HCC), particularly in the presence of comorbidities such as excessive alcohol consumption. Although liver fibrosis is an important risk factor for HCC development, earlier predictors of future HCC development in livers with little fibrosis are needed but not well defined. The transforming growth factor (TGF)-β/Smad signaling pathway participates importantly in hepatic carcinogenesis. Phosphorylated forms (phospho-isoforms) in Smad-related pathways can transmit opposing signals: cytostatic C-terminally-phosphorylated Smad3 (pSmad3C) and carcinogenic linker-phosphorylated Smad3 (pSmad3L) signals. To assess the balance between Smad signals as a biomarker of risk, we immunohistochemically compared Smad domain-specific Smad3 phosphorylation patterns among 52 PBC patients with various stages of fibrosis and 25 non-PBC patients with chronic hepatitis C virus infection. HCC developed in 7 of 11 PBC patients showing high pSmad3L immunoreactivity, but in only 2 of 41 PBC patients with low pSmad3L. In contrast, 9 of 20 PBC patients with minimal Smad3C phosphorylation developed HCC, while HCC did not occur during follow-up in 32 patients who retained hepatic tumor-suppressive pSmad3C. Further, PBC patients whose liver specimens showed high pSmad3L positivity were relatively likely to develop HCC even when little fibrosis was evident. In this study, Smad phospho-isoform status showed promise as a biomarker predicting likelihood of HCC occurrence in PBC. Eventually, therapies to shift favorably Smad phospho-isoforms might decrease likelihood of PBC-related HCC.

Serine palmitoyltransferase long chain subunit 3 is associated with hepatocellular carcinoma in patients with NAFLD.

The prevalence of non-alcoholic fatty liver disease (NAFLD) is continuously increasing, with the proportion of patients with liver carcinogenesis due to non-alcoholic steatohepatitis (NASH) rising accordingly. Although it is important to identify individuals with hepatic carcinogenesis among patients with NAFLD, useful biomarkers have not yet been established. Previously, in a mouse model of diabetes mellitus without genetic modifications, we reported that a high-fat diet increases serine palmitoyltransferase long chain subunit 3 (SPTLC3) expression in liver tissue, accompanied by high frequency of liver carcinogenesis. Serine palmitoyltransferase (SPT) catalyzes the metabolism of fatty acids, particularly sphingolipid synthesis, and SPTLC3 has been identified as its catalytic subunit, but its role in liver disease is unclear. In the present study, the importance of SPTLC3 in NAFLD development was investigated. SPTLC3 mRNA expression was observed in a liver cancer cell line and in liver tissues from patients with NAFLD and liver cancer. In total, 99 patients with NAFLD (66 without hepatocellular carcinoma (HCC) and 33 with HCC were recruited, having been diagnosed by liver biopsy or imaging, along with 6 healthy volunteers (HVs). Serum was collected from patients and HVs, and SPTLC3 level was assessed by ELISA. SPTLC3 expression was higher in non-cancerous compared with that in cancerous liver tissues. Serum SPTLC3 levels were negatively correlated with platelet count and positively correlated with hyaluronic acid levels, suggesting an association with liver fibrosis. Moreover, SPTLC3 levels were significantly higher in the HCC group than in the HV and NAFLD groups. Multivariate analysis of HCC-related factors identified platelets, alanine transferase, albumin and SPTLC3 as independent factors associated with HCC. Furthermore, in patients with other chronic liver diseases (hepatitis B and C, and alcoholic liver disease), no significant differences in serum SPTLC3 levels were observed between patients with or without HCC. Thus, SPTLC3 expression increases specifically with the progression of NAFLD. Overall, the present results indicate that SPTLC3 may be involved in the development of liver carcinogenesis during NAFLD.

Role of Vitamin D as Protective Agent against Induced Liver Damage in Male Rats.

One of the main factors which played a key role in the prevention of liver disorders such as hepatic inflammation, fibrosis, and carcinogenesis would be the vitamin D axis. Therefore, the current research was designed to evaluate the role of Vitamin D (Vit D) as a protective agent against liver damage caused by Thioacetamide (TAA). In the current study, 18 male Wistar rats were randomly allocated into three equal groups (n=6): in group 1(G1) the animals were considered as the control group and did not receive any supplement in drinking water; in group 2 (G2) TAA was administrated to the drinking water at a dose of 300 mg/L; in group 3 (G3) TAA was administrated to the drinking water at a dose of 300 mg/L plus vitamin D at a dose of 0.5 mg/100g body (intraperitoneal) for 8 weeks. At the end of the experiment, the animals were sacrificed and the liver was dissected and removed for histopathology. Histopathological evaluations were used to evaluate the possible adverse effects of TAA on the liver. Several hepatic damages were observed in the G2 group such as lobular disorder, some degrees of degeneration in hepatocytes and enlargement of the hepatic capillaries, and focal necrotic areas. Hepatic fibrosis was observed around portal areas and central veins. Bridging fibrous septa were formed between portal veins. The recorded data in this study showed that Vit D has some beneficial effects in protecting the liver from fibrosis and toxic damages. The recorded data showed that liver damages in the G3 group were partially prevented or cured. In conclusion, it is evident that the Vit D played a pivotal role as an antioxidant and anti-fibrotic agent, therefore it would be the best supplement for liver protection against damages due to toxin entrance into the animal's body.

Pcsk9 Deletion Promotes Murine Nonalcoholic Steatohepatitis and Hepatic Carcinogenesis: Role of Cholesterol.

Proprotein convertase subtilisin/kexin type 9 (Pcsk9) binds to hepatic low‐density lipoprotein receptor (LDLR) and induces its internalization and degradation. Pcsk9 inhibition increases LDLR expression by hepatocytes, which causes increased uptake of circulating LDL, thereby reducing plasma LDL‐cholesterol. However, by increasing the uptake of LDL by the liver, Pcsk9 inhibition increases the exposure of the liver to cholesterol, which may result in higher risk of steatohepatitis and ever carcinogenesis. We compared Pcsk9‐/‐ knockout (KO) mice and appropriate wild‐type (WT) controls of the same strain assigned to a high‐fat (15%, wt/wt) diet for 9 months supplemented with 0.25%, 0.5%, or 0.75% dietary cholesterol. Pcsk9 KO mice on a high‐fat, high‐cholesterol diet exhibited higher levels of hepatic free cholesterol loading and hepatic cholesterol crystallization than their WT counterparts. Pcsk9 KO mice developed crown‐like structures of macrophages surrounding cholesterol crystal‐containing lipid droplets and hepatocytes, exhibited higher levels of apoptosis, and developed significantly more hepatic inflammation and fibrosis consistent with fibrosing steatohepatitis, including 5‐fold and 11‐fold more fibrosis at 0.5% and 0.75% dietary cholesterol, respectively. When injected with diethylnitrosamine, a hepatic carcinogen, early‐in‐life Pcsk9 KO mice were more likely to develop liver cancer than WT mice. Conclusion: Pcsk9 KO mice on high‐cholesterol diets developed increased hepatic free cholesterol and cholesterol crystals and fibrosing steatohepatitis with a higher predisposition to liver cancer compared with WT mice. Future studies should evaluate whether patients on long‐term treatment with anti‐PSCK9 monoclonal antibodies are at increased risk of hepatic steatosis, steatohepatitis or liver cancer, while accounting for concurrent use of statins.

Trefoil factor family 2 inhibits cholangiocarcinogenesis by regulating the PTEN pathway in mice.

Trefoil factor family 2 (TFF2) is one of three trefoil factor family proteins and is expressed abundantly in the gastrointestinal epithelium. Recent studies have shown that TFF2 acts as a tumor suppressor in gastric and pancreatic carcinogenesis; however, little is known about its function in cholangiocarcinogenesis. To investigate the function of TFF2 in cholangiocellular carcinoma (CCC), immunohistochemistry of surgically resected human CCC samples was performed. TFF2 expression was upregulated in the early stage and lost in the late stage of cholangiocarcinogenesis, suggesting the association of TFF2 and CCC. A TFF2 expression vector was then transfected into a CCC cell line (HuCCT1) in vitro, revealing that TFF2 functions as a tumor suppressor not only by inhibiting proliferation and invasion but also by promoting the apoptosis of cancer cells. In addition, PTEN signaling activity was downregulated by TFF2, suggesting an association between TFF2 and PTEN. Next, hepatic carcinogenesis model mice (KC; albumin-Cre/Lox-Stop-Lox KRASG12D) were bred with TFF2-knockout mice to generate a TFF2-deficient mouse model (KC/TFF2-/-). Although the incidence of hepatocellular carcinoma was not different between KC/TFF2-/- mice and control mice, biliary intraepithelial neoplasm (BilIN), the precursor of CCC, was frequently found in the biliary epithelium of KC/TFF2-/- mice. Immunohistochemistry revealed that BilIN samples from these mice did not express PTEN. In addition, two KC/TFF2-/- mice developed CCC adjacent to BilIN, suggesting that TFF2 functions to inhibit the development of CCC in vivo. These results indicate that TFF2 acts as a tumor suppressor to inhibit the development of CCC by regulating PTEN activity.

Persistent mTORC1 activation via Depdc5 deletion results in spontaneous hepatocellular carcinoma but does not exacerbate carcinogen- and high-fat diet-induced hepatic carcinogenesis in mice

The mechanistic target of rapamycin complex 1 (mTORC1) acts as a central regulator of metabolic pathways that drive cellular growth. Abnormal activation of mTORC1 occurs at high frequency in human and mouse hepatocellular carcinoma (HCC). DEP domain-containing protein 5 (DEPDC5), a component of GATOR1 complex, is a repressor of amino acid-sensing branch of the mTORC1 pathway. In the current study, we found that persistent activation of hepatic mTORC1 signaling caused by Depdc5 ablation was sufficient to induce a pathological program of liver damage, inflammation and fibrosis that triggers spontaneous HCC development. Take advantage of the combinatory treatment with a single dose of diethylnitrosamine (DEN) and chronic feeding with high-fat diet (HFD), we demonstrated that hepatic depdc5 deletion did not aggravate DEN&HFD induced liver tumorigenesis, probably due to its protective effects on diet-induced liver steatosis. In addition, we further showed that chronic rapamycin treatment did not have any apparent tumor-suppressing effects on DEN&HFD treated control mice, whereas it dramatically reduced the tumor burden in mice with hepatic Depdc5 ablation. This study provides the novel in vivo evidence for Depdc5 deletion mediated mTORC1 hyperactivation in liver tumorigenesis caused by aging or DEN&HFD treatment. Moreover, our findings also propose that pharmacological inhibition of mTORC1 signaling maybe a promising strategy to treat HCC patients with mutations in DEPDC5 gene.

Risk Factors for Hepatocellular Carcinoma After Splenectomy in Liver Cirrhotic Patients.

Splenectomy is sometimes indicated for portal hypertension caused by cirrhosis, which is a risk for hepatic carcinogenesis. This study aimed to identify risk factors for hepatocellular carcinoma (HCC) development after splenectomy. This retrospective study included 65 patients who underwent splenectomy for portal hypertension between 2009 and 2017. Cox regression analyses were performed to identify factors related to HCC development after splenectomy. The predictive index for HCC development was constructed from the results of multivariate analysis, and 3 risk-dependent groups were defined. Discrimination among the groups was estimated using Kaplan-Meier curves and the log-rank test. Post-splenectomy, 36.9% of patients developed HCC. In the univariate analysis, the etiology of cirrhosis (hepatitis C virus antibody, P = .005, and hepatitis B surface antigen, P = .008, referring to non-B and non-C patients, respectively), presence of HCC history (P < .001), and preoperative hemoglobin level (P = .007) were related to HCC development, and the presence of HCC history (P = .002) and preoperative hemoglobin level (P = .022) were independent risk factors. The predictive index classified three groups at risk; the hazards in each group were significantly different (low vs middle risk, P = .035, and middle vs high risk, P = .011). The etiology of cirrhosis, presence of HCC history, and hemoglobin level were associated with HCC development after splenectomy. The predictive model may aid in HCC surveillance after splenectomy for patients with portal hypertension.

CYP2E1 in Alcoholic and Non-Alcoholic Liver Injury. Roles of ROS, Reactive Intermediates and Lipid Overload.

CYP2E1 is one of the fifty-seven cytochrome P450 genes in the human genome and is highly conserved. CYP2E1 is a unique P450 enzyme because its heme iron is constitutively in the high spin state, allowing direct reduction of, e.g., dioxygen, causing the formation of a variety of reactive oxygen species and reduction of xenobiotics to toxic products. The CYP2E1 enzyme has been the focus of scientific interest due to (i) its important endogenous function in liver homeostasis, (ii) its ability to activate procarcinogens and to convert certain drugs, e.g., paracetamol and anesthetics, to cytotoxic end products, (iii) its unique ability to effectively reduce dioxygen to radical species causing liver injury, (iv) its capability to reduce compounds, often generating radical intermediates of direct toxic or indirect immunotoxic properties and (v) its contribution to the development of alcoholic liver disease, steatosis and NASH. In this overview, we present the discovery of the enzyme and studies in humans, 3D liver systems and genetically modified mice to disclose its function and clinical relevance. Induction of the CYP2E1 enzyme either by alcohol or high-fat diet leads to increased severity of liver pathology and likelihood to develop ALD and NASH, with subsequent influence on the occurrence of hepatocellular cancer. Thus, fat-dependent induction of the enzyme might provide a link between steatosis and fibrosis in the liver. We conclude that CYP2E1 has many important physiological functions and is a key enzyme for hepatic carcinogenesis, drug toxicity and liver disease.

Neonatal streptozotocin treatment rapidly causes different subtype of hepatocellular carcinoma without persistent hyperglycemia in 4CS mice fed on a normal diet

Although diabetes mellitus (DM) is a well-known risk factor for hepatocellular carcinoma (HCC), the underlying mechanisms have not yet to be defined. We previously reported that DIAR mice fed with standard murine diet developed type 1 diabetes and HCC at age of 16 weeks old with a neonatal streptozotocin treatment (n-STZ). Because DIAR mice did not manifest obesity nor develop steatohepatitis, hyperglycemia with streptozotocin trigger or streptozotocin alone might turn on the hepato-carcinogenesis. An insulin-recruitment to DIAR-nSTZ mice showed an increased frequency of HCC during the first 12 weeks of age, although the diabetic indications notably improved. To elucidate the role of hyperglycemia in hepato-carcinogenesis, we performed a head-to-head comparative study by using 4CS mice and DIAR mice with n-STZ treatment. Newborn 4CS mice and DIAR mice were divided into STZ treated group and control group. The blood glucose levels of DIAR-nSTZ mice increased at age of eight weeks, while that of 4CS-nSTZ mice were maintained in the normal range. At eight weeks old, three out of five DIAR-nSTZ mice (60%) and one out of ten 4CS-nSTZ mice (10%) developed multiple liver tumors. At age of 12 weeks old, all eight of DIAR-nSTZ mice (100%) and two of 10 4CS-nSTZ mice (20%) developed multiple liver tumors. At 16 weeks old, all animals of DIAR-nSTZ and 4CS-nSTZ mice occurred liver tumors. DIAR-nSTZ showed hyperglycemia and HCC, and 4CS-nSTZ developed HCC without hyperglycemia. These results were interpreted that the onset of HCC maybe not related to the presence or absence of hyperglycemia but nSTZ treatment. On the other hand, since the carcinogenesis of 4CS-nSTZ is delayed compared to DIAR-nSTZ, hyperglycemia may play a role in the progression of carcinogenesis. Histologically, the liver tumor appeared irregularly trabecular arrangements of hepatocytes with various degrees of nuclear atypia. By immunohistochemical analyses, all liver tumors showed positive staining of glutamine synthetase (GS), an established human HCC marker. The expression pattern of GS was divided into a strong diffuse pattern and weak patchy pattern, respectively. The liver tumor showing the weak GS-patchy pattern expressed biliary/stem markers, EpCAM, and SALL4, partially. Because 4CS-nSTZ mice did not show any metabolic complications such as gaining body weight or high blood glucose level, it is a unique animal model with a simple condition to investigate hepatic carcinogenesis by excluding other factors.

Hepatocellular Carcinoma Immunotherapy and the Potential Influence of Gut Microbiome.

Disruptions in the human gut microbiome have been associated with a cycle of hepatocyte injury and regeneration characteristic of chronic liver disease. Evidence suggests that the gut microbiota can promote the development of hepatocellular carcinoma through the persistence of this inflammation by inducing genetic and epigenetic changes leading to cancer. As the gut microbiome is known for its effect on host metabolism and immune response, it comes as no surprise that the gut microbiome may have a role in the response to therapeutic strategies such as immunotherapy and chemotherapy for liver cancer. Gut microbiota may influence the efficacy of immunotherapy by regulating the responses to immune checkpoint inhibitors in patients with hepatocellular carcinoma. Here, we review the mechanisms by which gut microbiota influences hepatic carcinogenesis, the immune checkpoint inhibitors currently being used to treat hepatocellular carcinoma, as well as summarize the current findings to support the potential critical role of gut microbiome in hepatocellular carcinoma (HCC) immunotherapy.

Liver Field during Immunotherapy of Hepatocellular Carcinoma: Some Like It Hot

Liver Field during Immunotherapy of Hepatocellular Carcinoma: Some Like It Hot

Omics-Based Identification of Shared and Gender Disparity Routes in Hras12V-Induced Hepatocarcinogenesis: An Important Role for Dlk1-Dio3 Genomic Imprinting Region.

The phenomenon of gender disparity is very profound in hepatocellular carcinoma (HCC). Although previous research has revealed important roles of microRNA (miRNA) in HCC, there are no studies investigating the role of miRNAs in gender disparity observed hepatocarcinogenesis. In the present study, we investigated the global miRNAomics changes related to Ras-induced male-prevalent hepatocarcinogenesis in a Hras12V-transgenic mouse model (Ras-Tg) by next-generation sequencing (NGS). We identified shared by also unique changes in miRNA expression profiles in gender-dependent hepatocarcinogenesis. Two hundred sixty-four differentially expressed miRNAs (DEMIRs) with q value ≤0.05 and fold change ≥2 were identified. A vertical comparison revealed that the lower numbers of DEMIRs in the hepatic tumor (T) compared with the peri-tumor precancerous tissue (P) of Ras-Tg and normal liver tissue of wild-type C57BL/6J mice (W) in males indicated that males are more susceptible to develop HCC. The expression pattern analysis revealed 43 common HCC-related miRNAs and 4 Ras-positive-related miRNAs between males and females. By integrating the mRNA transcriptomic data and using 3-node FFL analysis, a group of significant components commonly contributing to HCC between sexes were filtered out. A horizontal comparison showed that the majority of DEMIRs are located in the Dlk1-Dio3 genomic imprinting region (GIR) and that they are closely related to not only hepatic tumorigenesis but also to gender disparity in hepatocarcinogenesis. This is achieved by regulating multiple metabolic pathways, including retinol, bile acid, and steroid hormones. In conclusion, the identification of shared and gender-dependent DEMIRs in hepatocarcinogenesis provides valuable insights into the mechanisms that contribute to male-biased Ras-induced hepatic carcinogenesis.

Identification of Key Genes for Hepatitis Delta Virus-Related Hepatocellular Carcinoma by Bioinformatics Analysis.

It has been proposed that hepatitis delta virus (HDV) induces hepatic carcinogenesis by distinct molecular events compared with hepatocellular carcinoma (HCC) that is commonly induced by other hepatitis viruses. This study aimed to explore the underlying mechanism by identifying the key genes for HDV-HCC using bioinformatics analysis. The GSE107170 dataset was downloaded and the differentially expressed genes (DEGs) were obtained by the online tool GEO2R. Gene otology (GO) functional analyses and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using R packages. The protein-protein interaction (PPI) network was constructed by Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). Hub genes were selected by Cytoscape software according to degree algorithm. The hub genes were further validated in terms of expression and survival analysis based on public databases. A total of 93 commonly upregulated genes and 36 commonly downregulated genes were found. The top 5 upregulated hub genes were TFRC, ACTR2, ARPC1A, ARPC3, and ARPC2. The top 5 downregulated hub genes were CTNNB1, CCND1, CDKN1B, CDK4, and CDKN1A. In the validation analysis, the expressions of ARPC1A, ARPC3, and CDK4 were promoted in general liver cancer samples. Higher expressions of ARPC2 and CDK4 and lower expressions of CDKN1A, CCND1, and CDKN1B were associated with worse prognosis in general HCC patients. The present study identifies a series of key genes that may be involved in the carcinogenesis of HDV-HCC and used as prognostic factors.

Hepatic stellate cells - from past till present: morphology, human markers, human cell lines, behavior in normal and liver pathology.

Hepatic stellate cell (HSC), initially analyzed by von Kupffer, in 1876, revealed to be an extraordinary mesenchymal cell, essential for both hepatocellular function and lesions, being the hallmark of hepatic fibrogenesis and carcinogenesis. Apart from their implications in hepatic injury, HSCs play a vital role in liver development and regeneration, xenobiotic response, intermediate metabolism, and regulation of immune response. In this review, we discuss the current state of knowledge regarding HSCs morphology, human HSCs markers and human HSC cell lines. We also summarize the latest findings concerning their roles in normal and liver pathology, focusing on their impact in fibrogenesis, chronic viral hepatitis and liver tumors.

BIR repeat-containing ubiquitin conjugating enzyme (BRUCE) regulation of β-catenin signaling in the progression of drug-induced hepatic fibrosis and carcinogenesis.

BACKGROUNDBIR repeat-containing ubiquitin conjugating enzyme (BRUCE) is a liver tumor suppressor, which is downregulated in a large number of patients with liver diseases. BRUCE facilitates DNA damage repair to protect the mouse liver against the hepatocarcinogen diethylnitrosamine (DEN)-dependent acute liver injury and carcinogenesis. While there exists an established pathologic connection between fibrosis and hepatocellular carcinoma (HCC), DEN exposure alone does not induce robust hepatic fibrosis. Further studies are warranted to identify new suppressive mechanisms contributing to DEN-induced fibrosis and HCC. AIMTo investigate the suppressive mechanisms of BRUCE in hepatic fibrosis and HCC development.METHODSMale C57/BL6/J control mice [loxp/Loxp; albumin-cre (Alb-cre)-] and BRUCE Alb-Cre KO mice (loxp/Loxp; Alb-Cre+) were injected with a single dose of DEN at postnatal day 15 and sacrificed at different time points to examine liver disease progression. RESULTSBy using a liver-specific BRUCE knockout (LKO) mouse model, we found that BRUCE deficiency, in conjunction with DEN exposure, induced hepatic fibrosis in both premalignant as well as malignant stages, thus recapitulating the chronic fibrosis background often observed in HCC patients. Activated in fibrosis and HCC, β-catenin activity depends on its stabilization and subsequent translocation to the nucleus. Interestingly, we observed that livers from BRUCE KO mice demonstrated an increased nuclear accumulation and elevated activity of β-catenin in the three stages of carcinogenesis: Pre-malignancy, tumor initiation, and HCC. This suggests that BRUCE negatively regulates β-catenin activity during liver disease progression. β-catenin can be activated by phosphorylation by protein kinases, such as protein kinase A (PKA), which phosphorylates it at Ser-675 (pSer-675-β-catenin). Mechanistically, BRUCE and PKA were colocalized in the cytoplasm of hepatocytes where PKA activity is maintained at the basal level. However, in BRUCE deficient mouse livers or a human liver cancer cell line, both PKA activity and pSer-675-β-catenin levels were observed to be elevated.CONCLUSIONOur data support a “BRUCE-PKA-β-catenin” signaling axis in the mouse liver. The BRUCE interaction with PKA in hepatocytes suppresses PKA-dependent phosphorylation and activation of β-catenin. This study implicates BRUCE as a novel negative regulator of both PKA and β-catenin in chronic liver disease progression. Furthermore, BRUCE-liver specific KO mice serve as a promising model for understanding hepatic fibrosis and HCC in patients with aberrant activation of PKA and β-catenin.

Hepatocyte ploidy in cats with and without hepatocellular carcinoma

BackgroundDomestic cats rarely develop hepatocellular carcinoma. The reason for the low prevalence is unknown. Reductions in hepatocellular ploidy have been associated with hepatic carcinogenesis. Recent work in mice has shown that livers with more polyploid hepatocytes are protected against the development of hepatocellular carcinoma. Hepatocyte ploidy in the domestic cat has not been evaluated. We hypothesized that ploidy would be reduced in peri-tumoral and neoplastic hepatocytes compared to normal feline hepatocytes. Using integrated fluorescence microscopy, we quantified the spectra of ploidy in hepatocellular carcinoma and healthy control tissue from paraffin embedded tissue sections.ResultsFeline hepatocytes are predominantly mononuclear and the number of nuclei per hepatocyte did not differ significantly between groups. Normal cats have a greater number of tetraploid hepatocytes than cats with hepatocellular carcinoma.ConclusionsTotal hepatocellular polyploidy in normal cat liver is consistent with values reported in humans, yet cellular ploidy (nuclei per cell) is greater in humans than in cats. Tetraploid cat hepatocytes are predominantly mononuclear.