Pirfenidone Reverts Global DNA Hypomethylation, Promoting DNMT1/UHRF/PCNA Coupling Complex in Experimental Hepatocarcinoma.

Hepatocellular carcinoma (HCC) development is associated with altered modifications in DNA methylation, changing transcriptional regulation. Emerging evidence indicates that DNA methyltransferase 1 (DNMT1) plays a key role in the carcinogenesis process. This study aimed to investigate how pirfenidone (PFD) modifies this pathway and the effect generated by the association between c-Myc expression and DNMT1 activation. Rats F344 were used for HCC development using 50 mg/kg of diethylnitrosamine (DEN) and 25 mg/kg of 2-Acetylaminofluorene (2-AAF). The HCC/PFD group received simultaneous doses of 300 mg/kg of PFD. All treatments lasted 12 weeks. On the other hand, HepG2 cells were used to evaluate the effects of PFD in restoring DNA methylation in the presence of the inhibitor 5-Aza. Histopathological, biochemical, immunohistochemical, and western blot analysis were carried out and our findings showed that PFD treatment reduced the amount and size of tumors along with decreased Glipican-3, ß-catenin, and c-Myc expression in nuclear fractions. Also, this treatment improved lipid metabolism by modulating PPARγ and SREBP1 signaling. Interestingly, PFD augmented DNMT1 and DNMT3a protein expression, which restores global methylation, both in our in vivo and in vitro models. In conclusion, our results suggest that PFD could slow down HCC development by controlling DNA methylation.

Integrating Network Pharmacology and Experimental Validation to Decipher the Mechanism of Action of Astragalus-Atractylodes Herb Pair in Treating Hepatocellular Carcinoma.

Purpose: Traditional Chinese medicine (TCM) therapy is an important means to treat hepatocellular carcinoma (HCC), Astragalus (Latin name: Hedysarum Multijugum Maxim; Chinese name: Huangqi, HQ) and Atractylodes (Latin name: Atractylodes Macrocephala Koidz; Chinese name: Baizhu, BZ) (HQBZ), a classic herb pair, is often used in combination to HCC. However, the main components and potential mechanisms of HQBZ therapy in HCC remain unclear. This study aimed to identify the potential active ingredients and molecular mechanisms of action of HQBZ in HCC treatment. Methods: The HQBZ-Compound-Target-HCC network and HQBZ-HCC transcriptional regulatory network were constructed to screen the core active compound components and targets of HQBZ therapy for HCC. Molecular docking techniques are used to verify the stability of binding core active compound components to targets. GO and KEGG enrichment analysis were used to explore the signaling pathway of HQBZ in HCC treatment, the mechanism of HQBZ treatment of HCC was verified based on in vivo H22 tumor bearing mice and in vitro cell experiments. Results: Network pharmacology and molecular docking studies showed that HQBZ treatment of HCC was related to the targeted regulation of IL-6 and STAT3 by the active compound biatractylolide, KEGG pathway enrichment analysis suggest that HQBZ may play a role in the treatment of HCC through IL-6/STAT3 signaling pathway. In vitro experiment results proved that HQBZ could regulate IL-6/STAT3 signaling pathway transduction on CD8+T cells, inhibit CD8+T cell exhaustion and restore the function of exhausted CD8+T cells. In vivo experiment results proved that HQBZ can regulate IL-6/STAT3 signaling pathway transduction in H22 liver cancer model mouse tumor tissue, increased the proportion of tumor infiltrating CD8+T cells. Conclusion: This study found that HQBZ may play a therapeutic role in HCC by targeting IL-6 and STAT3 through biatractylolide, its mechanism of action is related to regulating IL-6/STAT3 signaling pathway, reversing T cell failure and increasing tumor infiltration CD8+T cells.

Gypenoside L inhibits hepatocellular carcinoma by targeting the SREBP2-HMGCS1 axis and enhancing immune response.

Hepatocellular carcinoma (HCC) is a malignant tumor that occurs in the liver, with a high degree of malignancy and relatively poor prognosis. Gypenoside L has inhibitory effects on liver cancer cells. However, its mechanism of action is still unclear. This study aims to investigate the inhibitory effects of gypenoside L on HCC in vitro and in vivo, and explore its potential mechanisms. The results showed that gypenoside L reduced the cholesterol and triglyceride content in HepG2 and Huh-7 cells, inhibited cell proliferation, invasion and metastasis, arrested cell cycle at G0/G1 phase, promoted cell apoptosis. Mechanistically, it targeted the transcription factor SREPB2 to inhibit the expression of HMGCS1 protein and inhibited the downstream proteins HMGCR and MVK, thereby regulating the mevalonate (MVA) pathway. Overexpression HMGCS1 led to significant alterations in the cholesterol metabolism pathway of HCC, which mediated HCC cell proliferation and conferred resistance to the therapeutic effect of gypenoside L. In vivo, gypenoside L effectively suppressed HCC growth in tumor-bearing mice by reducing cholesterol production, exhibiting favorable safety profiles and minimal toxic side effects. Gypenoside L modulated cholesterol homeostasis, enhanced expression of inflammatory factors by regulating MHC I pathway-related proteins to augment anticancer immune responses. Clinical samples from HCC patients also exhibited high expression levels of MVA pathway-related genes in tumor tissues. These findings highlight gypenoside L as a promising agent for targeting cholesterol metabolism in HCC while emphasizing the effectiveness of regulating the SREBP2-HMGCS1 axis as a therapeutic strategy.

Pregnane X receptor (PXR) deficiency promotes hepatocarcinogenesis via induction of Akr1c18 expression and prostaglandin F2α (PGF2α) levels.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Pregnane X receptor (PXR), a xenobiotic-sensing nuclear receptor, plays a critical role in the metabolism of endogenous and exogenous substances in the liver. Here, we investigate whether PXR plays a role in pathogenesis of HCC. We show that liver tumors were developed in diethylnitrosamine (DEN)-treated in PXR knockout (KO) mice. Hepatic levels of prostaglandin F2α (PGF2α) and aldo-keto reductase family 1 member C18 (Akr1c18), a prostaglandin synthase of catalyzing reduction of PGH2 to PGF2α, were significantly elevated in DEN-treated PXR KO mice. Hepatic mRNA levels of alpha fetoprotein (AFP), cyclin D1 (Ccnd1), fibroblast growth factor 21 (FGF21), and inflammatory cytokine interleukin 6 (IL-6) were significantly increased in DEN-treated PXR KO mice. Other members of Akr1c family, liver metabolizing enzymes including Cyp1a2, Cyp2b10 and Cyp3a11, and bile acid synthesis enzyme Cyp7a1 mRNA levels were significantly decreased in DEN-treated PXR KO mice. Our findings revealed that PXR deficiency promoted DEN-induced HCC in mice via induction of Akr1c18 expression and PGF2α levels and the increased PGF2α levels synthetized by Akr1c18 enhanced hepatocytes proliferation and induced inflammatory cytokine production, which accelerated liver tumor development after DEN treatment, suggesting that PXR deficiency may create a microenvironment that is more prone to DEN-induced liver tumors and targeting PXR and Akr1c18 to reduce PGF2α biosynthesis may be a potential and novel therapeutic strategy for HCC.

Mode of action analysis for fluxapyroxad-induced rat liver tumour formation: evidence for activation of the constitutive androstane receptor and assessment of human relevance.

The fungicide fluxapyroxad (BAS 700 F) has been shown to significantly increase the incidence of liver tumours in male Wistar rats at dietary levels of 1500 and 3000 ppm and in female rats at a dietary level of 3000 ppm via a non-genotoxic mechanism. In order to elucidate the mode of action (MOA) for fluxapyroxad-induced rat liver tumour formation a series of in vivo and in vitro investigative studies were undertaken. The treatment of male and female Wistar rats with diets containing 0 (control), 50, 250, 1500 and 3000 ppm fluxapyroxad for 1, 3, 7 and 14 days resulted in a dose-dependent increases in relative weight at 1500 and 3000 ppm from day 3 onwards in both sexes, with an increase in relative liver weight being also observed in male rats given 250 ppm fluxapyroxad for 14 days. Examination of liver sections revealed a centrilobular hepatocyte hypertrophy in some fluxapyroxad treated male and female rats. Hepatocyte replicative DNA synthesis (RDS) was significantly increased in male rats given 1500 and 3000 ppm fluxapyroxad for 3 and 7 days and in female rats given 50-3000 ppm fluxapyroxad for 7 days and 250-3000 ppm fluxapyroxad for 3 and 14 days; the maximal increases in RDS in both sexes being observed after 7 days treatment. The treatment of male and female Wistar rats with 250-3000 ppm fluxapyroxad for 14 days resulted in significant increases in hepatic microsomal total cytochrome P450 (CYP) content and CYP2B subfamily-dependent enzyme activities. Male Wistar rat hepatocytes were treated with control medium and medium containing 1-100 µM fluxapyroxad or 500 µM sodium phenobarbital (NaPB) for 4 days. Treatment with fluxapyroxad and NaPB increased CYP2B and CYP3A enzyme activities and mRNA levels but had little effect on markers of CYP1A and CYP4A subfamily enzymes and of the peroxisomal fatty acid ß-oxidation cycle. Hepatocyte RDS was significantly increased by treatment with fluxapyroxad, NaPB and 25 ng/ml epidermal growth factor (EGF). The treatment of hepatocytes from two male human donors with 1-100 µM fluxapyroxad or 500 µM NaPB for 4 days resulted in some increases in CYP2B and CYP3A enzyme activities and CYP mRNA levels but had no effect on hepatocyte RDS, whereas treatment with EGF resulted in significant increase in RDS in both human hepatocyte preparations. Hepatocytes from male Sprague-Dawley wild type (WT) and constitutive androstane receptor (CAR) knockout (CAR KO) rats were treated with control medium and medium containing 1-16 µM fluxapyroxad or 500 µM NaPB for 4 days. While both fluxapyroxad and NaPB increased CYP2B enzyme activities and mRNA levels in WT hepatocytes, only minor effects were observed in CAR KO rat hepatocytes. Treatment with both fluxapyroxad and NaPB only increased RDS in WT and not in CAR KO rat hepatocytes, whereas treatment with EGF increased RDS in both WT and CAR KO rat hepatocytes. In conclusion, a series of in vivo and in vitro investigative studies have demonstrated that fluxapyroxad is a CAR activator in rat liver, with similar properties to the prototypical CAR activator phenobarbital. A robust MOA for fluxapyroxad-induced rat liver tumour formation has been established. Based on the lack of effect of fluxapyroxad on RDS in human hepatocytes, it is considered that the MOA for fluxapyroxad-induced liver tumour formation is qualitatively not plausible for humans.

H-ras-targeted genetic therapy remarkably surpassed docetaxel treatment in inhibiting chemically induced hepatic tumors in rats.

AIMS: Hepatocellular carcinoma (HCC) is still a leading cause of cancer-related death worldwide. But its chemotherapeutic options are far from expectation. We here compared H-ras targeted genetic therapy to a commercial docetaxel formulation (DXT) in inhibiting HCC in rats. MAIN METHODS: After the physicochemical characterization of phosphorothioate-antisense oligomer (PS-ASO) against H-ras mutated gene, the PS-ASO-mediated in vitro hemolysis, in vivo hepatic uptake, its pharmacokinetic profile, tissue distribution in some highly perfused organs, its effect in normal rats, antineoplastic efficacy in carcinogen-induced HCC in rats were evaluated and compared against DXT treatment. Mutated H-ras expression by in situ hybridization, hep-par-I, CK-7, CD-15, p53 expression patterns by immunohistochemical methods, scanning electron microscopic evaluation of hepatic architecture, various hepatic marker enzyme levels and caspase-3/9 apoptotic enzyme activities were also carried out in the experimental rats. KEY FINDINGS: PS-ASO showed low in vitro hemolysis (<3 %), and had a sustained PS-ASO blood residence time in vivo compared to DTX, with a time-dependent hepatic uptake. It showed no toxic manifestations in normal rats. PS-ASO distribution was although initially less in the lung than liver and kidney, but at 8 h it accumulated more in lung than kidney. Antineoplastic potential of PS-ASO (treated for 6 weeks) excelled in inhibiting chemically induced tumorigenesis compared to DTX in rats, by inhibiting H-ras gene expression, some immonohistochemical modulations, and inducing caspase-3/9-mediated apoptosis. It prevented HCC-mediated lung metastatic tumor in the experimental rats. SIGNIFICANCE: PS-ASO genetic therapy showed potential to inhibit HCC far more effectively than DXT in rats.

Validation of Core Ingredients and Molecular Mechanism of Cinobufotalin Injection Against Liver Cancer.

Purpose: Cinobufotalin injection has obvious curative effects on liver cancer patients with less toxicity and fewer side effects than other therapeutic approaches. However, the core ingredients and mechanism underlying these anti-liver cancer effects have not been fully clarified due to its complex composition. Methods: Multidimensional network analysis was used to screen the core ingredients, key targets and pathways underlying the therapeutic effects of cinobufotalin injection on liver cancer, and in vitro and in vivo experiments were performed to confirm the findings. Results: By construction of ingredient networks and integrated analysis, eight core ingredients and ten key targets were finally identified in cinobufotalin injection, and all of the core ingredients are tightly linked with the key targets, and these key targets are highly associated with the cell cycle-related pathways, supporting that both cinobufotalin injection and its core ingredients exert anti-liver cancer roles by blocking cell cycle-related pathways. Moreover, in vitro and in vivo experiments confirmed that either cinobufotalin injection or one of its core ingredients, cinobufagin, significantly inhibited cell proliferation, colony formation, cell cycle progression and xenograft tumor growth, and the key target molecules involved in the cell cycle pathway such as CDK1, CDK4, CCNB1, CHEK1 and CCNE1, exhibit consistent changes in expression after treatment with cinobufotalin injection or cinobufagin. Interestingly, some key targets CDK1, CDK4, PLK1, CHEK1, TTK were predicted to bind with multiple of core ingredients of cinobufotalin injection, and the affinity between one of the critical ingredients cinobufagin and key target CDK1 was further confirmed by SPR assay. Conclusion: Cinobufotalin injection was confirmed to includes eight core ingredients, and they play therapeutic effects in liver cancer by blocking cell cycle-related pathways, which provides important insights for the mechanism of cinobufotalin injection antagonizing liver cancer and the development of novel small molecule anti-cancer drugs.

Integration of Ethanol and the Immune Modulator Curcumin for Immunoablation of Hepatocellular Carcinoma.

PURPOSE: To investigate immuno-ethanol ablation using an ethanol and immune adjuvant formulation as a potent immunoablation approach that can achieve an enhanced anticancer effect in the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Ethanol concentration- and exposure time-dependent cellular responses were investigated. Curcumin was combined with ethanol as an immunoablation agent. Cellular uptake of curcumin, cancer cell killing, and inflammatory markers of ethanol-curcumin treatment were characterized. To evaluate the potential in vivo anticancer immunity of ethanol-curcumin treatment, each right and left lobe of rat liver was concurrently inoculated with N1S1 HCC cells and a mixture of treated N1S1 cells (ethanol only or ethanol-curcumin) in Sprague Dawley rats (each group: 5 rats; control: nontreated N1S1 cells). Tumor growth and immune response were characterized with 7T magnetic resonance (MR) imaging, flow cytometry analysis, and immunohistology. RESULTS: An optimized ethanol-curcumin (10% ethanol and 0.5% weight/volume (w/v) curcumin solution) treatment contributed to an enhanced cellular uptake of curcumin, increased cancer cell killing, and decreased inflammatory reaction. Ethanol-curcumin-treated N1S1 cell implantation in the rat liver demonstrated N1S1 HCC tumor rejection. The secondary tumor growth by nontreated N1S1 cell inoculation was significantly suppressed at the same time. Activated anticancer immunity was evidenced by significantly increased CD8+ T cell infiltration (3.5-fold) and CD8+-to-regulatory T cell ratio (4.5-fold) in the experimental group compared with those in the control group. CONCLUSIONS: Enhanced anticancer effect of immuno-ethanol ablation could be achieved with ethanol-curcumin agent. The results underscore the importance of optimized immunoablation therapeutic procedures for enhanced therapeutic outcomes.

Anticancer effect of propranolol on diethylnitrosamine-induced hepatocellular carcinoma rat model.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most widespread type of primary liver cancer. Diethylnitrosamine (DEN), a hepatotoxic hepatocarcinogenic compound, is used to induce HCC in animal models. The non-selective ß-blocker propranolol demonstrated antiproliferative activity in many cancer types. OBJECTIVE: This investigation aimed to evaluate the anticancer effect of propranolol against DEN-induced HCC in rats. METHODS: Thirty adult male rats were divided into the following groups: Group I (C, control), Group II (HCC); received DEN, 70 mg/kg body weight (b.wt.) once a week for 10 weeks, to induce HCC, and Group III (HCC/Prop); received DEN for 10 weeks for HCC induction, then received 20 mg/kg b.wt. propranolol, intraperitoneally for four successive weeks. RESULTS: HCC was developed in rats' livers and confirmed via significant liver architecture changes, significantly elevated activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST), α-fetoprotein (AFP), total- and direct-bilirubin (Bil), and a decline in albumin (ALB) level in serum. HCC group demonstrated elevated levels of malondialdehyde (MDA), nitric oxide (NO), HIF-1α, IL-8, NF-κB, PGE2, TGF-ß1, VEGF, and CD8, but significant decline of GSH, and IL-10 level, with suppression of the antioxidant enzymes' activities. In addition, the gene expression of the hepatic inducible nitric oxide synthase (iNOS), and LAG-3 were up-regulated. Moreover, the protein expression of p-PKC was up-regulated, while that of PD-1 and PD-L1 were down-regulated in the liver tissues of the HCC group. However, propranolol ameliorated the investigated parameters in the HCC/Prop group. CONCLUSION: Propranolol exhibited an anticancer effect and thus can be considered as a promising treatment for HCC. Blocking of PD-1/PD-L1 and LAG-3 signals participated in the anti-tumor effect of propranolol on HCC.

Chronic Administration of Diethylnitrosamine and 2-Acetylaminofluorene Induces Hepatocellular Carcinoma in Wistar Rats.

This study aimed to analyze the biochemical, histological, and gene expression alterations produced in a hepatocarcinogenesis model induced by the chronic administration of diethylnitrosamine (DEN) and 2-acetylaminofluorene (2-AAF) in Wistar rats. Thirteen rats weighing 180 to 200 g were divided into two groups: control and treated. Rats in the treated group were administered an intraperitoneal (i.p.) injection of DEN (50 mg/kg/week) and an intragastric (i.g.) dose of 2-AAF (25 mg/kg/week) for 18 weeks. The treated group had significant increases in their total cholesterol, HDL-C, AST, ALT, ALKP, and GGT levels. Furthermore, a histological analysis showed the loss of normal liver architecture with nuclear pleomorphism in the hepatocytes, atypical mitosis, and fibrous septa that were distributed between the portal triads and collagen fibers through the hepatic sinusoids. The gene expressions of 24 genes related to fibrosis, inflammation, apoptosis, cell growth, angiogenesis, lipid metabolism, and alpha-fetoprotein (AFP) were analyzed; only TGFß, COL1α1, CYP2E1, CAT, SOD, IL6, TNF-α, and ALB showed significant differences when both groups were compared. Additionally, lung histopathological alterations were found in the treated group, suggesting metastasis. In this model, the chronic administration of DEN+2-AAF induces characteristic alterations of hepatocellular carcinoma in Wistar rats without AFP gene expression changes, highlighting different signatures in hepatocellular carcinoma heterogeneity.

The anticarcinogenic effect of eugenol on lung cancer induced by diethylnitrosamine/2-acetylaminofluorene in Wistar rats: insight on the mechanisms of action.

This study was designed to assess the ameliorative effects of eugenol and to propose the possible mechanisms of action of eugenol in diethylnitrosamine (DENA)/acetylaminofluorene (AAF)-caused lung cancer in Wistar rats. To induce lung cancer, DENA at a dose of 150 mg/kg body weight (b.wt) for 2 weeks were intraperitoneally injected once each week and AAF was administered orally at a dose of 20 mg/kg b.wt. four times each week for the next 3 weeks. DENA/AAF-administered rats were orally supplemented with eugenol at a dose of 20 mg/kg b.wt administered once a day until 17 weeks starting from the 1st week of DENA administration. Lung histological lesions, including sheets of tumor cells, micropapillary adenocarcinoma, and apoptotic cells, resulting from the DENA/AAF dosage, were ameliorated by eugenol treatment. However, a significant drop in the levels of LPO in the lungs and a remarkable rise in GSH content and GPx and SOD activities were observed in DENA/AAF-administered rats treated with eugenol compared with those in DENA/AAF-administered controls. Moreover, in DENA/AAF-administered rats, eugenol supplementation significantly reduced TNF-α and IL-1ß levels and mRNA expression levels of NF-κB, NF-κB p65, and MCP-1 but significantly elevated the level of Nrf2. Furthermore, the DENA/AAF-administered rats treated with eugenol exhibited a significant downregulation of Bcl-2 expression levels in addition to a significant upregulation in P53 and Bax expression levels. Otherwise, the administration of DENA/AAF elevated the protein expression level of Ki-67, and this elevation was reversed by eugenol treatment. In conclusion, eugenol has effective antioxidant, anti-inflammatory, proapoptotic, and antiproliferative properties against lung cancer.

Transient Kupffer cell depletion and subsequent replacement by infiltrating monocyte-derived cells does not alter the induction or progression of hepatocellular carcinoma.

Due to a combination of rapid disease progression and the lack of curative treatment options, hepatocellular carcinoma (HCC) is one of the deadliest cancers worldwide. Infiltrated, monocyte-derived, tumor-associated macrophages are known to play a role in HCC pathogenesis, but the involvement of Kupffer cells (KCs) remains elusive. Here, we used the Clec4F-diphteria toxin receptor transgenic mouse model to specifically investigate the effect of KC depletion on HCC initiation, progression and neoplastic growth following liver resection. For this purpose, several HCC mouse models with varying underlying etiologies were used and partial hepatectomy was performed. Our results show that in HCC, developed on a fibrotic or non-alcoholic steatohepatitis background, depletion of embryonic KCs at the onset of HCC induction and the subsequent replacement by monocyte-derived KCs does not affect the tumor burden, tumor microenvironment or the phenotype of isolated KCs at end-stage disease. In non-chronic liver disease-associated diethylnitrosamine-induced HCC, ablation of Clec4F+ KCs did not alter tumor progression or neoplastic growth following liver resection. Our results show that temporal ablation of resident KCs does not impact HCC pathogenesis, neither in the induction phase nor in advanced disease, and indicate that bone marrow-derived KCs are able to swiftly repopulate the available KC niche and adopt their phenotype.

In silico and in vivo hepatoprotective activity of the synthesized 5-benzylidene-2-thiohydantoin against diethylnitrosamine-induced liver injury in a rat model.

In the present study, the hepatoprotective effect of 5-benzylidine-2-thiohydantoin (5B2T), a unique derivative of the thiohydantoin group, on liver injury induced by diethylnitrosamine (DEN) in male rats was investigated. The experimental animals were divided into three groups, each with 14 rats. Rats in group I were considered to be controls and received only 10% Tween 80. Rats in group II were injected with 200 mg/kg DEN intraperitoneally. Rats in group III were injected with a single dose of DEN 200 mg/kg intraperitoneally and received the treatment orally (50 mg/kg, 5B2T) for two durations, 3 and 6 weeks. At the end of the experiment, blood was collected for the analysis of liver function and pro-inflammatory cytokine IL-6 and tumor necrosis factor α (TNF-α) levels. Additionally, liver specimens were used for histopathological examination and immunohistochemistry. The single intraperitoneal injection of 200 mg/kg DEN into rats resulted in significant elevation of serum enzyme levels of AST, ALT and ALP, which are indicators of hepatocellular damage, along with elevation in TNF-α and IL-6 in the DEN group. The results of both LFTs and ELISA in the treatment group showed improvements and a decline in the levels of the markers. Histopathological examination showed fibrosis, necrosis and infiltration of inflammatory cells in the DEN group, with lower intensity in the treatment group. The results of immunohistochemical staining revealed strong positive staining of both HSA and Ki-67 antibodies in the DEN group, with much lower intensity in the treatment group. The results of the docking study indicated that 5B2T has a remarkable interaction with TNF-α (PDB ID: 1TNF) and human IL-6 (PDB ID: 1IL6) with binding site energies of - 7.1 and - 6.1 (kcal/mol), respectively. The correct absorption and binding between the drug and the receptor was evaluated through computerized molecular docking by using the AutoDock program. The conclusion of the results from the current study reflected the interesting hepatoprotective abilities of 5B2T against DEN-induced hepatocellular damage and cancer in experimental rats.

Experimental VX2 Rabbit Liver Tumor Model in Carbon Tetrachloride-Induced Cirrhosis of the Liver.

Liver cirrhosis is a major underlying factor in the development of hepatocellular carcinoma. Currently, there is an unmet need for midsize experimental vertebrate models that would offer reproducible implantable liver tumors in a cirrhotic liver background. This study establishes a protocol for a syngeneic rabbit model of VX2 liver cancer with underlying liver cirrhosis induced using carbon tetrachloride (CCl4). Male New Zealand white rabbits (n = 3) received CCl4 by intragastric administration once weekly. Concentrations started at 5% v/v CCl4 dissolved in olive oil. CCl4 dosing was progressively increased every week by 2.5% v/v increments for the duration of treatment (16 weeks total). VX2 tumors were then orthotopically implanted into the left hepatic lobe and allowed to grow for 3 weeks. Cross-sectional imaging confirmed the presence of hepatic tumors. Gross and histopathological evaluations showed reproducible tumor growth in the presence of liver cirrhosis in all animals.

Modulation of EphA7 and pEphA7 Protein Expression: Potential Biomarkers for Early Detection of Hepatocellular Carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the leading drivers of cancer-related mortality in the world. As a result, researchers are constantly looking for ways to optimize the screening and diagnosis of the said malignancy. OBJECTIVE: To establish the mice model of hepatocellular carcinoma with the administration of a suitable dose of diethylnitrosamine (DEN) and examine the utility of EphA7 and pEphA7 as ideal diagnostic markers in HCC. METHODS: Swiss Albino (BALB/c) mice of around 10-12 weeks old were exposed to a known hepatocarcinogen-diethylnitrosamine at a dose of 20 mg/kg body weight at weekly intervals for a period of 4, 8, 12, & 16 weeks. Blood was collected from mice of different experimental groups, and age-matched control and serum were separated from whole blood samples. The liver homogenate was prepared after completion of treatment, and the resulting supernatant was used for enzyme assays. A range of liver biomarker enzyme assays such as Gamma-glutamyl transpeptidase (GGT), Acetylcholine esterase (AChE), GPx activity and GSH level, Heme oxygenase-1 (HO-1), GPC3 and alpha-fetoprotein (AFP) level along with the expression of Caspase-3, EphA7 and pEphA7 were evaluated. RESULTS: An elevation in body weight and relative liver weight across the treatment period (4, 8, 12, 16 weeks) was observed in DEN-treated mice. Significant differences in GGT levels between control and DEN treated mice were noted in the present study (P < 0.005). In the 16th week of the treatment period, a significant difference in AchE level was noted between the treated and control group (P < 0.001). However, there was no statistically significant difference in the levels of SGOT and SGPT levels between the control and DEN treated groups (P > 0.001). Lower GSH and GPx levels were demonstrated in the treated mice as compared to control over all the treatment period. Loss of Caspase-3 expression and significant differences in expression of HO-1 activity in treated vs. non-treated group of mice were observed. Significant differences in EphA7 and pEphA7 protein expression levels were noted in the DEN-treated vs. control groups across all the treatment periods (4 weeks: P < 0.05; 8 weeks: P < 0.05; 12 weeks:  P < 0.005; 16 weeks: P < 0.05). CONCLUSION: The present study indicated that EphA7 and phosphoEphA7 over-expression might contribute to the malignancy transition, invasion development, and metastasis of HCC. As a result, along with the known markers such as AFP and others, EphA7 and pEphA7 could be a very putative biomarkers of HCC, particularly at a very early stage of cancer development.

Dietary folate drives methionine metabolism to promote cancer development by stabilizing MAT IIA.

Folic acid, served as dietary supplement, is closely linked to one-carbon metabolism and methionine metabolism. Previous clinical evidence indicated that folic acid supplementation displays dual effect on cancer development, promoting or suppressing tumor formation and progression. However, the underlying mechanism remains to be uncovered. Here, we report that high-folate diet significantly promotes cancer development in mice with hepatocellular carcinoma (HCC) induced by DEN/high-fat diet (HFD), simultaneously with increased expression of methionine adenosyltransferase 2A (gene name, MAT2A; protein name, MATIIα), the key enzyme in methionine metabolism, and acceleration of methionine cycle in cancer tissues. In contrast, folate-free diet reduces MATIIα expression and impedes HFD-induced HCC development. Notably, methionine metabolism is dynamically reprogrammed with valosin-containing protein p97/p47 complex-interacting protein (VCIP135) which functions as a deubiquitylating enzyme to bind and stabilize MATIIα in response to folic acid signal. Consistently, upregulation of MATIIα expression is positively correlated with increased VCIP135 protein level in human HCC tissues compared to adjacent tissues. Furthermore, liver-specific knockout of Mat2a remarkably abolishes the advocating effect of folic acid on HFD-induced HCC, demonstrating that the effect of high or free folate-diet on HFD-induced HCC relies on Mat2a. Moreover, folate and multiple intermediate metabolites in one-carbon metabolism are significantly decreased in vivo and in vitro upon Mat2a deletion. Together, folate promotes the integration of methionine and one-carbon metabolism, contributing to HCC development via hijacking MATIIα metabolic pathway. This study provides insight into folate-promoted cancer development, strongly recommending the tailor-made folate supplement guideline for both sub-healthy populations and patients with cancer expressing high level of MATIIα expression.

hnRNPC induces isoform shifts in miR-21-5p leading to cancer development.

MicroRNA (miRNA) processing is a critical step in mature miRNA production. Its dysregulation leads to an increase in miRNA isoforms with heterogenous 5'-ends (isomiRs), which can recognize distinct target sites because of their shifted seed sequence. Although some miRNA genes display productive expression of their 5'-isomiRs in cancers, how their production is controlled and how 5'-isomiRs affect tumor progression have yet to be explored. In this study, based on integrative analyses of high-throughput sequencing data produced by our group and publicly available data, we demonstrate that primary miR-21 (pri-miR-21) is processed into the cancer-specific isomiR isomiR-21-5p | ±1, which suppresses growth hormone receptor (GHR) in liver cancer. Treatment with antagomirs against isomiR-21-5p | ±1 inhibited the in vitro tumorigenesis of liver cancer cells and allowed the recovery of GHR, whereas the introduction of isomiR-21-5p | ±1 mimics attenuated these effects. These effects were validated in a mouse model of spontaneous liver cancer. Heterogeneous nuclear ribonucleoprotein C and U2 small nuclear RNA auxiliary factor 2 were predicted to bind upstream of pre-miR-21 via a poly-(U) motif and influence Drosha processing to induce the production of isomiR-21-5p | ±1. Our findings suggest an oncogenic function for the non-canonical isomiR-21-5p | ±1 in liver cancer, and its production was shown to be regulated by hnRNPC.

Nrf2 activation contributes to hepatic tumor-augmenting effects of developmental arsenic exposure.

Developmental arsenic exposure increases cancer risk in later life with the mechanism elusive. Oxidative stress is a dominant determinant in arsenic toxicity. However, the role of Nrf2, a key regulator in antioxidative response, in tumor-augmenting effects by developmental arsenic exposure is unclear. In the present study, wild-type C57BL/6J and Nrf2-konckout (Nrf2-KO) were developmentally exposed to inorganic arsenic via drinking water. For hepatic tumorigenesis analysis, mice were intraperitoneally injected with diethylnitrosamine (DEN) at two weeks of age. Developmental arsenic exposure aggravated tumor multiplicity and burden, and expression of PCNA and AFP in hepatic tumors induced by DEN. Nrf2 activation as indicated by over-expression of Nrf2 and its downstream genes, including Gss, Gsr, p62, Gclc and Gclm, was found in liver tumors, as well as in the livers in developmentally arsenic-exposed pups at weaning. Notably, Nrf2 deficiency attenuated tumor-augmenting effects and over-expression of Nrf2 downstream genes due to developmental arsenic exposure. Furthermore, the levels of urinary DEN metabolite (acetaldehyde) and hepatic DNA damage markers (O6-ethyl-2-deoxyguanosine adducts and γ-histone H2AX) after DEN treatment were elevated by Nrf2 agonist, 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide. Collectively, our data suggest that augmentation of DEN-induced hepatic tumorigenesis by developmental arsenic exposure is dependent on Nrf2 activation, which may be related to the role of Nrf2 in DEN metabolic activation. Our findings reveal, at least in part, the mechanism underlying increased susceptibility to developing cancer due to developmental arsenic exposure.

The mouse Anxa6/miR-9-5p/Anxa2 axis modulates TGF-ß1-induced mouse hepatic stellate cell (mHSC) activation and CCl4-caused liver fibrosis.

Chronic liver disease such as hepatic fibrosis is a major cause of morbidity and mortality and has been related to high individual risk of hepatocellular carcinoma (HCC). Hepatic stellate cells (HSCs) activation is a central event of hepatic fibrosis progression. In this study, the up-regulation of lncRNA ANXA2P2 (mouse Anxa6) was found in liver fibrosis. Within CCl4-caused liver fibrosis murine model, Anxa6 knockdown partially ameliorated CCl4-induced hepatic fibrosis and blocked the PI3K/Akt signaling activation. In TGF-ß1-stimulated HSCs, Anxa6 knockdown partially inhibited TGF-ß1-induced HSC activation and blocked the PI3K/Akt signaling activation. Mouse Anxa6 downstream mmu-miR-9-5p directly targeted Anxa2; Anxa6 negatively regulated mmu-miR-9-5p, and mmu-miR-9-5p negatively regulated mouse Anxa2. In TGF-ß1-stimulated HSCs, miR-9-5p inhibitor promoted TGF-ß1-induced HSC activation and PI3K/Akt signaling activation, whereas Anxa2 knockdown exerted opposite effects; Anxa2 knockdown significantly attenuated miR-9-5p inhibitor effects upon TGF-ß1-stimulated HSCs. In conclusion, lncRNA ANXA2P2 (mouse Anxa6) expression is up-regulated in hepatic fibrosis and exerts pro-fibrotic effects on CCl4-caused liver fibrosis model mice and TGF-ß1-stimulated HSCs. The mouse Anxa6/miR-9-5p/Anxa2 axis and the PI3K/Akt pathway might participate in the functions of lncRNA ANXA2P2 (mouse Anxa6) on hepatic fibrosis.

Senescence Connects Autophagy Deficiency to Inflammation and Tumor Progression in the Liver.

BACKGROUND & AIMS: Cellular senescence frequently is present in injured livers. The induction mechanism and the pathologic role are not always clear. We aimed to understand the dynamics of senescence induction and progression, and the mechanism responsible for the pathology using a mouse model that disables the essential process of autophagy. METHODS: Mice deficient in key autophagy genes Atg7 or Atg5 in the liver were used. Senescence was measured using established cellular and molecular signatures. The mechanistic roles of nuclear factor erythroid 2 (NRF2), forkhead box K1, and C-C motif chemokine receptor 2 (CCR2) were assessed using mouse genetic models. Liver functions, pathology, and tumor development were measured using biochemical and histologic approaches. RESULTS: Inducible deletion of Atg7 rapidly up-regulated cyclin-dependent kinase inhibitors independently of injury and induced senescence-associated ß-galactosidase activities and senescence-associated secretory phenotype (SASP). Sustained activation of NRF2 was the major factor causing senescence by mediating oxidative DNA damage and up-regulating C-C motif chemokine ligand 2, a key component of autophagy-related SASP, via the NRF2-forkhead box K1 axis. Senescence was responsible for hepatic inflammation through CCR2-mediated recruitment of CD11b+ monocytes and CD3+ T cells. The CCR2-mediated process in turn enhanced senescence and SASP by up-regulating cyclin-dependent kinase inhibitors and chemokines. Thus, senescence and inflammation can mutually augment each other, forming an amplification loop for both events. The CCR2-mediated process also modulated liver injury and tumor progression at the later stage of autophagy deficiency-related pathology. CONCLUSIONS: These results provide the insight that hepatic senescence can occur early in the disease process, triggers inflammation and is enhanced by inflammation, and has long-term effects on liver injury and tumor progression.