Protocatechuic acid as a potent anticarcinogenic compound in purple rice bran against diethylnitrosamine-initiated rat hepatocarcinogenesis.

Our previous study demonstrated that purple rice bran extract (PRBE) could inhibit diethylnitrosamine (DEN)-induced hepatocarcinogenesis. Protocatechuic acid (PCA) is the major phenolic acid contained in the PRBE. Therefore, this study aimed to determine whether PCA is an anticarcinogenic compound in purple rice extract. Rats were intraperitoneally injected with DEN to induce glutathione S-transferase placental form (GST-P)-positive foci. Rats were fed with PRBE at 500 mg kg-1 body weight or PCA at 4 mg kg-1 body weight for 5 and 15 weeks. PCA administration attenuated DEN-induced hepatic GST-P positive foci to a degree similar to PRBE. The molecular mechanisms of PCA in the initiation stage were correlated with reduced activity of cytochrome P450 reductase and induction of glutathione S-transferase. In addition, PCA also downregulated the expression of TNF-α and IL-1ß genes in rat liver. These genes are associated with the inhibition of inflammation. In the promotion stage, PCA suppressed cell proliferation correlated with the downregulation of Cyclin D1 expression. Moreover, it also induced apoptosis, indicated by increased expression of P53 and Bad genes, and decreased the expression of the anti-apoptotic Bcl-xl in DEN-initiated rats. These findings suggest that PCA is an active compound in the anticarcinogenic action of purple rice bran.

Hepatocellular carcinoma induces body mass loss in parallel with osmolyte and water retention in rats.

AIMS: The number of cancer survivors with cardiovascular disease is increasing. However, the effect of cancer on body fluid regulation remains to be clarified. In this study, we evaluated body osmolyte and water imbalance in rats with hepatocellular carcinoma. MAIN METHODS: Wistar rats were administered diethylnitrosamine, a carcinogenic drug, to establish liver cancer. We analyzed tissue osmolyte and water content, and their associations with aldosterone secretion. KEY FINDINGS: Hepatocellular carcinoma rats had significantly reduced body mass and the amount of total body sodium, potassium, and water. However, these rats had significantly increased relative tissue sodium, potassium, and water content per tissue dry weight. Furthermore, these changes in sodium and water balance in hepatocellular carcinoma rats were significantly associated with increased 24-h urinary aldosterone excretion. Supplementation with 0.25% salt in drinking water improved body weight reduction associated with sodium and water retention in hepatocellular carcinoma rats, which was suppressed by treatment with spironolactone, a mineralocorticoid receptor antagonist. Additionally, the urea-driven water conservation system was activated in hepatocellular carcinoma rats. SIGNIFICANCE: These findings suggest that hepatocellular carcinoma induces body mass loss in parallel with activation of the water conservation system including aldosterone secretion and urea accumulation to retain osmolyte and water. The osmolyte and water retention at the tissue level may be a causative factor for ascites and edema formation in liver failure rats.

Kangxianruangan granule­containing serum mediated inhibition of hepatic oval cell differentiation into hepatocellular carcinoma cells via the Wnt­1/ß­catenin signaling pathway.

Hepatocellular carcinoma is a malignancy with poor clinical prognosis. Hepatic oval cells (HOCs) tend to differentiate into cancerous hepatocellular carcinoma cells (HCCs) in the tumor microenvironment. The purpose of the present study was to explore the role of kangxianruangan granule (KXRG)­containing serum in inhibiting the differentiation of HOCs into HCCs via the Wnt­1/ß­catenin signaling pathway. N­methyl­N'­nitro­N­nitrosoguanidine (MNNG) was applied to induce the transformation of the rat HOC cell line WB­F344 into HCCs. The overexpression plasmid, Wnt­1­up, was utilized to increase Wnt­1 expression. Subsequently, high, medium and low concentrations of KXRG were applied to MNNG­treated WB­F344 cells to assess the inhibitory effect of KXRG on cell differentiation. Flow cytometry was conducted to detect the cell cycle distribution, apoptotic rate and expression of cytokeratin­19 (CK­19) protein in cells. An immunofluorescence double staining protocol was used to detect the expression of Wnt­1 and ß­catenin. ELISAs were performed to detect α fetoprotein in the cell supernatants. Reverse transcription­quantitative PCR and western blotting were conducted to detect the mRNA and protein expression levels of Wnt­1, ß­catenin, Cyclin D1, C­myc, matrix metalloproteinase­7 (MMP­7), Axin2 and epithelial cell adhesion molecule (EpCAM) in cells. Compared with the normal group, the apoptotic rate, proportion of S phase cells, concentration of AFP in the cell supernatant, level of CK­19 protein, and mRNA and protein expression levels of Wnt­1, ß­catenin, Cyclin D1, C­myc, MMP­7, Axin2 and EpCAM were all significantly increased in the model group. Addition of KXRG significantly reduced the aforementioned indicators compared with the model group. Moreover, Wnt­1 overexpression further increased the aforementioned indicators compared with the model group, whereas KXRG significantly inhibited these effects. The results indicated that KXRG inhibited the differentiation of HOCs into HCCs via the Wnt­1/ß­catenin signaling pathway, which suggested the potential clinical application of KXRG for the prevention of hepatocellular carcinoma.

Therapeutic Potential of Cucumis melo (L.) Fruit Extract and Its Silver Nanopartciles Against DEN-Induced Hepatocellular Cancer in Rats.

Biosynthesized silver nanoparticles have a wide range of biological activities and using nanoparticles as one of the novel approaches in cancer therapy. In this present research work, the anti-cancer efficacy of Cucumis melo fruit extract and its silver nanoparticles was explored. Wistar rats were divided into six groups and hepatic cancer was induced with 0.01% DEN (diethylnitrosamine) through drinking water for 16 weeks. Cyclophosphamide was given as the standard drug at the dose of 50 mg/kg body weight. Hematological parameters showed a decrease in the levels of hemoglobin (Hb), packed cell volume (PCV), red blood cells (RBC), mean corpuscular volume (MCV), mean corpuscular Hb (MCH), mean corpuscular Hb concentration (MCHC), and platelets (PLTS) levels except white blood cell (WBC) in DEN-induced cancer animals. Significant alterations in the hematological parameters were observed after treatment which indicate the protective effect of Cucumis melo fruit on the hemopoietic system. The structural integrity of the cells has been damaged in cancer-induced animals, and this results in cytoplasmic leakage of enzyme into the blood stream, leads to the elevated levels of these enzymes in blood with subsequent fall in the tissues. Hence, the levels of liver function markers such as AST ALT, ALP, LDH, GGT, and 5'NT were significantly elevated in serum and the liver of cancer-induced rats. The levels of serum tumor markers, viz., alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA), elevated in rats induced with DEN, which then were reduced following Cucumis melo fruit treatment, indicating the anti-cancer activity of the drug. Histological evaluation of the liver and kidney was also performed to authenticate the present work. Treatment with crude extract and silver nanoparticles of Cucumis melo fruit indicates that Cucumis melo fruit could have exerted its protective effect.

A highly selective and potent CXCR4 antagonist for hepatocellular carcinoma treatment.

The CXC chemokine receptor type 4 (CXCR4) receptor and its ligand, CXCL12, are overexpressed in various cancers and mediate tumor progression and hypoxia-mediated resistance to cancer therapy. While CXCR4 antagonists have potential anticancer effects when combined with conventional anticancer drugs, their poor potency against CXCL12/CXCR4 downstream signaling pathways and systemic toxicity had precluded clinical application. Herein, BPRCX807, known as a safe, selective, and potent CXCR4 antagonist, has been designed and experimentally realized. In in vitro and in vivo hepatocellular carcinoma mouse models it can significantly suppress primary tumor growth, prevent distant metastasis/cell migration, reduce angiogenesis, and normalize the immunosuppressive tumor microenvironment by reducing tumor-associated macrophages (TAMs) infiltration, reprogramming TAMs toward an immunostimulatory phenotype and promoting cytotoxic T cell infiltration into tumor. Although BPRCX807 treatment alone prolongs overall survival as effectively as both marketed sorafenib and anti-PD-1, it could synergize with either of them in combination therapy to further extend life expectancy and suppress distant metastasis more significantly.

Relationship between locomotor activity rhythm and corticosterone levels during HCC development, progression, and treatment in a mouse model.

Cancer-related fatigue (CRF) and stress are common symptoms in cancer patients and represent early side effects of cancer treatment which affect the life quality of the patients. CRF may partly depend on disruption of the circadian rhythm. Locomotor activity and corticosterone rhythms are two important circadian outputs which can be used to analyze possible effects on the circadian function during cancer development and treatment. The present study analyzes the relationship between locomotor activity rhythm, corticosterone levels, hepatocellular carcinoma (HCC) development, and radiotherapy treatment in a mouse model. HCC was induced in mice by single injection of diethylnitrosamine (DEN) and chronic treatment of phenobarbital in drinking water. Another group received chronic phenobarbital treatment only. Tumor bearing animals were divided randomly into four groups irradiated at four different Zeitgeber time points. Spontaneous locomotor activity was recorded continuously; serum corticosterone levels and p-ERK immunoreaction in the suprachiasmatic nucleus (SCN) were investigated. Phenobarbital treated mice showed damped corticosterone levels and a less stable 24 hours activity rhythm as well as an increase in activity during the light phase, reminiscent of sleep disruption. The tumor mice showed an increase in corticosterone level during the inactive phase and decreased activity during the dark phase, reminiscent of CRF. After irradiation, corticosterone levels were further increased and locomotor activity rhythms were disrupted. Lowest corticosterone levels were observed after irradiation during the early light phase; thus, this time might be the best to apply radiotherapy in order to minimize side effects.

Vildagliptin, a dipeptidyl peptidase-4 inhibitor, reduces betel-nut induced carcinogenesis in female mice.

AIM: Betel-nut, a popular masticatory among Southeast Asian populations is a class I carcinogen, previously associated with dyslipidemia and aberrant lipid metabolism, and is reported to be used more frequently by females, than males. This study investigates the potential of repurposing the anti-diabetic drug, vildagliptin, a dipeptidyl peptidase-4 inhibitor, for alleviating the oncogenic condition in female Swiss Albino mice administered an aqueous extract of betel-nut (AEBN) orally (2 mg ml-1) for 24 weeks. MAIN METHODS: Tissues were investigated by histopathological, immunohistochemical and apoptosis assays. Biochemical analyses of oxidative stress markers and lipid profile were performed using different tissues and sera. The expressions of different proteins involved in lipid metabolism and oncogenic pathways were evaluated by Western blotting. KEY FINDINGS: AEBN induced carcinogenesis primarily in the liver by significantly impairing AMPK signaling, inducing oxidative stress, activating Akt/mTOR signaling, increasing Ki-67 immunoreactivity and cyclin D1 expression, and significantly diminishing apoptosis. Co-administration of AEBN with vildagliptin (10 mg kg-1 body weight) for 8 weeks reduced liver dysplasia, and significantly decreased free palmitic acid, increased free oleic acid, normalized lipid profile, decreased oxidative stress, cyclin D1 expression, Ki-67 immunoreactivity, and Bcl2 expression, and increased the ratio of apoptotic/non-apoptotic cells. Mechanistically, vildagliptin elicited these physiological and molecular alterations by restoring normal AMPK signaling and reducing the cellular expressions of FASN and HMGCR, restoring AMPK-dependent phosphorylation of p53 at Ser-15 and reducing Akt/mTOR signaling. SIGNIFICANCE: These results indicate that vildagliptin may alleviate betel-nut induced carcinogenesis in the liver of female mice.

Investigation of the Effects of Octreotide Agent on Oxidative Stress, 8-Hydroxy Deoxyguanosine in Experimental Hepatic Carcinogenesis Rat Model.

INTRODUCTION: 2-AAF and DEN are well-known liver toxicants commonly used to stimulate tumors in laboratory animals. AIM: The aim of this study was to investigate the effect of octreotide on DEN-induced and 2-AAF-supplemented hepatocarcinogenesis in Wistar albino rats. MATERIALS AND METHODS: In this study, 64 Wistar albino rats were divided into 8 groups. DEN (175 mg/kg) initiated and 2-AAF (20 mg/kg) promoted liver carcinogenesis in rats. The tumor growth inhibitor octreotide (300 µg/kg) was used. Rats were sacrificed at the end of experiment and their liver tissues were taken for the study. SOD, GSH-Px, CAT activities, NO and MDA levels were measured spectrophotometrically. Also, Hsp70 and 8-OHdG was measured by the ELISA method. RESULTS: In group 7, MDA, 8-OHdG, and Hsp70 levels were significantly increased. In addition, SOD, GSH-Px activity was significantly reduced in this group. MDA, 8-OHdG and Hsp70 levels were significantly reduced in Group 8, which received octreotide for treatment. CONCLUSION: DEN and 2-AAF cause very serious liver damage. Octreotide protects the liver from carcinogenesis, increases the activity of cellular antioxidant enzymes and helps reduce DNA damage. Therefore, octreotide may be an inhibitor in tumor cells and may reduce oxidative stress.

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

The activation of the Wnt/ß-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/ß-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/ß-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/ß-catenin pathway was altered in Diwu Yanggan-treated animals, indicating that the Diwu Yanggan treatment accelerated the activation of the Wnt/ß-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/ß-catenin signaling pathway.

Phytochemicals, antioxidant activity and hepatoprotective effect of ginger (Zingiber officinale) on diethylnitrosamine toxicity in rats.

Context: Chronic liver damage has serious medical consequences. Objective: To investigate the hepatoprotective effect of dry Zingiber officinale (ginger) and its essential (volatile) oil against diethylnitrosamine (DEN) toxicity in rats. Materials and methods: Phenols and flavonoids components were characterized in dry ginger using HPLC-UV instrument while ginger essential oil (E.O.) was investigated via GC-MS technique. Antioxidant activity was determined in vitro. In rat model, ginger was administrated for 2 months. Lipid profile, antioxidant biomarkers, liver functions and histopathology were assessed. Results: Chlorogenic acid (63.85 ppm) and hesperidin (156.91 ppm) are among the major phenolic and flavonoid constituents in dry ginger. Curcumene (15.21%) and linalool (13.47%) represent the main E.O. constituents. In rats treated with ginger E.O., a significant elevation in serum HDL (31.14%) was accompanied by a decrease in LDL (55.14%). A significant decrease in serum ALT and ALP was reported (56.85% and 53.84%, respectively). Serum GSH-Px activity has significantly increased 75.06%. Meanwhile, E.O. showed anticancer potential against HepG2 cell line (IC50 = 40 µg/mL). Liver histopathological examinations confirmed the protective effect against abnormalities. Conclusion: Ginger was able to reduce the severity of DEN-cytotoxicity in rats, which suggests a novel antioxidant role originating from this medicinal plant.

Anticancer effects of echinacoside in hepatocellular carcinoma mouse model and HepG2 cells.

Echinacoside (ECH) is a phenylethanoid glycoside extracted from a Chinese herbal medicine, Cistanches salsa. ECH possesses many biological properties, including anti-inflammation, neural protection, liver protection, and antitumor. In the current study, we aimed to explore the effects of ECH on hepatocellular carcinoma (HCC) and the underlying mechanisms. The results showed that ECH could attenuate diethylnitrosamine (DEN)-induced HCC in mice, and exerted antiproliferative and proapoptotic functions on HepG2 HCC cell line. ECH exposure in HepG2 cells dose-dependently reduced the phosphorylation of AKT (p-AKT) and enhanced the expression of p21 (a cell cycle inhibitor) and Bax (a proapoptotic protein). Furthermore, ECH significantly suppressed insulin-like growth factor-1-induced p-AKT and cell proliferation. These data indicated that phosphoinositide 3-kinase (PI3K)/AKT signaling was involved in the anti-HCC activity of ECH. Gene set enrichment analysis results revealed a positive correlation between the PI3K pathway and triggering receptors expressed on myeloid cells 2 (TREM2) expression in HCC tissues. ECH exposure significantly decreased TREM2 protein levels in HepG2 cells and DEN-induced HCC. Furthermore, ECH-mediated proliferation inhibition and AKT signaling inactivation were notably attenuated by TREM2 overexpression. In conclusion, ECH exerted its antitumor activity via decreasing TREM2 expression and PI3K/AKT signaling.

Protective role of fucoxanthin in diethylnitrosamine-induced hepatocarcinogenesis in experimental adult rats.

Hepatocellular carcinoma (HCC) accounts for majority of cancer related deaths. Two major risk factors in induction of HCC are chemical and virus, however, the possible mechanisms of their differences remain indefinable. The current study focused on protective role of Fucoxanthin (Fx) in liver affected by diethylnitrosamine (DEN)-induced HCC. In this study, levels of liver enzymes, oxidative stressors, antioxidant status, and lipoproteins were compared both in tissue and blood. Tissues were also analyzed extensively by histological studies using H and E staining and transmission electron microscopy (TEM). Rats were clustered into four groups of six experimental animals. Group I: Control rats were administered isotonic saline intraperitoneal Group II: Animals received 0.01% DEN through drinking water to induce hepatocellular carcinoma. Group III: Animals received 0.01% DEN simultaneously oral supplementation of Fx (50 mg/kg b.w). Group IV: Rats were given Fx alone (50 mg/kg b.w) orally and the treatment is for 15 weeks. Results showed the decrease in body weight, serum albumin, antioxidant enzymes, and increased all the liver enzymes, serum bilirubin, and stress markers in DEN induced rats, where as the simultaneous supplementation of Fx reverted them to normal levels. Administration of only Fx did not show any change. Therefore, Fx may serve as a chemotherapeutic agent against liver cancer.

Attenuation of diethylnitrosamine (DEN) - Induced hepatic cancer in experimental model of Wistar rats by Carissa carandas embedded silver nanoparticles.

OBJECTIVE: Hepatic cancer is well known, and leading cancer around the world and remain asymptomatic diseases. Carissa carandas possess anti-proliferative, antioxidant, hepatoprotective property and used in hepatic cancer. The current study deals to evaluate the chemoprotective and therapeutic property of Carissa carandas embedded silver nanoparticles (CCAgNPs) against diethylnitrosamine (DEN) -induced hepatic cancer. MATERIAL AND METHOD: Wistar rats were divided into six groups and hepatic cancer was induced with diethylnitrosamine at the dose of 200 mg/kg BW. The animals were gastrogavaged with standard drug and CCAgNPs for 16 weeks. Serum biomarkers, haematological profile, antioxidants enzymes, inflammatory markers and membrane bound enzymes were assessed to find the anti-proliferative potential of silver nanoparticles. Histological evaluation and microscopic characterizations were also performed to authenticate the outcomes of the present work. RESULTS: Biosynthesized CCAgNPs significantly down-regulated the serum marker enzymes of hepatic and non-hepatic parameter, elevated the levels of enzymatic and non-enzymatic antioxidant profile, elevation in membrane bound enzymes and diminish the levels of inflammatory markers (IL-6, TNF-α, and IL-1ß) via NF-κB pathway. Histopathological features also showed recovery of a hepatic architecture in cancer-induced rats in a dose-dependent manner. CONCLUSION: Our consequences established that such plant mediated silver nanoparticles shown a defensive impact against DEN-induced hepatocarcinogenesis, and serves as a better option to ameliorate the clinical results against hepatocellular carcinoma.

Exome Sequencing of Fresh-frozen or Formalin-fixed Paraffin-embedded B6C3F1/N Mouse Hepatocellular Carcinomas Arising Either Spontaneously or due to Chronic Chemical Exposure.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide; however, the mutational properties of HCC-associated carcinogens remain largely uncharacterized. We hypothesized that mechanisms underlying chemical-induced HCC can be characterized by evaluating the mutational spectra of these tumors. To test this hypothesis, we performed exome sequencing of B6C3F1/N HCCs that arose either spontaneously in vehicle controls ( n = 3) or due to chronic exposure to gingko biloba extract (GBE; n = 4) or methyleugenol (MEG; n = 3). Most archived tumor samples are available as formalin-fixed paraffin-embedded (FFPE) blocks, rather than fresh-frozen (FF) samples; hence, exome sequencing from paired FF and FFPE samples was compared. FF and FFPE samples showed 63% to 70% mutation concordance. Multiple known (e.g., Ctnnb1T41A, BrafV637E) and novel (e.g., Erbb4C559S, Card10A700V, and Klf11P358L) mutations in cancer-related genes were identified. The overall mutational burden was greater for MEG than for GBE or spontaneous HCC samples. To characterize the mutagenic mechanisms, we analyzed the mutational spectra in the HCCs according to their trinucleotide motifs. The MEG tumors clustered closest to Catalogue of Somatic Mutations in Cancer signatures 4 and 24, which are, respectively, associated with benzo(a)pyrene- and aflatoxin-induced HCCs in humans. These results establish a novel approach for classifying liver carcinogens and understanding the mechanisms of hepatocellular carcinogenesis.

Rheum palmatum root extract inhibits hepatocellular carcinoma in rats treated with diethylnitrosamine.

OBJECTIVES: The aim of this study was to investigate the potential anticancer properties of a methanol extract of Rheum palmatum roots against diethylnitrosamine (DENA)-induced hepatocellular carcinoma (HCC) in rats and to characterize its phytoconstituents. METHODS: HPLC-PDA-MS/MS was used to profile the secondary metabolites in R. palmatum root extract. HCC was induced using diethylnitrosamine (DENA). The activity of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT), alpha-fetoprotein (AFP), total proteins, serum albumin and serum globulin was determined. DNA fragmentation and histopathological examination and GST-P immunostaining were also studied. KEY FINDINGS: LC-MS/MS analysis identified 16 compounds belonging to anthraquinones, flavonoids and tannins. The root extract significantly reduced the elevated liver enzymes ALT and AST and increased total proteins, albumin and globulin in HCC-rats. Also, the tumour markers AFP and GGT levels were significantly reduced in HCC-rats treated with the extract. In addition, the extract significantly reduced elevated DNA fragmentation and decreased the numbers and areas of GST-P positive putative foci in HCC-rats. CONCLUSIONS: Rheum palmatum is a potential candidate to be explored for the treatment of hepatocellular carcinoma.

Contradictory effects of mitochondria- and non-mitochondria-targeted antioxidants on hepatocarcinogenesis by altering DNA repair in mice.

Conflicting effects of antioxidant supplementation on cancer prevention or promotion is of great concern to healthy people and cancer patients. Despite recent studies about antioxidants accelerating the progression of lung cancer and melanoma, antioxidants may still play a role in cancer prevention. Both tumor and antioxidants types influence the actual efficacy. However, little is known about the impact of different types of antioxidants on primary hepatocellular carcinoma (HCC), including non-mitochondrial- and mitochondrial-targeted antioxidants. Utilizing mouse models of chemical hepatocarcinogenesis, we showed that administration of non-mitochondria-targeted antioxidants N-acetylcysteine (NAC) and the soluble vitamin E analog, Trolox, prevented tumorigenesis, whereas administration of mitochondria-targeted antioxidants SS-31 (the mitochondria-targeted peptide) and Mito-Q (a derivative of ubiquinone) facilitated tumorigenesis. RNA sequencing revealed that NAC and SS-31 caused very different changes in the oxidation-reduction state and DNA damage response. In diethylnitrosamine (DEN)-treated primary hepatocytes, NAC and Trolox alleviated DNA damage by activating ataxia-telangiectasia mutated (ATM)/ATM and Rad3-related (ATR) for DNA repair whereas SS-31 and Mito-Q aggravated damage by inactivating them. Interestingly, partial recovery of SS-31-scavengened mitochondrial reactive oxygen species (mtROS) could alleviate SS-31-aggravated DNA damage. Localization of ATM between mitochondria and nuclei was altered after NAC and SS-31 treatment. Furthermore, blockage of phospho-ATR (p-ATR) led to the recurrence of NAC-ameliorated DEN HCC. In contrast, reactivation of p-ATR blocked SS-31-promoted DEN HCC. Conclusion: These results demonstrate that the type of antioxidants plays a previously unappreciated role in hepatocarcinogenesis, and provide a mechanistic rationale for exploring the therapeutic use of antioxidants for liver cancer. (Hepatology 2018;67:623-635).

From the Cover: Genomic Effects of Androstenedione and Sex-Specific Liver Cancer Susceptibility in Mice.

Current strategies for predicting carcinogenic mode of action for nongenotoxic chemicals are based on identification of early key events in toxicity pathways. The goal of this study was to evaluate short-term key event indicators resulting from exposure to androstenedione (A4), an androgen receptor agonist and known liver carcinogen in mice. Liver cancer is more prevalent in men compared with women, but androgen-related pathways underlying this sex difference have not been clearly identified. Short-term hepatic effects of A4 were compared with reference agonists of the estrogen receptor (ethinyl estradiol, EE) and glucocorticoid receptor (prednisone, PRED). Male B6C3F1 mice were exposed for 7 or 28 days to A4, EE, or PRED. EE increased and PRED suppressed hepatocyte proliferation, while A4 had no detectable effects. In a microarray analysis, EE and PRED altered >3000 and >670 genes, respectively, in a dose-dependent manner, whereas A4 did not significantly alter any genes. Gene expression was subsequently examined in archival liver samples from male and female B6C3F1 mice exposed to A4 for 90 days. A4 altered more genes in females than males and did not alter expression of genes linked to activation of the mitogenic xenobiotic receptors AhR, CAR, and PPARα in either sex. A gene expression biomarker was used to show that in female mice, the high dose of A4 activated the growth hormone-regulated transcription factor STAT5b, which controls sexually dimorphic gene expression in the liver. These findings suggest that A4 induces subtle age-related effects on STAT5b signaling that may contribute to the higher risk of liver cancer in males compared with females.

Reduction of liver tumerogenic effect of N-nitrosodiethylamine by treatment with ɣ-oryzanol in Balb/C mice.

In recent years, naturally occurring phytochemicals with antioxidant capacity have generated surmount interest in their therapeutic usage against a wide range of pathological and toxicological conditions. The present study was designed to evaluate potential of ɣ-oryzanol (OZ), a bio-active natural antioxidant against hepatocellular carcinoma effect of the carcinogen N-nitrosodiethylamine in Balb/c mice. OZ inhibited the proliferation of Hep-3B cell line in concentration dependent manner. Administration of OZ to N-nitrosodiethylamine induced Balb/c mice for 16 and 32 weeks showed reduction in levels of liver injury markers, restored the levels of liver tumor markers, suppressed the hepatic nodular incidence and multiplicity, and favorably modulated the liver antioxidant status in a time dependent manner. Histologically, no obvious signs of neoplasia in the liver tissues were observed in OZ supplemented rats with N-nitrosodiethylamine induced liver tumerogenesis. OZ was found to be effective for reduction of N-nitrosodiethylamine induced hepatocellular carcinoma.

Commiphora molmol resin attenuates diethylnitrosamine/phenobarbital-induced hepatocarcinogenesis by modulating oxidative stress, inflammation, angiogenesis and Nrf2/ARE/HO-1 signaling.

The objective of the current study was to investigate the possible chemopreventive activity of Commiphora molmol resin (myrrh) extract using a rat model of diethylnitrosamine (DEN)/phenobarbital (PB)-induced early stage hepatocarcinogenesis. Here, we pointed to the modulatory effect of myrrh on oxidative stress, angiogenesis, inflammation and nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Hepatocarcinogenesis was induced in Wistar rats using DEN for initiation and PB as a promoting agent. The rats received 125 or 250 mg/kg C. molmol resin extract throughout the experiment. Both doses of myrrh improved liver function marker enzymes and prevented oval cells proliferation and the distortion of hepatic architecture. The pro-inflammatory cytokine interleukin-6, tumor markers, angiogenesis markers, lipid peroxidation and nitric oxide (NO) were significantly increased in DEN/PB-induced rats. In addition, the antioxidant defenses showed marked reduction in the liver of DEN/PB-induced rats. Oral administration of C. molmol extract to DEN/PB-induced rats significantly decreased circulating markers of inflammation, tumor proliferation and angiogenesis, and liver lipid peroxidation and NO. In addition, C. molmol markedly ameliorated the antioxidant defenses and up-regulated Nrf2 and hemeoxygenase (HO)-1 in the liver of DEN/PB-induced rats. In conclusion, these results provide evidence that C. molmol resin has a potent chemopreventive activity, possibly by up-regulating the Nrf2/HO-1 signaling and attenuation of inflammation, angiogenesis and oxidative stress.

The chemo-prophylactic efficacy of an ethanol Moringa oleifera leaf extract against hepatocellular carcinoma in rats.

CONTEXT: Hepatocellular carcinoma (HCC) is among the most well-known threatening tumours around the world, and the outlook remains bleak. Moringa oleifera Lam. (Moringaceae) exhibits antitumor, antioxidant and hepatoprotective properties. OBJECTIVES: To assess the chemo-prophylactic proficiency and other likely activities of Moringa oleifera leaf ethanol extract (MOLEE) against diethyl nitrosamine (DEN)-induced HCC. MATERIALS AND METHODS: Wistar rats were gastrogavaged with MOLEE (500 mg/kg) for one week and then gastrogavaged with MOLEE and DEN (10 mg/kg) for the following 16 weeks. The progressions of the histological components, serum biomarkers and oxidation of DNA of the liver tissues were resolved to assess the prophylactic impacts. The lipid oxidative biomarker, the cancer prevention agent status and apoptotic proteins were surveyed to assess the potential mechanisms. RESULTS: The MOLEE LD50 was estimated to be 5585 mg/kg. MOLEE (500 mg/kg) administration fundamentally repressed the expansion event of knobs and the normal knob number per knob-bearing livers prompted by DEN, enhanced hepatocellular appearance and altogether significantly decreased (p < 0.05) DEN-induced elevations in serum biochemical records and hepatic 8-hydroxy-2-deoxyguanosine (8-OHdG) levels by 29%. The robotic studies found that MOLEE disrupted the DEN-activated oxidative reactivity damage in rats by 46.8%. Curiously, the expression of Bcl-2, Bcl-xl and ß-arrestin-2 were fundamentally diminished (p < 0.05); however, the expression of Bax and caspase-3 were essentially (p < 0.05) upregulated. DISCUSSION AND CONCLUSIONS: The outcomes presume that MOLEE inspired critical defensive impacts against DEN-induced hepatocarcinogenesis that might be identified with the implementation of antioxidant activity and actuation of apoptosis.