Feasibility of NDEA formation control from DEDTC in chlorination/chloramination by pre-ozonation: Mechanisms and influencing factors

N-nitrosodiethylamine (NDEA), which is the most toxic nitrosamine among the 9 detected species, has been widely detected in drinking water. Amines containing diethylamine (DEA) groups in the structure would generate NDEA during the disinfection processes. The aim of this study was to evaluate the feasibility of reducing NDEA formation from a commonly used dithiocarbamate pesticide sodium diethyldithiocarbamate (DEDTC) in subsequent chlorination and chloramination by pre-ozonation. The results demonstrated that NDEA could be generated directly during ozonation, its amounts increased from 0 to 14.34 μg/L with increasing ozone dosages (0-4 mg/L), which was higher than that chlorination (2.68 μg/L) and chloramination (4.91 μg/L) when the initial concentration of DEDTC was 20 μM. Pre-ozonation significantly raised NDEA formation from 2.68 to15.32 μg/L in subsequent chlorination; and that from 4.91 to 9.54 μg/L during subsequent chloramination processes. The addition of •OH scavenger tert-butanol (tBA) increased the production of NDEA from 8.14 to 20.80 μg/L during ozonation, and that from 6.76 to17.98 μg/L in O3/HClO process, 8.74 to 17.33 μg/L in O3/NH2Cl process. Except for NO3- and CO32-, most of the co-existing substances promoted NDEA generation from DEDTC under disinfection conditions. Based on the results of Gaussian theory calculations, GC/MS and UPLC-Q-TOFMS analysis, the influencing mechanisms of pre-ozonation on NDEA generation in the subsequent disinfection process were proposed. In addition, not only acute/chronic toxicity calculation but also luminescent bacteria test was performed to assess the possibility of pre-ozonation on the risk control of DEDTC. The research results fill a gap in the control of NDEA pollution and help to develop a safer ozone oxidation technology.

Amelioration effect of 18β-Glycyrrhetinic acid on methylation inhibitors in hepatocarcinogenesis -induced by diethylnitrosamine

Aim

suppression of methylation inhibitors (epigenetic genes) in hepatocarcinogenesis induced by diethylnitrosamine using glycyrrhetinic acid.

Method

In the current work, we investigated the effect of sole GA combined with different agents such as doxorubicin (DOX) or probiotic bacteria (Lactobacillus rhamanosus) against hepatocarcinogenesis induced by diethylnitrosamine to improve efficiency. The genomic DNA was isolated from rats' liver tissues to evaluate either methylation-sensitive or methylation-dependent resection enzymes. The methylation activity of the targeting genes DLC-1, TET-1, NF-kB, and STAT-3 was examined using specific primers and cleaved DNA products. Furthermore, flow cytometry was used to determine the protein expression profiles of DLC-1 and TET-1 in treated rats' liver tissue.

Results

Our results demonstrated the activity of GA to reduce the methylation activity in TET-1 and DLC-1 by 33.6% and 78%, respectively. As compared with the positive control. Furthermore, the association of GA with DOX avoided the methylation activity by 88% and 91% for TET-1 and DLC-1, respectively, as compared with the positive control. Similarly, the combined use of GA with probiotics suppressed the methylation activity in the TET-1 and DLC-1 genes by 75% and 81% for TET-1 and DLC-1, respectively. Also, GA and its combination with bacteria attenuated the adverse effect in hepatocarcinogenesis rats by altering potential methylomic genes such as NF-kb and STAT3 genes by 76% and 83%, respectively.

Conclusion

GA has an ameliorative effect against methylation inhibitors in hepatocellular carcinoma (HCC) by decreasing the methylation activity genes.

Targeting the SphK1/S1P/PFKFB3 axis suppresses hepatocellular carcinoma progression by disrupting glycolytic energy supply that drives tumor angiogenesis

BACKGROUND

Hepatocellular carcinoma (HCC) remains a leading life-threatening health challenge worldwide, with pressing needs for novel therapeutic strategies. Sphingosine kinase 1 (SphK1), a well-established pro-cancer enzyme, is aberrantly overexpressed in a multitude of malignancies, including HCC. Our previous research has shown that genetic ablation of Sphk1 mitigates HCC progression in mice. Therefore, the development of PF-543, a highly selective SphK1 inhibitor, opens a new avenue for HCC treatment. However, the anti-cancer efficacy of PF-543 has not yet been investigated in primary cancer models in vivo, thereby limiting its further translation.

METHODS

Building upon the identification of the active form of SphK1 as a viable therapeutic target in human HCC specimens, we assessed the capacity of PF-543 in suppressing tumor progression using a diethylnitrosamine-induced mouse model of primary HCC. We further delineated its underlying mechanisms in both HCC and endothelial cells. Key findings were validated in Sphk1 knockout mice and lentiviral-mediated SphK1 knockdown cells.

RESULTS

SphK1 activity was found to be elevated in human HCC tissues. Administration of PF-543 effectively abrogated hepatic SphK1 activity and significantly suppressed HCC progression in diethylnitrosamine-treated mice. The primary mechanism of action was through the inhibition of tumor neovascularization, as PF-543 disrupted endothelial cell angiogenesis even in a pro-angiogenic milieu. Mechanistically, PF-543 induced proteasomal degradation of the critical glycolytic enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3, thus restricting the energy supply essential for tumor angiogenesis. These effects of PF-543 could be reversed upon S1P supplementation in an S1P receptor-dependent manner.

CONCLUSIONS

This study provides the first in vivo evidence supporting the potential of PF-543 as an effective anti-HCC agent. It also uncovers previously undescribed links between the pro-cancer, pro-angiogenic and pro-glycolytic roles of the SphK1/S1P/S1P receptor axis. Importantly, unlike conventional anti-HCC drugs that target individual pro-angiogenic drivers, PF-543 impairs the PFKFB3-dictated glycolytic energy engine that fuels tumor angiogenesis, representing a novel and potentially safer therapeutic strategy for HCC.

Sericin and melatonin mitigate diethylnitrosamine-instigated testicular impairment in mice: Implications of oxidative stress, spermatogenesis, steroidogenesis, and modulation of Nrf2/WT1/SF-1 signaling pathways

AIMS

This study aimed to investigate the therapeutic influence of combination therapy with sericin and melatonin on attenuating diethylnitrosamine (DEN)-instigated testicular dysfunction in mice and defining the molecular mechanisms involved in orchestrating redox signaling pathways and restoring spermatogenesis and steroidogenesis.

MATERIALS AND METHODS

Different groups of male Swiss albino mice were established and injected with respective drugs intraperitoneally. Semen analysis, hormonal assays, and oxidative stress biomarkers were evaluated. Additionally, melatonin and its receptors, WT1, SF-1, vimentin, Nrf2, and ANXA1 expressions were assessed. Histopathological and ultrastructural features of the testes were investigated by semithin, SEM, and TEM analyses.

KEY FINDINGS

Exposure to DEN exhibited pathophysiological consequences, including a remarkable increase in lipid peroxidation associated with substantial diminutions in SOD, CAT, GPx, GSH, GSH:GSSG, and GST. Furthermore, it disrupted spermatozoa integrity, testosterone, FSH, LH, melatonin, and its receptors (MT1 and MT2) levels, implying spermatogenesis dysfunction. By contrast, treatment with sericin and melatonin significantly restored these disturbances. Interestingly, the combination therapy of sericin and melatonin noticeably augmented the Nrf2, WT1, and SF-1 expressions compared to DEN-treated mice, deciphering the amelioration perceived in antioxidant defense and spermatogenesis inside cells. Furthermore, immunohistochemical detection of ANXA1 alongside histopathological and ultrastructural analyses revealed evident maintenance of testicular structures without discernible inflammation or anomalies in mice administered with sericin and melatonin compared to the DEN-treated group.

SIGNIFICANCE

Our findings highlighted that treatment with sericin and melatonin alleviated the testicular tissues in mice from oxidative stress and dysregulated spermatogenesis and steroidogenesis engendered by DEN.

The essential role of O-GlcNAcylation in hepatic differentiation

BACKGROUND

O-GlcNAcylation is a post-translational modification catalyzed by the enzyme O-GlcNAc transferase, which transfers a single N-acetylglucosamine sugar from UDP-GlcNAc to the protein on serine and threonine residues on proteins. Another enzyme, O-GlcNAcase (OGA), removes this modification. O-GlcNAcylation plays an important role in pathophysiology. Here, we report that O-GlcNAcylation is essential for hepatocyte differentiation, and chronic loss results in fibrosis and HCC.

METHODS

Single-cell RNA-sequencing (RNA-seq) was used to investigate hepatocyte differentiation in hepatocyte-specific O-GlcNAc transferase-knockout (OGT-KO) mice with decreased hepatic O-GlcNAcylation and in O-GlcNAcase-KO mice with increased O-GlcNAcylation in hepatocytes. Patients HCC samples and the diethylnitrosamine-induced HCC model were used to investigate the effect of modulation of O-GlcNAcylation on the development of liver cancer.

RESULTS

Loss of hepatic O-GlcNAcylation resulted in disruption of liver zonation. Periportal hepatocytes were the most affected by loss of differentiation, characterized by dysregulation of glycogen storage and glucose production. O-GlcNAc transferase-KO mice exacerbated diethylnitrosamine-induced HCC development with increased inflammation, fibrosis, and YAP signaling. Consistently, O-GlcNAcase -KO mice with increased hepatic O-GlcNAcylation inhibited diethylnitrosamine-induced HCC. A progressive loss of O-GlcNAcylation was observed in patients with HCC.

CONCLUSIONS

Our study shows that O-GlcNAcylation is a critical regulator of hepatic differentiation, and loss of O-GlcNAcylation promotes hepatocarcinogenesis. These data highlight increasing O-GlcNAcylation as a potential therapy in chronic liver diseases, including HCC.

Lactosylated Chitosan Nanoparticles Potentiate the Anticancer Effects of Telmisartan In Vitro and in a N-Nitrosodiethylamine-Induced Mice Model of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related mortality worldwide. Telmisartan (TLM), a BSC class II drug, has been reported to have antiproliferative activity in HCC. However, its therapeutic activity is limited by poor bioavailability and unpredictable distribution. This work aimed to enhance TLM's liver uptake for HCC management through passive and active targeting pathways utilizing chitosan nanoparticles decorated with lactose (LCH NPs) as a delivery system. In vitro cell cytotoxicity and cellular uptake studies indicated that TLM-LCH NPs significantly (p < 0.05) enhanced the antiproliferative activity and cellular uptake percentage of TLM. In vivo bioavailability and liver biodistribution studies indicated that TLM-LCH NPs significantly (p < 0.05) enhanced TLM concentrations in plasma and the liver. The relative liver uptake of TLM from TLM-LCH NPs was 2-fold higher than that of unmodified NPs and 5-fold higher than that of plain TLM suspension. In vivo studies of a N-nitrosodiethylamine-induced HCC model revealed that administration of TLM through LCH NPs improved liver histology and resulted in lower serum alpha-fetoprotein (AFP), matrix metalloproteinase 2 (MMP-2), vascular endothelial growth factor (VEGF) levels, and liver weight index compared to plain TLM and TLM-loaded unmodified NPs. These results reflected the high potentiality of LCH NPs as a liver-targeted delivery system for TLM in the treatment of HCC.

paniala seeds attenuated the early stage of diethylnitrosamine and 1,2-dimethylhydrazine-induced colorectal carcinogenesis

BACKGROUND

Dichloromethane extract of Cleistocalyx nervosum var. paniala seeds exhibited an anticarcinogenicity against chemically-induced the early stages of carcinogenesis in rats. This study aimed to identify anticarcinogenic compounds from C. nervosum seed extract (CSE).

METHODS

Salmonella mutation assay was performed to determine mutagenicity and antimutagenicity of partially purified and purified compounds of CSE. The anticarcinogenic enzyme-inducing activity was measured in Hepa1c1c7. Moreover, the anticancer potency was examined on various human cancer cell lines. The anticarcinogenicity of DMC was investigated using dual-organ carcinogenicity model. The number of preneoplastic lesions was evaluated in the liver and colon. The inhibitory mechanisms of DMC on liver- and colorectal carcinogenesis were investigated.

RESULTS

Six partially purified fractions (MK1 - MK6) and purified compounds, including 2,4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC) and hariganetin, were obtained from CSE. Among these fractions, MK4 and DMC presented the greatest antimutagenicity against indirect mutagens in bacterial model. Moreover, MK5 possessed an effective anticarcinogenic enzyme inducer in Hepa1c1c7. The MK4, DMC and CSE showed greater anticancer activity on all cell lines and exhibited the most effective toxicity on colon cancer cells. Furthermore, DMC inhibited the formation of colonic preneoplastic lesions in carcinogens-treated rats. It reduced PCNA-positive cells and frequency of BCAC in rat colon. DMC also enhanced the detoxifying enzyme, GST, in rat livers.

CONCLUSIONS

DMC obtained from CSE may be a promising cancer chemopreventive compound of colorectal cancer process in rats. It could increase detoxifying enzymes and suppress the cell proliferation process resulting in prevention of post-initiation stage of colorectal carcinogenesis.

Metformin Prevents NDEA-Induced Memory Impairments Associated with Attenuating Beta-Amyloid, Tumor Necrosis Factor-Alpha, and Interleukin-6 Levels in the Hippocampus of Rats

N-nitrosodiethylamine (NDEA) is a potential carcinogen known to cause liver tumors and chronic inflammation, diabetes, cognitive problems, and signs like Alzheimer's disease (AD) in animals. This compound is classified as probably carcinogenic to humans. Usual sources of exposure include food, beer, tobacco, personal care products, water, and medications. AD is characterized by cognitive decline, amyloid-β (Aβ) deposit, tau hyperphosphorylation, and cell loss. This is accompanied by neuroinflammation, which involves release of microglial cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin 1β (IL-1β), by nuclear factor kappa B (NF-κB) upregulation; each are linked to AD progression. Weak PI3K/Akt insulin-signaling inhibits IRS-1 phosphorylation, activates GSK3β and promotes tau hyperphosphorylation. Metformin, an antihyperglycemic agent, has potent anti-inflammatory efficacy. It reduces proinflammatory cytokines such as IL-6, IL-1β, and TNF-α via NF-κB inhibition. Metformin also reduces reactive oxidative species (ROS) and modulates cognitive disorders reported due to brain insulin resistance links. Our study examined how NDEA affects spatial memory in Wistar rats. We found that all NDEA doses tested impaired memory. The 80 µg/kg dose of NDEA increased levels of Aβ1-42, TNF-α, and IL-6 in the hippocampus, which correlated with memory loss. Nonetheless, treatment with 100 mg/kg of metformin attenuated the levels of pro-inflammatory cytokines and Aβ1-42, and enhanced memory. It suggests that metformin may protect against NDEA-triggered memory issues and brain inflammation.

[Health risk assessment associated with priority potentially hazardous chemical compounds detected in canned meat and meat-and-vegetable food for infants]

Assessment of public health safety associated with chemical contaminants consumed with food is an important component for solving the tasks of ensuring the sanitary and epidemiological well-being of the population. For these purposes, it is necessary to establish priority potentially dangerous compounds among the identified undeclared and unintended chemical contaminants for further consumers risk assessment. In conditions of unacceptable levels of health risk, it is necessary to decide whether it is advisable to develop new or change existing hygiene standards for these substances. The aim of the study was to assess the health risk associated with priority potentially dangerous unintended chemical components of contamination in canned meat and meat-and-vegetable products for infants (using the example of N-nitrosoamines). Material and methods. The selection of priority chemical compounds and public health risk assessment were carried out in accordance with the procedure for identifying undeclared and potentially dangerous unintended chemicals in food and using modified approaches based on the results of previous studies. Health risk assessment for infants consuming canned meat and meat-and-vegetables containing priority chemicals was carried out in accordance with the methodology approved by the Eurasian Economic Commitee, as well as using the Guidelines for assessing risks to public health when exposed to environmental pollutants. To characterize the calculated risk levels, the classification proposed in the draft document «Guidelines for assessing risks to public health when exposed to environmental pollutants» was used. Results. N-nitrosoamines are classified as chemical contaminants that are a priority for public health risk assessment, identified on the basis of the potential hazard category. A comparative health risk assessment for the target group consumers of canned meat and meat-and-vegetables sold on the territory of the Russian Federation and the Socialistic Republic of Vietnam showed the presence of an unacceptable risk to the health of the Russian population in relation to non-carcinogenic adverse health effects associated with the intake of N-nitrosodimethylamine (NDMA) (hazard quotient HQ=1.1) and N-nitrosodibuthylamine (HQ=5.25). Many experimental (animal) researches confirm the formation of negative effects and potential harm to humans, formed by the consumption of N-nitrosoamines with food. At the same time, the level of the exposure of N-nitrosoamines during oral administration was assessed mainly from the side of carcinogenic effects, however, this study reflects the hazard, including from non-carcinogenic risks associated not only with NDMA and N-nitrosodiethylamine, for which there is a hygienic standard, but also for other N-nitrosoamines, for which there is no hygienic regulation. In turn, the European Food Safety Agency's (EFSA) study notes that it is necessary to conduct a risk assessment for human health in relation to other N-nitrosoamines identified in food, and, if necessary, rationing of these compounds, which is also confirmed by this study. Conclusion. The conducted health risk assessment of the target population of Russia (infants from 6 months to 3 years) consuming the studied types of products containing N-nitrosoamines showed the presence of unacceptable levels of non-carcinogenic health risks in relation to the development processes and impaired liver function. In connection with the identified risks to the health of the target population, it is advisable to establish maximum permissible levels not only for the amount of NDMA and N-nitrosodiethylamine, but also for other N-nitrozoamines identified by the results of the study, with their subsequent regulation.

A survey of industrial N-nitrosamine discharges in Switzerland

N-nitrosamines are formed during different industrial processes and are of significant concern due to their carcinogenic and mutagenic properties. This study reports concentrations of N-nitrosamines in eight different industrial wastewater treatment plants in Switzerland and the variability of their abundance. Only four N-nitrosamines species, N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosodibutylamine (NDPA) and N-nitrosomorpholine (NMOR) were above the limit of quantification in this campaign. Remarkably high concentrations (i.e. up to 975 μg NDMA/L, 90.7 μg NDEA/L, 1.6 μg NDPA/L and 710 μg NMOR/L) of these N-nitrosamines were detected at seven of eight sites. These concentrations are two to five orders of magnitude higher than those typically detected in municipal wastewater effluents. These results suggest that industrial effluents may be a major source of N-nitrosamines. Although very high concentrations of N-nitrosamine have been detected in industrial discharges, various processes in surface water can partially mitigate their concentrations (e.g. photolysis, biodegradation and volatilization) and hence the risk to human health and aquatic ecosystems. Nevertheless, there is little information on long-term effects on aquatic organisms and therefore the discharge of N-nitrosamines to the environment should be avoided until the impact on ecosystems is assessed. During winter a less efficient mitigation of N-nitrosamines can be expected (lower biological activity, less sunlight) and therefore, emphasis should be put on this season in future risk assessment studies.

Influencing pathways and toxicity changes of pre-ozonation on carcinogenic NDEA formation from greenhouse gas adsorbent DEAPA in subsequent disinfection processes

This study was to evaluate the feasibility of controlling carcinogenic nitrosodiethylamine (NDEA) formation from greenhouse gas adsorbent 3-diethylaminopropylamine (DEAPA) by pre-O₃ in subsequent chlorination/chloramination processes. The result indicated that the NDEA yields (0.4 %) during chlorination was 1.3 times of that during chloramination (0.3 %); pre-oxidation with 4 mg/L O₃ significantly cut down its formation; the reduction rates were up to 67.5 and 48.5 %, respectively. OH scavenger greatly augmented the final NDEA amount from 1.86 to 5.05 μg/L during ozonation, while its roles on subsequent processes differed with disinfection methods as well as O₃(g) dosages. Most of co-existed substances inhibited NDEA generation, except NO₂^-, CO₃^2- and SO₄^2-, which slightly promoted during ozonation. Basing on Gaussian calculation, GC/MS and UPLC-Q-TOF-MS analysis, the influencing mechanisms of pre-O₃ on NDEA formation in subsequent disinfection processes were proposed. In addition, the calculated toxicity analysis as well as the whole toxicity was applied to evaluate the possibility of pre-O₃ on risk control.

Antitumor Activity of Chitosan-Coated Iron Oxide Nanocomposite Against Hepatocellular Carcinoma in Animal Models

Hepatocellular carcinoma (HCC) is among the most prevalent and lethal cancers worldwide. Chitosan-coated iron oxide nanocomposite (Fe₃O₄/Cs) is a promising bio-nanomaterial for many biological applications. The objective of this research was to evaluate the anticancer efficacy of Fe₃O₄/Cs against HCC in animal models. Fe₃O₄ nanoparticles were prepared and added to chitosan solution; then, the mixture was exposed to gamma radiation at a dose of 20 kGy. Rats have received diethylnitrosamine (DEN) orally at a dose of 20 mg/kg body weight 5 times per week during a period of 10 weeks to induce HCC and then have received Fe₃O₄/Cs intraperitoneal injection at a dose of 50 mg/kg body weight 3 times per week during a period of 4 weeks. After the last dose of Fe₃O₄/Cs administration, animals were sacrificed. DEN induced upregulation of PI3K/Akt/mTOR and MAPK (ERK, JNK, P38) signaling pathways and inflammatory markers (TLR4, iNOS, and TNF-α). DEN also decreases cleaved caspase-3 and increases liver enzymes (ALT, AST, and GGT) activities. Administration of Fe₃O₄/Cs significantly ameliorated the above-mentioned parameters.

Boron attenuated diethylnitrosamine induced hepatocellular carcinoma in C3H/HeN mice via alteration of oxidative stress and apoptotic pathway

BACKGROUND

Reactive oxygen species (ROS) regulate various cellular signaling pathways and play an important role in the occurrence and development of hepatocellular carcinoma (HCC). Excessive accumulation of ROS can promote HCC. Trace element boron has a wide range of biological effects, including anti-oxidation, anti-tumor, immune regulation and so on.

METHODS

In this study, we investigated the anticancer effects of Sodium tetraborate decahydrate (NaB) in improving oxidative stress and regulating apoptosis in mouse HCC. HCC was induced by intraperitoneal injection of diethylnitrosamine (DEN) 25 mg/kg once at the age of 2 weeks and 100 mg/kg again at the age of 6 weeks in healthy C3H/HeN male mice. At 8 weeks of age, different concentrations of NaB were given intragastric treatment once a day for 20 weeks. Oxidative stress markers, antioxidant status and liver enzyme analysis were detected to evaluate the effectiveness of NaB in inhibiting cancer induction. The anticancer properties of NaB were confirmed by observing the liver index and morphology, and analyzing the expression of apoptotic genes and proteins. Our results showed that boron significantly reduced the production of ROS, and down-regulated the expression of the anti-apoptotic protein Bcl2 and up-regulated the expression of the pro-apoptotic proteins P53, Bax, and caspase 3.

CONCLUSION

Boron has great potential to reduce the effects of oxidative stress, which may help it inhibit the progression of HCC.

Intestinal microecology in mice bearing diethylnitrosamine-induced primary hepatocellular carcinoma

OBJECTIVE

To explore the characteristics of intestinal microecology in hepatocellular carcinoma (HCC) model mice.

METHODS

C57BL/6 male mice aged 2 weeks were divided into normal control group and HCC model group. Mice in HCC model group were exposed to a single intraperitoneal injection of diethylnitrosamine (DEN) 2 weeks after birth; the surviving mice were intraperitoneally injected with 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP), once every 2 weeks for 8 times starting from the 4 th week after birth. Mice in each group were randomly selected and sacrificed at 10 th, 18 th and 32 nd weeks after birth, respectively, the liver tissue samples were obtained for histopathological examination. At the 32 nd week, all mice in both groups were sacrificed and the feces samples were collected under sterile conditions right before the sacrifice. The feces samples were sequenced for the V3-V4 hypervariable regions of the 16S rRNA gene, and the species abundance, flora diversity and phenotype, as well as flora correlation and functional prediction were analyzed.

RESULTS

Alpha diversity analysis showed that all Good's coverage reached the maximum value of 1.00, and the differences in the Observed features, Chao1 index, Shannon index and Simpson index of the intestinal flora of mice between normal control group and HCC model group were all statistically significant (all P<0.05). Beta diversity analysis showed that PCoA based on weighted or unweighted Unifrac distances all yielded R>0, confirming that the intra-group differences of the samples were less than the inter-group differences; the trend of separation between the two groups was significant ( P<0.05). Bacteroidetes, Firmicutes, Actinobacteria and Patescibacteria were the dominant taxa at the phylum level in both normal control group and HCC model group. However, compared with normal control group, the abundance of Bacteroidetes in HCC model group was significantly decreased ( P<0.01), while the abundance of Patescibacteria was significantly increased ( P<0.05). Moreover, the dominant taxa at the genus level in normal control group mainly included Muribaculaceae_unclassified, Paramuribaculum, Muribaculum, Lachnospiraceae_NK4A 136 group, Olsenella. The dominant taxa at the genus level in HCC model group mainly included Akkermansia, Dubosiella, Muribaculaceae_unclassified, Lachnospiraceae_NK4A 136 group, Coriobacteriaceae_UCG-002. There were 30 genera with statistically significant differences in relative abundance at the genus level between the two groups (all P<0.05). LEfSe analysis of the intestinal flora of mice in the two groups revealed a total of 14 multi-level differential taxa (all P<0.05, LDA score>4.0), which were mainly enriched in Bacteroidetes. The enrichment of 10 differential taxa including Bacteroidetes, Bacteroidia, Bacteroidales, Muribaculaceae, etc. were found in normal control group, and the enrichment of 4 differential taxa including Dubosiella, Peptostreptococus, etc. were found in HCC model group. There were both positive and negative correlations between the dominant intestinal genera in normal control group (|rho|>0.5, P<0.05), while the correlations of the dominant intestinal genera in HCC model group, being less complex than that in normal control group, were all positive. The relative abundance of gram positive and mobile element containing in the intestinal flora of mice in HCC model group was significantly up-regulated compared with normal control group (both P<0.05), while that of gram negative ( P<0.05) and pathogenic potential ( P<0.05) was significantly down-regulated. The metabolic pathways of the intestinal flora in the two groups were significantly different. For instance, 18 metabolic pathways were enriched in normal control group (all P<0.005), including those related to energy metabolism, cell division, nucleotide metabolism, etc., while 12 metabolic pathways were enriched in HCC model group (all P<0.005), including those related to energy metabolism, amino acid metabolism, carbohydrate metabolism, etc. Conclusions: The amount of intestinal flora in DEN-induced primary HCC model mice decreased, and the composition, correlation, phenotype and function of the intestinal flora in mice were significantly altered. Bacteroidetes at the phylum level, as well as several microbial taxa at the genus level such as Muribaculaceae_unclassified, Muribaculum, Peptostreptococus and Dubosiella could be closely associated with DEN-induced primary HCC in mice.

Aidi injection altered the activity of CYP2D4, CYP1A2, CYP2C19, CYP3A2, CYP2E1 and CYP2C11 in normal and diethylnitrosamine-induced hepatocellular carcinoma in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Aidi injection (ADI), a traditional chinese medicine preparation, is widely used in combination with chemotherapy for the treatment of various malignant tumors, such as hepatocellular carcinoma (HCC). Studies have shown that changes in cytochrome P450 (CYP450) activity in disease states would affect the metabolism of drugs in vivo, especially liver diseases. However, the changes of Aidi injection on the activities of CYP2D4, CYP1A2, CYP2C19, CYP3A2, CYP2E1 and CYP2C11 in normal and HCC states are still unknown.

AIM OF THE STUDY

The cocktail probe drugs method was used to investigate the effects of ADI on the activity of CYP2D4, CYP1A2, CYP2C19, CYP3A2, CYP2E1 and CYP2C11 in normal and HCC rats.

MATERIALS AND METHODS

The HCC rats was induced by diethylnitrosamine (DEN). Then, both normal and HCC rats were randomly divided into 2 groups (n = 6). They were given saline or ADI (10 mL/kg/d, i.p) for 2 weeks, respectively. On the fifteenth day, cocktail probe mixing solution, including metoprolol (10 mg/kg), caffeine (1.0 mg/kg), omeprazole (2.0 mg/kg), midazolam (2.0 mg/kg), chlorzoxazone (4.0 mg/kg) and tolbutamide (0.5 mg/kg), was injected into tail vein of all rats in each group. The blood sample was obtained at specified time. After the protein is precipitated, six probe drugs are analyzed by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS).

RESULTS

Compared with control group, the activity of CYP3A2 and CYP2E1 was significantly lower in the ADI group. Compared with the model group, the activities of CYP1A2, CYP3A2, CYP2E1, and CYP2C11 enzymes in the ADI model group were significantly reduced. Additionally, the activity of CYP2D4, CYP1A2, CYP2C19, CYP3A2, CYP2E1 and CYP2C11 enzymes in model group was significantly lower than control group.

CONCLUSIONS

ADI can inhibit a lot of CYP450 enzyme, so it may reduce the dosage of chemotherapeutic drugs to reach the required plasma concentration of chemotherapeutic drugs, which is of great significance for the combination of anti-tumor chemotherapeutic drugs and is worthy of further in-depth study and clinical attention.

Loss of Hepatic Transcription Factor EB Attenuates Alcohol-Associated Liver Carcinogenesis

Alcohol is a well-known risk factor for hepatocellular carcinoma. Autophagy plays a dual role in liver cancer, as it suppresses tumor initiation and promotes tumor progression. Transcription factor EB (TFEB) is a master regulator of lysosomal biogenesis and autophagy, which is impaired in alcohol-related liver disease. However, the role of TFEB in alcohol-associated liver carcinogenesis is unknown. Liver-specific Tfeb knockout (KO) mice and their matched wild-type (WT) littermates were injected with the carcinogen diethylnitrosamine (DEN), followed by chronic ethanol feeding. The numbers of both total and larger tumors increased significantly in DEN-treated mice fed ethanol diet than in mice fed control diet. Although the number of tumors was not different between WT and L-Tfeb KO mice fed either control or ethanol diet, the number of larger tumors was less in L-Tfeb KO mice than in WT mice. No differences were observed in liver injury, steatosis, inflammation, ductular reaction, fibrosis, and tumor cell proliferation in DEN-treated mice fed ethanol. However, the levels of glypican 3, a marker of malignant hepatocellular carcinoma, markedly decreased in DEN-treated L-Tfeb KO mice fed ethanol in comparison to the WT mice. These findings indicate that chronic ethanol feeding promotes DEN-initiated liver tumor development, which is attenuated by genetic deletion of hepatic TFEB.

Maresin-1 Prevents Liver Fibrosis by Targeting Nrf2 and NF-κB, Reducing Oxidative Stress and Inflammation

Liver fibrosis is a complex process characterized by the excessive accumulation of extracellular matrix (ECM) and an alteration in liver architecture, as a result of most types of chronic liver diseases such as cirrhosis, hepatocellular carcinoma (HCC) and liver failure. Maresin-1 (MaR1) is derivative of ω-3 docosahexaenoic acid (DHA), which has been shown to have pro-resolutive and anti-inflammatory effects. We tested the hypothesis that the application of MaR1 could prevent the development of fibrosis in an animal model of chronic hepatic damage. Sprague-Dawley rats were induced with liver fibrosis by injections of diethylnitrosamine (DEN) and treated with or without MaR1 for four weeks. In the MaR1-treated animals, levels of AST and ALT were normalized in comparison with DEN alone, the hepatic architecture was improved, and inflammation and necrotic areas were reduced. Cell proliferation, assessed by the mitotic activity index and the expression of Ki-67, was increased in the MaR1-treated group. MaR1 attenuated liver fibrosis and oxidative stress was induced by DEN. Plasma levels of the pro-inflammatory mediators TNF-α and IL-1β were reduced in MaR1-treated animals, whereas the levels of IL-10, an anti-inflammatory cytokine, increased. Interestingly, MaR1 inhibited the translocation of the p65 subunit of NF-κB, while increasing the activation of Nrf2, a key regulator of the antioxidant response. Finally, MaR1 treatment reduced the levels of the pro-fibrotic mediator TGF-β and its receptor, while normalizing the hepatic levels of IGF-1, a proliferative agent. Taken together, these results suggest that MaR1 improves the parameters of DEN-induced liver fibrosis, activating hepatocyte proliferation and decreasing oxidative stress and inflammation. These results open the possibility of MaR1 as a potential therapeutic agent in fibrosis and other liver pathologies.

Ameliorative potential of manganese nanoparticles with low-level ionizing radiation against experimentally induced hepatocarcinogenesis

Nanotechnology is a rich field with infinite possibilities of drug designs for cancer treatment. We aimed to biosynthesize manganese nanoparticles (Mn NPs) using Lactobacillus helveticus to investigate its anticancer synergistic effect with low-dose gamma radiation on HCC-induced rats. Diethylnitrosamine (DEN) (20 mg/kg BW, 5 times a week for 6 weeks) induced HCC in rats. Rats received Mn NPs (5 mg/kg BW/day) by gastric gavage over 4 weeks concomitant with single dose of gamma radiation (γ-R) (0.25 Gy). Characterization, cytotoxicity, and anticancer activity of Mn NPs were evaluated. DEN-induced significant liver dysfunction (alanine transaminase activity ALT, total proteins, and albumin levels) associated with significant increase in lipid peroxidation levels with reduction in super oxide dismutase activity. Furthermore, DEN intoxication is sponsored for remarkable increase in levels of Alfa-fetoprotein, tumor necrosis factor α, vascular endothelial growth factor, and transforming growth factor beta with remarkable decrease in caspase 3 and cytochrome c. Treatment with Mn NPs (4.98-11.58 nm) and single dose gamma radiation evoked significant repair in ALT, total protein, and albumin accompanied with balanced oxidative status, diminished inflammatory biomarkers, angiogenic factor, and growth factor with restoration in apoptotic factors. Mn NPs revealed obvious in vitro cytotoxic activity against HepG2 cell line in a dose-dependent manner. Our findings were well appreciated with the histopathological study. In conclusion, a new approach of the single or combined use of Mn NPs with low-dose γ-radiation regimens as promising paradigm for HCC treatment is recommended.

Mulberry fruit polysaccharides alleviate diethylnitrosamine/phenobarbital-induced hepatocarcinogenesis in vivo: the roles of cell apoptosis and inflammation

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, and chemoprevention represents a feasible treatment to reduce the mortality of this carcinoma. Mulberry fruit polysaccharides (MFP) possess immunoregulatory and anti-inflammatory effects, which have been reported to alleviate liver damage evoked by CCl4 or alcohol in previous reports. However, its chemopreventive effect against liver carcinogenesis is insufficient. The present study was aimed to investigate the possible role of MFP as a pro-apoptosis, and anti-inflammatory agent to possess its chemoprevention property. Hepatocarcinogenesis was induced by diethylnitrosamine/phenobarbital (DEN/PB) for 14 weeks. The DEN/PB-administered rats were co-treated with different doses of MFP (50 or 100 mg/kg body weight) by oral gavage for 14 weeks. Basic hepatic function indexes (AST, ALT, ALP, GGT, total bilirubin, and albumin), and hepatic tumor biomarkers (AFP, CEA, and CA19.9), together with histological assessment were performed. Besides, the hepatic apoptosis markers (Bcl-2, Bax, caspase3, and caspase9), inflammation markers (IL-1β, TNF-α, and NF-κB), and mutT homologue gene 1 (MTH1) were examined. Oral gavage of MFP inhibited the elevations of hepatic function indexes and hepatic tumor biomarkers and alleviated pathological changes in hepatic tissue. In addition, the hepatic apoptosis markers, inflammation markers, and the mRNA level of MTH1 were abnormal in DEN/PB group, which were reversed by MFP treatment. In conclusion, MFP is an effective agent that provides chemoprevention against DEN/PB-evoked hepatocarcinogenesis via inhibition of inflammation and induction of apoptosis.

Degradation of N-Nitrosodiethylamine in aqueous solution by gamma-irradiation

N-Nitrosodiethylamine (NNDEA) is a toxic compound which is affranchised into the medium mostly via industrial wastewater. For the investigation of degradation mechanism of NNDEA, the aqueous solutions of NNDEA were exposed to Advanced Oxidation processes (AOP's) such as gamma-irradiation, ozonation, UV irradiation and UV/Ozone (ozone effect) and UV/H2O2 (hydrogen peroxide effect). Since the structure of NNDEA is small, it is rapidly degraded in all processes except UV-irradiation process but forming acetic acid and formic acid just was seen in gamma and UV/H₂O₂processes. In the other processes, NNDEA is transformed directly to nitrite and nitrate which they can form NNDEA again in the medium. The concentration of NNDEA was decreased from 50 to 21 mg L^-1 after 2.20 kGy gamma-irradiation. After 2.85 kGy gamma irradiation, NNDEA was completely removed from the medium. The results showed that the concentration of NNDEA decreased with UV-irradiation time, the concentration of 50 mg L^-1 NNDEA was 42, 30, 24 and 19 mg L^-1 after 10, 20, 40 and 60 min UV-irradiation, respectively. It has been investigated that the UV-irradiation does not have much effect on the degradation of 50 mg L^-1 NNDEA solution and requires long-term irradiation. In this study, gamma-irradiation was chosen as the best method because of the complete degradation effect and the prevention of the reformation of the NNDEA.

Pharmacokinetic herb-drug interactions between Aidi injection and doxorubicin in rats with diethylnitrosamine-induced hepatocellular carcinoma

BACKGROUND

Aidi Injection (ADI), a Chinese herbal preparation with anti-cancer activity, is used for the treatment of hepatocellular carcinoma (HCC). Several clinical studies have shown that co-administration of ADI with doxorubicin (DOX) is associated with reduced toxicity of chemotherapy, enhanced clinical efficacy and improved quality of life for patients. However, limited information is available about the herb-drug interactions between ADI and DOX. The study aimed to investigate the pharmacokinetic mechanism of herb-drug interactions between ADI and DOX in a rat model of HCC.

METHODS

Experimental HCC was induced in rats by oral administration of diethylnitrosamine. The HCC rats were pretreated with ADI (10 mL/kg, intraperitoneal injection) for 14 consecutive days prior to administration of DOX (7 mg/kg, intravenous injection) to investigate pharmacokinetic interactions. Plasma concentrations of DOX and its major metabolite, doxorubicinol (DOXol), were determined using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

RESULTS

Preadministration of ADI significantly altered the pharmacokinetics of DOX in HCC rats, leading to increased plasma concentrations of both DOX and DOXol. The area under the plasma drug concentration-time curve (AUCs) of DOX and DOXol in rats pretreated with ADI were 3.79-fold and 2.92-fold higher, respectively, than those in control rats that did not receive ADI.

CONCLUSIONS

Increased levels of DOX and DOXol were found in the plasma of HCC rats pretreated with ADI.

TREM-2 defends the liver against hepatocellular carcinoma through multifactorial protective mechanisms

OBJECTIVE

Hepatocellular carcinoma (HCC) is a prevalent and aggressive cancer usually arising on a background of chronic liver injury involving inflammatory and hepatic regenerative processes. The triggering receptor expressed on myeloid cells 2 (TREM-2) is predominantly expressed in hepatic non-parenchymal cells and inhibits Toll-like receptor signalling, protecting the liver from various hepatotoxic injuries, yet its role in liver cancer is poorly defined. Here, we investigated the impact of TREM-2 on liver regeneration and hepatocarcinogenesis.

DESIGN

TREM-2 expression was analysed in liver tissues of two independent cohorts of patients with HCC and compared with control liver samples. Experimental HCC and liver regeneration models in wild type and Trem-2-/- mice, and in vitro studies with hepatic stellate cells (HSCs) and HCC spheroids were conducted.

RESULTS

TREM-2 expression was upregulated in human HCC tissue, in mouse models of liver regeneration and HCC. Trem-2-/- mice developed more liver tumours irrespective of size after diethylnitrosamine (DEN) administration, displayed exacerbated liver damage, inflammation, oxidative stress and hepatocyte proliferation. Administering an antioxidant diet blocked DEN-induced hepatocarcinogenesis in both genotypes. Similarly, Trem-2-/- animals developed more and larger tumours in fibrosis-associated HCC models. Trem-2-/- livers showed increased hepatocyte proliferation and inflammation after partial hepatectomy. Conditioned media from human HSCs overexpressing TREM-2 inhibited human HCC spheroid growth in vitro through attenuated Wnt ligand secretion.

CONCLUSION

TREM-2 plays a protective role in hepatocarcinogenesis via different pleiotropic effects, suggesting that TREM-2 agonism should be investigated as it might beneficially impact HCC pathogenesis in a multifactorial manner.

Protective Role of Vanillic Acid against Diethylnitrosamine- and 1,2-Dimethylhydrazine-Induced Hepatocarcinogenesis in Rats

This study aimed to evaluate the cancer chemopreventive activity of vanillic acid (VA) in diethylnitrosamine- and 1,2-dimethylhydrazine-induced liver and colon carcinogenesis in rats. VA did not induce the formation of hepatic glutathione S-transferase placental form (GST-P) positive foci and colonic aberrant crypt foci, demonstrating no carcinogenic activity. VA (75 mg kg-1 body weight) could significantly reduce the number and areas of hepatic GST-P positive foci when administered before carcinogen injections, but no such effect was seen when it was administered after carcinogen injection. No protection was seen in the colon when VA was treated before or after carcinogen injection. Immunohistochemical studies demonstrated the decreased expression of proliferating cell nuclear antigen and the induction of apoptosis. Mechanistic studies showed that VA significantly induced the expression of GSTA-5 and Nrf-2 genes, which are associated with the detoxification system. Likewise, the antiproliferative effect was noticed by the reduction of Cyclin D1 expression. The apoptotic activity may be due to the upregulation of Caspase-3 and Bad levels and downregulation of the Bcl-2 level. These data suggest that VA exhibited significant protection against diethylnitrosamine- and 1,2-dimethylhydrazine-induced hepatocarcinogenesis, which might be related to the induction of the detoxifying enzyme, the reduction of proliferation and the induction of apoptosis.

Defective apoptotic cell contractility provokes sterile inflammation, leading to liver damage and tumour suppression

Apoptosis is characterized by profound morphological changes, but their physiological purpose is unknown. To characterize the role of apoptotic cell contraction, ROCK1 was rendered caspase non-cleavable (ROCK1nc) by mutating aspartate 1113, which revealed that ROCK1 cleavage was necessary for forceful contraction and membrane blebbing. When homozygous ROCK1nc mice were treated with the liver-selective apoptotic stimulus of diethylnitrosamine, ROCK1nc mice had more profound liver damage with greater neutrophil infiltration than wild-type mice. Inhibition of the damage-associated molecular pattern protein HMGB1 or signalling by its cognate receptor TLR4 lowered neutrophil infiltration and reduced liver damage. ROCK1nc mice also developed fewer diethylnitrosamine-induced hepatocellular carcinoma (HCC) tumours, while HMGB1 inhibition increased HCC tumour numbers. Thus, ROCK1 activation and consequent cell contraction are required to limit sterile inflammation and damage amplification following tissue-scale cell death. Additionally, these findings reveal a previously unappreciated role for acute sterile inflammation as an efficient tumour-suppressive mechanism.

Mild exacerbation of obesity- and age-dependent liver disease progression by senolytic cocktail dasatinib + quercetin

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent and represents a growing challenge in terms of prevention and treatment. A minority of affected patients develops inflammation, subsequently fibrosis, cirrhosis and hepatocellular carcinoma (HCC). HCC is a leading cause of cancer-related death. An increased number of senescent cells correlate with age-related tissue degeneration during NAFLD-induced HCC. Senolytics are promising agents that target selectively senescent cells. Previous studies showed that whereas a combination of the senolytic drugs dasatinib and quercetin (D + Q) reduced NAFLD in mice, D + Q lacked efficacy in removing doxorubicin-induced β-gal-positive senescent cells in human HCC xenografted mice. Whether D + Q has an effect on the age-associated spectrum of NAFLD-inflammation-HCC remains unknown.

METHODS

Here, we utilized an established model of age- and obesity-associated HCC, the low dose diethylnitrosamine (DEN)/high fat diet (HFD), a regimen promoting liver inflammation and tumorigenesis over a long period of 9 months. Four groups of mice each were created: group 1 included control untreated mice; group 2 included mice treated with D + Q; group 3 included mice undergoing the DEN/HFD protocol; group 4 included mice undergoing the DEN/HFD protocol with the administration of D + Q. At the end of the chemical/dietary regimen, we analyzed liver damage and cell senescence by histopathology, qPCR and immunoblotting approaches.

RESULTS

Unexpectedly, D + Q worsened liver disease progression in the DEN/HFD mouse model, slightly increasing histological damage and tumorigenesis, while having no effect on senescent cells removal.

CONCLUSIONS

In summary, using an animal model that fully recapitulates NAFLD, we demonstrate that these compounds are ineffective against age-associated NAFLD-induced HCC. Video Abstract.

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.

Excision of mutagenic replication-blocking lesions suppresses cancer but promotes cytotoxicity and lethality in nitrosamine-exposed mice

N-Nitrosodimethylamine (NDMA) is a DNA-methylating agent that has been discovered to contaminate water, food, and drugs. The alkyladenine DNA glycosylase (AAG) removes methylated bases to initiate the base excision repair (BER) pathway. To understand how gene-environment interactions impact disease susceptibility, we study Aag-knockout (Aag-/-) and Aag-overexpressing mice that harbor increased levels of either replication-blocking lesions (3-methyladenine [3MeA]) or strand breaks (BER intermediates), respectively. Remarkably, the disease outcome switches from cancer to lethality simply by changing AAG levels. To understand the underlying basis for this observation, we integrate a suite of molecular, cellular, and physiological analyses. We find that unrepaired 3MeA is somewhat toxic, but highly mutagenic (promoting cancer), whereas excess strand breaks are poorly mutagenic and highly toxic (suppressing cancer and promoting lethality). We demonstrate that the levels of a single DNA repair protein tip the balance between blocks and breaks and thus dictate the disease consequences of DNA damage.

6-Gingerol, a Major Ingredient of Ginger Attenuates Diethylnitrosamine-Induced Liver Injury in Rats through the Modulation of Oxidative Stress and Anti-Inflammatory Activity

Diethylnitrosamine (DEN) is a well-known hepatocarcinogen, and its oral administration causes severe liver damage including cancer. DEN induces the pathogenesis of the liver through reactive oxygen species mediated inflammation and modulation of various biological activities. 6-Gingerol, a major component of ginger, is reported to prevent liver diseases by reducing the oxidative stress and proinflammatory mediators. The present study investigated the hepatoprotective effects of 6-gingerol through the measurement of oxidative stress, anti-inflammatory markers, liver function enzyme parameter, and histopathological analysis. The rats were randomly divided into four groups as the control, DEN treated (50 mg/kg b.w.), DEN+6-gingerol (each 50 mg/kg b.w.), and 6-gingerol only. To evaluate the hepatoprotective effects, liver function enzymes (ALT, AST, and ALP), oxidative stress markers (SOD, GSH, GST, and TAC), lipid peroxidation, inflammatory markers (CRP, TNF-α, IL-6, and ICAM1), haematoxylin and eosin staining, Sirius red staining, immunohistochemistry, and electron microscopy were performed. The results showed a significant increase in liver function enzymes, oxidative stress, and inflammatory markers in the DEN-treated group as compared to the control group. Besides this, altered architecture of hepatocytes (infiltration of inflammatory cells, congestion, blood vessel dilation, and edema), abundant collagen fiber and organelle structures like distorted shaped and swollen mitochondria, and broken endoplasmic reticulum were noticed. The administration of 6-gingerol significantly ameliorated the biochemical and histopathological changes. The increased expression of TNF-α protein was noticed in the DEN-treated group whereas the administration of 6-gingerol significantly decreased the expression of this protein. Based on these findings, it can be suggested that 6-gingerol may be an alternative therapy for the prevention and treatment of liver diseases.

Inhibitory Effect of Thai Purple Rice Husk Extract on Chemically Induced Carcinogenesis in Rats

This study investigated the cancer chemopreventive effects of an acidic methanol extract of purple rice husk on chemically induced carcinogenesis in rats. This purple rice husk extract (PRHE) had high polyphenol contents. Vanillic acid was a major phenolic compound in PRHE. Three major anthocyanins found in PRHE were malvidin-3-glucoside, peonidin-3-glucoside and cyanidin-3-glucoside. PRHE was not toxic and clastogenic in rats. The LD50 of PRHE was greater than 2000 mg kg-1 body weight (BW). The oral administration of 300 or 1000 mg kg-1 BW of PRHE for 28 days significantly decreased the number of micronucleated hepatocytes in diethylnitrosamine-initiated rats. The inhibitory mechanisms were associated with the reduction of cytochrome P450 2E1 expression and induction of some detoxifying enzymes in the liver. In addition, treatment with 500 mg kg-1 BW of PRHE for eight weeks did not induce preneoplastic lesions in the liver and colon. It significantly inhibited hepatic glutathione-S-transferase positive foci formation induced by diethylnitrosamine and 1,2-dimethylhydrazine by suppression of hepatocyte proliferation and induction of apoptosis. In conclusion, PRHE did not present toxicity, clastogenicity or carcinogenicity in rats. It exhibited cancer chemopreventive properties against chemically induced early stages rat hepatocarcinogenesis. Anthocyanins and vanillic acid might be candidate anticarcinogenic compounds in purple rice husk.

Low-polar extract from seed of Cleistocalyx nervosum var. paniala modulates initiation and promotion stages of chemically-induced carcinogenesis in rats

BACKGROUND

Cleistocalyx nervosum var. paniala is a local fruit mainly cultivated in the north of Thailand. Our previous study has reported that the methanol extract of C. nervosum seed presented antimutagenicity in a Salmonella mutation assay. The present study focused on the effect of a low-polar extract of C. nervosum seed on the early stages of diethylnitrosamine (DEN)- and dimethylhydrazine (DMH)-induced carcinogenesis in rats.

METHODS

Dried C. nervosum seed powder was extracted using dichloromethane. To study its effect on the initiation stage of carcinogenesis of rats, they were fed with various doses of C. nervosum seed extract (CSE) for 21 days. DEN injection was used to initiate hepatocarcinogenesis and partial hepatectomy was performed to amplify mutated hepatocytes resulting in micronucleated hepatocyte formation. To study the role of CSE on the promotion stage, rats were injected with DEN and DMH to induce preneoplastic lesions and the numbers of glutathione S-transferase placental form (GST-P) positive foci in the liver and aberrant crypt foci (ACF) in the colon were measured. This was followed by CSE administration for 10 weeks. The inhibitory mechanisms of CSE on initiation and promotion stages, including xenobiotic metabolism, cell proliferation and apoptosis, were investigated.

RESULTS

The total phenolic content in CSE was 80.34 ± 2.29 mg gallic acid equivalents (GAE) per g of extract and 2,4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone was found to be a major flavonoid. The main terpenoids in CSE were β-selinene, α-selinene, γ-selinene and o-cymene while 24(Z)-methyl-25-homocholesterol was a major phytosterol. CSE significantly decreased the number of micronucleated hepatocytes in DEN-initiated rats and enhanced the activities of hepatic glutathione S-transferase and UDP-glucuronyltransferase. Furthermore, the formation of preneoplastic lesions in the liver and colon was statistically reduced by CSE. CSE also diminished cell proliferation in the liver and colon indicated by the number of PCNA positive cells. However, CSE did not alter the numbers of apoptotic hepatocytes and colonocytes in DEN- and DMH-initiated rats.

CONCLUSIONS

The dichloromethane extract of C. nervosum seed demonstrated chemopreventive effects on chemically-induced carcinogenesis in both initiation and promotion stages in rats. The inhibitory mechanism might be involved in the modulation of hepatic detoxifying enzymes and suppression of hepatocyte and colonocyte proliferation.

Determination of atmospheric amines at Seoul, South Korea via gas chromatography/tandem mass spectrometry

Due to their important roles in salt-producing acid-base reactions, new particle formation (NPF), and as precursors in secondary organic aerosol (SOA) producing reactions, the atmospheric concentrations of particulate volatile amines (dimethylamine (DMA), ethylamine, diethylamine (DEA), propylamine, and butylamine) at Seoul were analyzed and evaluated. To quantify the presence of volatile amines in particulate matter with aerodynamic diameters less than or equal to a nominal 2.5 μm (PM_2.5), an efficient and rapid analytical method based on in-matrix ethyl chloroformate (ECF) derivatization followed by headspace solid-phase microextraction (HS-SPME) was developed and validated using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) in the multiple reaction monitoring (MRM) mode. The annual mean concentration of the total 5 target amines was 5.56±2.76 ng/m³ and the seasonal difference was small. The concentrations of particulate amines measured in this study were lower than those observed in Zongludak, Turkey, Nanjing, China, and Jeju, Korea but slightly higher than that reported in Kobe, Japan. The concentrations of the nitrosamines (nitrosodimethylamine (NDMA) and nitrosodiethylamine (NDEA)), and of the nitramines (dimethylnitramine (DMN) and diethylnitramine (DEN)) measured along with those of the target amines were used in a simple linear regression analysis. It indicates the contribution of DMA to the formation of NDMA in all seasons (except the fall) and DEA to the formation of NDEA in the summer, while DMA and DEA did not significantly contribute to the formation of nitramines.

[Construction of apoptosis-stimulating of p53 protein 2 gene knockout mice and its effect on diethylnitrosamine-induced liver cancer]

Objective: To construct apoptosis-stimulating of p53 protein 2 (ASPP2) gene knockout mice using diethylnitrosamine (DEN)-induced liver cancer model to study the biological functions of ASPP2. Methods: The sgRNA oligonucleotides were constructed, and ASPP2 knockout mice were prepared with the CRISPR/Cas9 system. PCR and sequencing methods were used to identify the genotypes of F0 and F1 generations and their progeny. DEN was used to induce ASPP2+/- mice to establish liver cancer model. Results: PCR and sequencing results showed that ASPP2 gene was successfully knocked out in F0 generation mice. The genotype of F1 generation mice was accorded with ASPP2+/- and had obtained stable heredity. The success rate of DEN-induced liver cancer model (7/8 and 3 / 8) of ASPP2 + /-mice obtained by self-hybridization of F1 generation was significantly higher than that of wild-type mice. Conclusion: ASPP2 knockout mice were successfully constructed based on the CRISPR/Cas9 system. The success rate of DEN-induced liver cancer model of ASPP2 knockout mice was significantly higher than that of the wild-type mice.

Citral inhibits N-nitrosodiethylamine-induced hepatocellular carcinoma via modulation of antioxidants and xenobiotic-metabolizing enzymes

Hepatocellular carcinoma (HCC) ranks the sixth position among various cancers worldwide. Recent research shows that natural and dietary compounds possess many therapeutic effects. Citral is a monoterpene aldehyde that contains geranial and neral. The present study was considered to study the role of citral against N-nitrosodiethylamine (NDEA)-induced HCC via modulation of antioxidants and xenobiotic-metabolizing enzymes in vivo. NDEA-alone-administered group II animals profoundly showed increased tumor incidence, reactive oxygen species, liver marker enzyme levels, serum bilirubin levels, tumor markers of carcinoembryonic antigen, α-fetoprotein, proliferative markers of argyrophilic nucleolar organizing regions, proliferating cell nuclear antigen (PCNA) expressions, phase I xenobiotic-metabolic enzymes and simultaneously decreased antioxidants, and phase II enzymes levels. Citral (100 mg/kg b.w.) treatment significantly reverted the levels in group III cancer-bearing animals when compared to group II cancer-bearing animals. In group IV animals, citral-alone administration did not produce any adverse effect during the experimental condition. Based on the results, citral significantly inhibits the hepatocellular carcinogenesis through restoring the antioxidants and phase II xenobiotic-enzyme levels; thereby, it strongly proves as an antiproliferative agent against rat HCC.

[Inhibitory effect of Biejiajian pills against diethylnitrosamine-induced hepatocarcinogenesis in rats]

OBJECTIVE

To study the inhibitory effect of Biejiajian pills (BJJ) agaisnt diethylnitrosamine (DEN)-induced hepatocarcinogenesis and explore the relation between this effect and the inflammasome signaling pathway.

METHODS

Sixty-five male SD rats were randomly divided into control group, DEN model group, and 3 BJJ treatment groups at low, medium and high dose (with daily dose of 0.55, 1.1 and 2.2 g/kg, respectively, for 12 consecutive weeks starting from the 5th week after modeling). The pathological changes of the liver tissue were observed with HE and Masson staining, and serum levels of alanine transaminase (ALT), glutamic oxaloacetic transaminase (AST), alkaline phosphatase (ALP) and total bilirubin (TBIL) of the rats were detected using ELISA. Oxidation stress in the liver tissue was assessed with ELISA, and Western blotting and ELISA were used to detect the molecular expressions of inflammasome-related pathway.

RESULTS

BJJ significantly inhibited tumor growth in the liver of the rats. HE and Masson staining showed that BJJ treatment obviously ameliorated liver fibrosis and reduced cancer cell and inflammatory cell infiltration in the liver. BJJ significantly reduced elevations of serum ALT, AST, ALP and TBIL levels, increased the contents of superoxide dismutase, catalase and glutathione peroxidase in the liver and suppressed malondialdehyde in Den-treated rats. BJJ also dose-dependently decreased the expressions of NLRP3, apoptosis-associated speck-like protein (ASC), caspase-1, pro-IL-1β, pro-IL-18, IL-1β and IL-18 in the liver of Den-treated rats.

CONCLUSIONS

BJJ treatment can dose-dependently inhibit DEN-induced hepatocarcinogenesis by enhancing antioxidant capacity and down-regulating inflammatory-related pathways in rats.

The potential chemotherapeutic effect of β-ionone and/or sorafenib against hepatocellular carcinoma via its antioxidant effect, PPAR-γ, FOXO-1, Ki-67, Bax, and Bcl-2 signaling pathways

Proliferation and apoptosis are two primary driving forces behind the pathogenesis of hepatocellular carcinoma (HCC). HCC is associated with Ki-67 and Bcl-2 overexpression, reduced Bax expression inducing disturbance of equilibrium between cellular proliferation and apoptosis, and exacerbated by reduced expression of PPAR-γ and FOXO-1. Our objective was to examine the mechanism by which the cyclic isoprenoid, β-ionone (βI), attenuated hepatocarcinogenesis and compare its possible anticancer activity with sorafenib (SF) as standard HCC treatment. HCC induction was achieved by supplying Wistar rats with 0.01% diethylnitrosamine (DENA) for 8 consecutive weeks by free access of drinking water. The effects of βI (160 mg/kg/day) administered orally were evaluated by biochemical, oxidative stress, macroscopical, and histopathological analysis. In addition, immunohistochemical assay for localization and expression of Bax and Bcl-2 and RT-PCR for expression levels of PPAR-γ, FOXO-1, and Ki-67 mRNA were performed. βI treatment significantly reduced the incidence, total number, and multiplicity of visible hepatocyte nodules, attenuated LPO, near-normal restoration of all cancer biomarkers, and antioxidant activities, indicating the chemotherapeutic impact of βI. Histopathological analysis of the liver confirmed that further. βI also induced pro-apoptotic protein Bax expression and reduced anti-apoptotic expression of Bcl-2 protein. Moreover, βI induced mRNA expression of tumor suppressor genes (PPAR-γ and FOXO-1) and decreased proliferative marker Ki-67 mRNA expression. For the first time, the present study provides evidence that βI exerts a major anticancer effect on DENA-induced HCC, at least in part, through inhibition of cell proliferation, oxidative stress, and apoptogenic signal induction mediated by downregulation of Bcl-2 and upregulation of Bax, PPAR-γ, and FOXO-1 expressions.

Administration of Steamed and Freeze-Dried Mature Silkworm Larval Powder Prevents Hepatic Fibrosis and Hepatocellular Carcinogenesis by Blocking TGF-β/STAT3 Signaling Cascades in Rats

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths worldwide and the majority of HCC patients occur with a background of hepatic fibrosis and cirrhosis. We have previously reported the hepatoprotective effects of steamed and freeze-dried mature silkworm larval powder (SMSP) in a chronic ethanol-treated rat model. Here, we assessed the anti-fibrotic and anti-carcinogenic effects of SMSP on diethylnitrosamine (DEN)-treated rats. Wistar rats were intraperitoneally injected with DEN once a week for 12 or 16 weeks with or without SMSP administration (0.1 and 1 g/kg). SMSP administration significantly attenuated tumor foci formation and proliferation in the livers of the rats treated with DEN for 16 weeks. SMSP administration also inhibited hepatic fibrosis by decreasing the levels of collagen fiber and the expression of pro-collagen I and alpha-smooth muscle actin (α-SMA). Moreover, SMSP supplementation improved the major parameters of fibrosis such as transforming growth factor-β (TGF-β), connective tissue growth factor (CTGF), tumor necrosis factor-alpha (TNF-α), plasminogen activator inhibitor-1 (PAI-1), and collagen type I (Col1A1) in the livers from the rats treated with DEN for 16 weeks. As s possible mechanisms, we investigated the effects of SMSP on the TGF-β and signal transducer and activator of transcription 3 (STAT3)-mediated signaling cascades, which are known to promote hepatic fibrosis. We found that SMSP treatment inhibited the activation of TGF-β and the phosphorylation of STAT3 pathway in DEN-treated rats. Moreover, SMSP administration suppressed the expressions of the target genes of TGF-β and STAT3 induced by DEN treatment. Our findings provide experimental evidences that SMSP administration has inhibitory effects of hepatic fibrosis and HCC induced by DEN in vivo and could be a promising strategy for the prevention or treatment of hepatic fibrosis and hepatocellular carcinogenesis.

MiR-30e-3p Influences Tumor Phenotype through MDM2/TP53 Axis and Predicts Sorafenib Resistance in Hepatocellular Carcinoma

The molecular background of hepatocellular carcinoma (HCC) is highly heterogeneous, and biomarkers predicting response to treatments are an unmet clinical need. We investigated miR-30e-3p contribution to HCC phenotype and response to sorafenib, as well as the mutual modulation of TP53/MDM2 pathway, in HCC tissues and preclinical models. MiR-30e-3p was downregulated in human and rat HCCs, and its downregulation associated with TP53 mutations. TP53 contributed to miR-30e-3p biogenesis, and MDM2 was identified among its target genes, establishing an miR-30e-3p/TP53/MDM2 feedforward loop and accounting for miR-30e-3p dual role based on TP53 status. EpCAM, PTEN, and p27 were demonstrated as miR-30e-3p additional targets mediating its contribution to stemness and malignant features. In a preliminary cohort of patients with HCC treated with sorafenib, increased miR-30e-3p circulating levels predicted the development of resistance. In conclusion, molecular background dictates miR-30e-3p dual behavior in HCC. Mdm2 targeting plays a predominant tumor suppressor function in wild-type TP53 contexts, whereas other targets such as PTEN, p27, and EpCAM gain relevance and mediate miR-30e-3p oncogenic role in nonfunctional TP53 backgrounds. Increased circulating levels of miR-30e-3p predict the development of sorafenib resistance in a preliminary series of patients with HCC and deserve future investigations. SIGNIFICANCE: The dual role of miR-30e-3p in HCC clarifies how the molecular context dictates the tumor suppressor or oncogenic function played by miRNAs.

Timp3 deficiency affects the progression of DEN-related hepatocellular carcinoma during diet-induced obesity in mice

AIM

Obesity and low-grade inflammation are associated with an increased risk of hepatocellular carcinoma (HCC), a leading cause of cancer-related death worldwide. The tissue inhibitor of metalloproteinase (TIMP) 3, an endogenous inhibitor of protease activity that represents a key mediator of inflammation, is reduced in inflammatory metabolic disorders and cancer. In contrast, Timp3-deficient mice (Timp3^-/-) are highly resistant to developing HCC in response to a diethylnitrosamine (DEN); therefore, we aimed to elucidate the biological role of genetic loss of Timp3 in obesity-related hepatocarcinogenesis.

METHODS

Fourteen-day-old male wild-type (wt) and Timp3^-/- mice were injected with 25 mg/kg DEN or an equal volume of saline. After 4 weeks, mice were randomized into two dietary groups and fed either normal or high-fat diet and allowed to grow until 32 weeks of age. Liver histological features were analyzed, and differentially expressed genes in the liver were quantified.

RESULTS

In Timp3^-/- mice fed with the obesogenic diet, despite the increase in liver steatosis and inflammation, both the number of tumors and the total tumor size are significantly reduced 30 weeks post-DEN injection, compared to control mice. Moreover, Timp3 deletion in hepatocarcinogenesis during obesity is associated with a reduction in FoxM1 transcriptional activity through H19/miR-675/p53 pathway.

CONCLUSIONS

This study suggests that Timp3 ablation leads to cell cycle perturbation, at least in part by repressing FoxM1 transcriptional activity through H19/miR-675/p53 pathway.

An Immune Gene Expression Signature Associated With Development of Human Hepatocellular Carcinoma Identifies Mice That Respond to Chemopreventive Agents

BACKGROUND & AIMS

Cirrhosis and chronic inflammation precede development of hepatocellular carcinoma (HCC) in approximately 80% of cases. We investigated immune-related gene expression patterns in liver tissues surrounding early-stage HCCs and chemopreventive agents that might alter these patterns to prevent liver tumorigenesis.

METHODS

We analyzed gene expression profiles of nontumor liver tissues from 392 patients with early-stage HCC (training set, N = 167 and validation set, N = 225) and liver tissue from patients with cirrhosis without HCC (N = 216, controls) to identify changes in expression of genes that regulate the immune response that could contribute to hepatocarcinogenesis. We defined 172 genes as markers for this deregulated immune response, which we called the immune-mediated cancer field (ICF). We analyzed the expression data of liver tissues from 216 patients with cirrhosis without HCC and investigated the association between this gene expression signature and development of HCC and outcomes of patients (median follow-up, 10 years). Human liver tissues were also analyzed by histology. C57BL/6J mice were given a single injection of diethylnitrosamine (DEN) followed by weekly doses of carbon tetrachloride to induce liver fibrosis and tumorigenesis. Mice were then orally given the multiple tyrosine inhibitor nintedanib or vehicle (controls); liver tissues were collected and histology, transcriptome, and protein analyses were performed. We also analyzed transcriptomes of liver tissues collected from mice on a choline-deficient high-fat diet, which developed chronic liver inflammation and tumors, orally given aspirin and clopidogrel or the anti-inflammatory agent sulindac vs mice on a chow (control) diet.

RESULTS

We found the ICF gene expression pattern in 50% of liver tissues from patients with cirrhosis without HCC and in 60% of nontumor liver tissues from patients with early-stage HCC. The liver tissues with the ICF gene expression pattern had 3 different features: increased numbers of effector T cells; increased expression of genes that suppress the immune response and activation of transforming growth factor β signaling; or expression of genes that promote inflammation and activation of interferon gamma signaling. Patients with cirrhosis and liver tissues with the immunosuppressive profile (10% of cases) had a higher risk of HCC (hazard ratio, 2.41; 95% confidence interval, 1.21-4.80). Mice with chemically induced fibrosis or diet-induced steatohepatitis given nintedanib or aspirin and clopidogrel down-regulated the ICF gene expression pattern in liver and developed fewer and smaller tumors than mice given vehicle.

CONCLUSIONS

We identified an immune-related gene expression pattern in liver tissues of patients with early-stage HCC, called the ICF, that is associated with risk of HCC development in patients with cirrhosis. Administration of nintedanib or aspirin and clopidogrel to mice with chronic liver inflammation caused loss of this gene expression pattern and development of fewer and smaller liver tumors. Agents that alter immune regulatory gene expression patterns associated with carcinogenesis might be tested as chemopreventive agents in patients with cirrhosis.

Regulation of PKB/Akt-pathway in the chemopreventive effect of lactoferrin against diethylnitrosamine-induced hepatocarcinogenesis in rats

BACKGROUND

Abnormal activation of protein kinase B (PKB) is associated with many cancers. This makes inhibition of PKB signaling pathway a promising strategy for cancer therapy. Lactoferrin (Lf) has been reported for its inhibition of tumor growth and metastasis, however, the mechanism is not completely understood. Its anti-hepatocarcinogenic activity has not taken the deserved recognition despite the additional advantages of Lf as an antiviral against hepatitis C virus, the main cause of hepatocellular carcinoma (HCC), and as a targeting ligand for delivering chemotherapeutics to hepatoma cells.

METHODS

This study evaluated the anti-hepatocarcinogenic effect of Lf, and the role of PKB in this effect using diethylnitrosamine (DENA)-induced HCC rat model, and a primary cell culture prepared from the induced hepatic lesions (DENA-HCC cell culture).

RESULTS

Up-regulation of activated PKB in the hepatocytes of rats with DENA-induced HCC was observed, as measured biochemically in the liver homogenate, and localized immunohistochemically. This was accompanied by increment of hepatocytes proliferation, and expression of vascular endothelial growth factor and endothelial nitric oxide synthase. Involvement of PKB in DENA-induced HCC was confirmed by the observed decrease in cell proliferation in DENA-HCC cell culture that was treated with PKB inhibitor. In Lf-treated rats, a dose-dependent chemopreventive effect was observed, with decreased expression and activation of PKB, amelioration of the other DENA-induced alterations, and stimulation of apoptosis. In vitro, Lf blocked PKB activator-induced cell proliferation.

CONCLUSION

These findings support the chemopreventive activity of Lf against HCC, and suggest regulation of PKB-pathway as a potential mechanism underlying this effect.

Hepatotoxicity and Toxicology of In Vivo Lentiviral Vector Administration in Healthy and Liver-Injury Mouse Models

General safety and toxicology assessments supporting in vivo lentiviral vector-based therapeutic development are sparse. We have previously demonstrated the efficacy of a lentiviral vector expressing fumarylacetoacetate hydrolase (LV-FAH) to cure animal models of hereditary tyrosinemia type 1. Therefore, we performed a complete preclinical toxicological evaluation of LV-FAH, in a large cohort (n = 20/group) of wildtype mice and included matched groups of N-nitrosodiethylamine/carbon tetrachloride (DEN/CCl4)-induced liver injury mice to assess specific toxicity in fibrotic liver tissue. Mice receiving LV-FAH alone (109 TU/mouse) or in combination with DEN/CCl4 presented clinically similar to control animals, with only slight reductions in total body weight gains over the study period (3.2- to 3.7-fold vs. 4.2-fold). There were no indications of toxicity attributed to administration of LV-FAH alone over the duration of this study. The known hepatotoxic combination of DEN/CCl4 induced fibrotic liver injury, and co-administration with LV-FAH was associated with exaggeration of some findings such as an increased liver:body weight ratio and progression to focal hepatocyte necrosis in some animals. Hepatocellular degeneration/regeneration was present in DEN/CCl4-dosed animals regardless of LV-FAH as evaluated by Ki-67 immunohistochemistry and circulating alpha fetoprotein levels, but there were no tumors identified in any tissue in any dose group. These data demonstrate the inherent safety of LV-FAH and support broader clinical development of lentiviral vectors for in vivo administration.

Transketolase Deficiency Protects the Liver from DNA Damage by Increasing Levels of Ribose 5-Phosphate and Nucleotides

De novo nucleotide biosynthesis is essential for maintaining cellular nucleotide pools, the suppression of which leads to genome instability. The metabolic enzyme transketolase (TKT) in the nonoxidative branch of the pentose phosphate pathway (PPP) regulates ribose 5-phosphate (R5P) levels and de novo nucleotide biosynthesis. TKT is required for maintaining cell proliferation in human liver cancer cell lines, yet the role of TKT in liver injury and cancer initiation remains to be elucidated. In this study, we generated a liver-specific TKT knockout mouse strain by crossing TKT^flox/flox mice with albumin-Cre mice. Loss of TKT in hepatocytes protected the liver from diethylnitrosamine (DEN)-induced DNA damage without altering DEN metabolism. DEN treatment of TKT-null liver increased levels of R5P and promoted de novo nucleotide synthesis. More importantly, supplementation of dNTPs in primary hepatocytes alleviated DEN-induced DNA damage, cell death, inflammatory response, and cell proliferation. Furthermore, DEN and high-fat diet (HFD)-induced liver carcinogenesis was reduced in TKT^flox/floxAlb-Cre mice compared with control littermates. Mechanistically, loss of TKT in the liver increased apoptosis, reduced cell proliferation, decreased TNFα, IL6, and STAT3 levels, and alleviated DEN/HFD-induced hepatic steatosis and fibrosis. Together, our data identify a key role for TKT in promoting genome instability during liver injury and tumor initiation. SIGNIFICANCE: These findings identify transketolase as a novel metabolic target to maintain genome stability and reduce liver carcinogenesis.

Compound Astragalus and Salvia miltiorrhiza extract inhibits hepatocellular carcinoma progression via miR-145/miR-21 mediated Smad3 phosphorylation

ETHNOPHARMACOLOGICAL RELEVANCE

Compound Astragalus and Salvia miltiorrhiza extract (CASE), containing astragalosides, astragalus polysaccharide extracted from Astragalus membranaceus (Fisch.) Bge. and salvianolic acids from Salvia miltiorhiza Bge., has been found to inhibit hepatocarcinogenesis via mediating transforming growth factor-β (TGF-β)/Smad signaling, especially Smad3 phosphorylation. The crucial interaction between microRNA-145/microRNA-21 (miR-145/miR-21) and Smad3 phosphorylation is implicated in the pathogenesis and progression of hepatocellular carcinoma (HCC). However, effects of CASE on HCC progression involved in the expression of miR-145/miR-21 and their interaction with Smad3 phosphorylation downstream of TGF-β/MAPK/Smad pathway remain unclear. This study addressed above questions using in vitro (HepG2 cells) and in vivo (Xenografts of nude mice) models of HCC.

MATERIALS AND METHODS

In vivo [Diethylnitrosamine (DEN)-induced HCC in rats] and in vitro [TGF-β₁-stimulated HepG2 cells] models of HCC were established and co-administrated using graded doses/concentrations CASE (60, 120, 240 mg/kg used in rats; 20, 40, 80 µg/ml used in HepG2 cells), miR-145 and miR-21 were measured. HepG2 cells were transfected with miR-145 antagomir, miR-21 agomir and Smad3C/L plasmids (Smad3 EPSM, Smad3 3S-A and Smad3 WT related to up-regulated expression of pSmad3C, pSmad3L and pSmad3C/3L respectively) and then treated by CASE (80 µg/ml). Similarly, HepG2 cell xenografted nude mice were administered with miR-145 antagomir, miR-21 agomir and CASE (310 mg/kg); Smad3 WT, Smad3 EPSM and Smad3 3S-A plasmids stably transfected HepG2 cell lines were constructed respectively and their xenografted nude mice were established, and then treated by CASE (310 mg/kg). Cell proliferation, migration, apoptosis, tumor growth and histopathologic characteristics of xenografts were assessed; also, domain-specific Smad3 phosphorylation isoforms (pSmad3C/pSmad3L), activated MAPKs (pERK1/2, pJNK1/2, pp38) and miR-145, miR-21 were measured.

RESULTS

CASE up-regulated miR-145 while down-regulated miR-21 expression in both rats with DEN-induced HCC and TGF-β₁-stimulated HepG2 cells; CASE inhibited cell migration, proliferation and tumor growth while facilitated cell apoptosis in TGF-β₁-stimulated HepG2 cells and xenografts of nude mice with miR-145 antagomir/miR-21 agomir treatment via increasing miR-145 and facilitating miR-145 modulated pSmad3L→pSmad3C signaling switch while decreasing miR-21 and inhibiting miR-21 modulated MAPK-dependent Smad3L phosphorylation. Also, up-regulated pSmad3C enhanced inhibited effect of CASE on tumor growth and facilitated effect of CASE on cell apoptosis involved in increased miR-145 while decreased miR-21 expression, however, inverse phenomena were observed when up-regulated pSmad3L.

CONCLUSION

Our results suggest that CASE inhibits HCC progression via mediating the interaction of miR-145/miR-21 and Smad3 phosphorylation, especially miR-145/miR-21 mediated Smad3 phosphorylation, which maybe provides an important theoretical foundation for CASE's anti-HCC therapy used for patients in a near future.

Astrocyte Elevated Gene-1 Regulates Macrophage Activation in Hepatocellular Carcinogenesis

Chronic inflammation is a known hallmark of cancer and is central to the onset and progression of hepatocellular carcinoma (HCC). Hepatic macrophages play a critical role in the inflammatory process leading to HCC. The oncogene Astrocyte elevated gene-1 (AEG-1) regulates NFκB activation, and germline knockout of AEG-1 in mice (AEG-1-/-) results in resistance to inflammation and experimental HCC. In this study, we developed conditional hepatocyte- and myeloid cell-specific AEG-1-/- mice (AEG-1ΔHEP and AEG-1ΔMAC, respectively) and induced HCC by treatment with N-nitrosodiethylamine (DEN) and phenobarbital (PB). AEG-1ΔHEP mice exhibited a significant reduction in disease severity compared with control littermates, while AEG-1ΔMAC mice were profoundly resistant. In vitro, AEG-1-/- hepatocytes exhibited increased sensitivity to stress and senescence. Notably, AEG-1-/- macrophages were resistant to either M1 or M2 differentiation with significant inhibition in migration, endothelial adhesion, and efferocytosis activity, indicating that AEG-1 ablation renders macrophages functionally anergic. These results unravel a central role of AEG-1 in regulating macrophage activation and indicate that AEG-1 is required in both tumor cells and tumor microenvironment to stimulate hepatocarcinogenesis.Significance: These findings distinguish a novel role of macrophage-derived oncogene AEG-1 from hepatocellular AEG-1 in promoting inflammation and driving tumorigenesis. Cancer Res; 78(22); 6436-46. ©2018 AACR.

Anti-carcinogenic effect of hesperidin against renal cell carcinoma by targeting COX-2/PGE2 pathway in Wistar rats

The present study was designed to evaluate the protective effects of hesperidin, a flavonoid on DEN initiated and Fe-NTA promoted renal carcinogenesis in Wistar rats. Renal cancer was initiated by a single i.p. injection of DEN (200 mg/kg b.wt.) and promoted with Fe-NTA (9 mg Fe/kg b.wt. i.p.) twice a week for 16 weeks. Rats were simultaneously administered with hesperidin (100 and 200 mg/kg b.wt.) for 16 consecutive weeks. The chemopreventive effect of hesperidin was assessed in terms of antioxidant activities, renal function, PGE2 level, and the expressions of COX-2 and VEGF. Hesperidin decreased the DEN and Fe-NTA induced lipid peroxidation, improved the renal function (by decreasing the levels of BUN, creatinine, and KIM-1) and restored the renal antioxidant armory (GSH, GPx, GR, SOD, and catalase). Hesperidin was also found to decrease the level of PGE2 and downregulate the expressions of COX-2 and VEGF. Histological findings further revealed the protective effects of hesperidin against DEN and Fe-NTA induced kidney damage. The result of our present findings suggest that hesperidin may be a promising modulator in preventing renal cancer possibly by virtue of its ability to alleviate oxidative stress and inhibit COX-2/PGE2 pathway.

Mutational landscape of a chemically-induced mouse model of liver cancer

BACKGROUND & AIMS

Carcinogen-induced mouse models of liver cancer are used extensively to study the pathogenesis of the disease and are critical for validating candidate therapeutics. These models can recapitulate molecular and histological features of human disease. However, it is not known if the genomic alterations driving these mouse tumour genomes are comparable to those found in human tumours. Herein, we provide a detailed genomic characterisation of tumours from a commonly used mouse model of hepatocellular carcinoma (HCC).

METHODS

We analysed whole exome sequences of liver tumours arising in mice exposed to diethylnitrosamine (DEN). Mutational signatures were compared between liver tumours from DEN-treated and untreated mice, and human HCCs.

RESULTS

DEN-initiated tumours had a high, uniform number of somatic single nucleotide variants (SNVs), with few insertions, deletions or copy number alterations, consistent with the known genotoxic action of DEN. Exposure of hepatocytes to DEN left a reproducible mutational imprint in resulting tumour exomes which we could computationally reconstruct using six known COSMIC mutational signatures. The tumours carried a high diversity of low-incidence, non-synonymous point mutations in many oncogenes and tumour suppressors, reflecting the stochastic introduction of SNVs into the hepatocyte genome by the carcinogen. We identified four recurrently mutated genes that were putative oncogenic drivers of HCC in this model. Every neoplasm carried activating hotspot mutations either in codon 61 of Hras, in codon 584 of Braf or in codon 254 of Egfr. Truncating mutations of Apc occurred in 21% of neoplasms, which were exclusively carcinomas supporting a role for deregulation of Wnt/β-catenin signalling in cancer progression.

CONCLUSIONS

Our study provides detailed insight into the mutational landscape of tumours arising in a commonly used carcinogen model of HCC, facilitating the future use of this model to better understand the human disease.

LAY SUMMARY

Mouse models are widely used to study the biology of cancer and to test potential therapies. Herein, we have described the mutational landscape of tumours arising in a carcinogen-induced mouse model of liver cancer. Since cancer is a disease caused by genomic alterations, information about the patterns and types of mutations in the tumours in this mouse model should facilitate its use to study human liver cancer.

Fibrosis-associated hepatocarcinogenesis revisited: Establishing standard medium-term chemically-induced male and female models

Hepatocellular carcinoma causes ~10% of all cancer-related deaths worldwide, usually emerging in a background of liver fibrosis/cirrhosis (70%-90% of cases). Chemically-induced mouse models for fibrosis-associated hepatocarcinogenesis are widely-applied, resembling the corresponding human disease. Nonetheless, a long time is necessary for the development of preneoplastic/neoplastic lesions. Thus, we proposed an early fibrosis-associated hepatocarcinogenesis model for male and female mice separately, focusing on reducing the experimental time for preneoplastic/neoplastic lesions development and establishing standard models for both sexes. Then, two-week old susceptible C3H/HeJ male and female mice (n = 8 animals/sex/group) received a single dose of diethylnitrosamine (DEN, 10 or 50 mg/Kg). During 2 months, mice received 3 weekly doses of carbon tetrachloride (CCl4, 10% corn oil solution, 0.25 to 1.50 μL/g b.wt.) and they were euthanized at week 17. DEN/CCl4 protocols for males and females displayed clear liver fibrosis, featuring collagen accumulation and hepatic stellate cell activation (α-SMA). In addition, liver from males displayed increased CD68+ macrophage number, COX-2 protein expression and IL-6 levels. The DEN/CCl4 models in both sexes impaired antioxidant defense as well as enhanced hepatocyte proliferation and apoptosis. Moreover, DEN/CCl4-treated male and female developed multiple preneoplastic altered hepatocyte foci and hepatocellular adenomas. As expected, the models showed clear male bias. Therefore, we established standard and suitable fibrosis-associated hepatocarcinogenesis models for male and female mice, shortening the experimental time for the development of hepatocellular preneoplastic/neoplastic lesions in comparison to other classical models.

Inhibitory effects of mushroom extracts on progression of carcinogenesis in mice

Hepatocellular carcinoma is a common primary malignancy of hepatocytes that has caused many fatalities globally. To manage the increasing cases of hepatocellular carcinoma, natural products like mushrooms have been tested for their anti-oxidant, anti-tumour and therapeutic properties. This study aimed to investigate the effect of Agaricus bisporus on progression of chemically induced carcinogenesis in mice. Carcinogenesis was induced in experimental and positive group of mice. Development and progression of carcinogenesis was monitored by quantifying levels of Lactate dehydrogenase, total sialic acid and by histological analysis. The results of the study showed that, unlike lactate dehydrogenase, the levels of sialic acid consistently decreased throughout the experimental period in mice that were fed on mushroom extracts compared to the positive control. Histological analysis also showed protection of the hepatocytes from carcinogenesis progression. Overall, the results from tumour markers and histological analysis, showed that addition of Agaricus bisporus extracts to diet slowed down progression of carcinogenesis and these extracts therefore may be useful as supplementary diet to conventional cancer therapies.

Activation of a Ribosomal S6 Protein Kinase in Rapidly Emerging Diethylnitrosamine-Induced Gamma - Glut Amyltranspeptidase-Positive Hyperplastic Liver Lesions of the Rat

The gamma-glutamyl transpeptidase (GGT)-positive hyperplastic liver lesions which developed in the Fisher 344 rat 7 and 60 days following a single carcinogenic dose of diethylnitrosamine (DENA, 200 mg/kg body weight), short-term dietary exposure to 0.02 % 2-acetylaminofluorene (AAF) to suppress the growth of normal hepatocytes, and partial hepatectomy to actuate rapid growth of DENA altered hepatocytes not suppressed by AAF, showed an increased activity of a kinase which specifically phosphorylates the ribosomal S6 protein in vitro. Sham-operated animals showed, on the contrary, no GGT-positive cells and low S6 kinase activity, under the same conditions. After partial hepatectomy, activation of S6 kinase and elevated levels of phosphorylated S6 protein in vitro were detected in the early phases of « normal » hepatocyte proliferation, during liver regeneration, in DENA-treated, GGT-negative preparations, when the « selection » agent AAF was omitted from the diet. The observed activation of S6 kinase in GGT-positive hepatocytes and/or liver nodules could represent an early manifestation of the enhanced proliferation of altered hepatocytes during tumor induction and/or promotion under these conditions.

Sex Comparison of Heme Pathway in Rats Bearing Hepatic Tumors

The present study was undertaken to explore the effect of the presence of hepatic tumors induced by diethylinitrosamine (DENA) on the metabolic heme pathway, and to assess whether these tumors can modify the response of rats to the porphyrinogenic drug hexachlorobenzene (HCB) and whether the above mentioned effects occur to a greater extent in females than males. The results obtained showed that: a) Females were more susceptible to the hepatocarcinogenicity of DENA than males. b) Female normal and DENA treated rats were more susceptible than male rats to the porphyrinogenicity of HCB. c) The presence of hepatic DENA induced tumors could diminish basal hepatic ferrochelatase activity. d) Hepatic tumors could modify the response of animals to a porphyrinogenic drug such as HCB. Thus, both female and male DENA/HBC rats accumulated more porphyrins and showed a lower delta-aminolevulinate synthase and uroporphyrinogen I synthase induction than HCB rats. e) The heme pathway was functional in DENA induced tumors in both male and female rats but they were little affected by HCB.