deoxycholic-acid and Liver-Neoplasms

During the past several decades, the percentage of excess bodyweight and obese adults and children has increased dramatically, and is becoming one of the most serious public health problems worldwide. Extensive epidemiological studies have revealed that there is a strong link between obesity and some common cancers. However, the exact molecular mechanisms linking obesity and cancer are not fully understood yet. Recently, we have reported that dietary or genetic obesity provokes alterations of gut microbiota profile, thereby increasing the levels of deoxycholic acid (DCA), a secondary bile acid produced solely by the 7α-dehydroxylation of primary bile acids carried out by gut bacteria. The enterohepatic circulation of DCA provokes DNA damage and consequent cellular senescence in hepatic stellate cells (HSCs) which, in turn, secrete various inflammatory and tumor-promoting factors in the liver, thus facilitating hepatocellular carcinoma (HCC) development in mice. Interestingly, signs of senescence-associated secretory phenotypes were also observed in the HSCs in the area of HCC arising in patients with nonalcoholic steatohepatitis, implying that a similar pathway is likely to contribute to at least certain aspects of obesity-associated HCC development in humans as well. In this review, I will provide an overview of our recent work and discuss the next steps, focusing on the potential clinical implications of our findings.

Topics: Animals; Carcinogenesis; Carcinoma, Hepatocellular; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Microbiome; Hepatic Stellate Cells; Humans; Liver Neoplasms; Non-alcoholic Fatty Liver Disease; Obesity

It has recently become apparent that obesity is associated with chronic inflammation and several common types of cancer development. Although several events were proposed to be involved in these pathologies, the precise mechanisms underlying obesity-associated inflammation and cancer largely remain unclear. Here, we show that senescence-associated secretory phenotype (SASP) plays crucial roles in promoting obesity-associated hepatocellular carcinoma (HCC) development in mice. Dietary or genetic obesity induces alterations of gut microbiota, thereby increasing the levels of a bacterial metabolite that cause DNA damage. The enterohepatic circulation of the bacterial metabolites provokes SASP phenotype in hepatic stellate cells (HSCs), which in turn, secretes various inflammatory and tumour promoting factors in the liver, thus facilitating HCC development in mice after exposure to chemical carcinogen. Importantly, reducing gut bacteria efficiently prevents HCC development in obese mice. Similar results were also observed in mice lacking an SASP inducer or depleted of senescent HSCs, indicating that the induction of SASP by the gut bacterial metabolite in HSCs plays key roles in obesity-associated HCC development. Interestingly, moreover, signs of SASP were also observed in the HSCs in the area of HCC arising in patients with nonalcoholic steatohepatitis (NASH), implying that a similar pathway may contribute to at least certain aspects of obesity-associated HCC development in humans as well. These findings provide valuable new insights into the development of obesity-associated cancer.

Topics: Animals; Carcinogens; Carcinoma, Hepatocellular; Cellular Senescence; Chronic Disease; Cytokines; Deoxycholic Acid; Digestive System; Hepatic Stellate Cells; Humans; Inflammation; Inflammation Mediators; Liver Neoplasms; Mice; Non-alcoholic Fatty Liver Disease; Obesity

Golgi protein 73 (GP73) is upregulated in a variety of liver diseases, yet the detailed mechanism is poorly characterized. We analyzed GP73 in a retrospective cohort including 4211 patients with chronic liver disease (CLD) or hepatocellular carcinoma (HCC). The effect of deoxycholic acid (DCA) and nuclear factor-kappa B (NF-κB) on expression and release of GP73 in Huh-7 and SMMC7721 cells were studied. A mouse study was used to confirm our findings in vivo. A positive correlation was found between serum GP73 and total bile acid (TBA) in cirrhotic patients (

Topics: Adult; Animals; Bile Acids and Salts; Carcinoma, Hepatocellular; Cell Line, Tumor; Chronic Disease; Deoxycholic Acid; Female; Fibrosis; Gene Expression Profiling; Humans; Liver Cirrhosis; Liver Diseases; Liver Neoplasms; Male; Membrane Proteins; Mice; Mice, Inbred C57BL; Microscopy, Fluorescence; Middle Aged; NF-kappa B p50 Subunit; Phosphoproteins; Retrospective Studies; Up-Regulation

Deoxycholic acid (DCA), a secondary bile acid, is reportedly increased in the serum of patients with nonalcoholic steatohepatitis and animals with experimentally induced hepatocellular carcinoma (HCC), but its contribution to malignant behaviors of HCC has not been precisely clarified. This study aimed to examine the effect of DCA on hepatic stellate cells (HSCs), a major component of nonparenchymal cells in the liver, and its subsequent indirect effect on HCC cells.. LX2 cells, a human HSC line, were treated with DCA in vitro. Then, HuH7 cells, a human hepatoma cell line, were incubated in conditioned media of DCA-treated LX2 to investigate the subsequent effect focusing on malignant behaviors.. DCA resulted in cellular senescence in LX2 with the decreased cell proliferation via cell cycle arrest at G0/1 phase, together with the induction of senescence-associated secretory phenotype (SASP) factors. To investigate the influence of SASP factors secreted by HSCs in response to DCA, HCC cells were treated with conditioned media that promoted cell migration and invasion via induction of epithelial mesenchymal transition. These changes were attenuated in the presence of neutralizing antibody against IL8 or TGFβ. Pathological analysis of surgical specimens from HCC patients revealed that senescent HSCs were detected in the stroma surrounding HCC.. Our data suggest an important role of HSC senescence caused by DCA for the malignant biological behaviors of HCC via induction of SASP factors, particularly IL8 and TGFβ.

Topics: Antibodies, Neutralizing; Carcinoma, Hepatocellular; Cell Movement; Cell Proliferation; Cellular Senescence; Deoxycholic Acid; Epithelial-Mesenchymal Transition; Hepatic Stellate Cells; Humans; Interleukin-8; Liver; Liver Neoplasms; Signal Transduction; Transforming Growth Factor beta

Camptothecin (CPT) is known as an anticancer drug in traditional Chinese medicine. However, due to the lack of targeting, low solubility, and instability of CPT, its therapeutic applications are hampered. Therefore, we synthesized a series of CPT-bile acid analogues that obtained a national patent to improve their tumour-targeting chemotherapeutic effects on liver or colon cancers. Among these analogues, the compound G2 shows high antitumor activity with enhanced liver targeting and improved oral absorption. It is significant to further investigate the possible anticancer mechanism of G2 for its further clinical research and application.. We aimed to unearth the anticancer mechanism of G2 in HepG2 and HCT116 cells.. Cell viability was measured using MTT assay; cell cycle, Mitochondrial Membrane Potential (MMP), and cell apoptosis were detected by flow cytometer; ROS was measured by Fluorescent Microplate Reader; the mRNA and protein levels of cell cycle-related and apoptosis-associated proteins were examined by RT-PCR and western blot, respectively.. We found that G2 inhibited cells proliferation of HepG2 and HCT116 remarkably in a dosedependent manner. Moreover, G2-treatment led to S and G2/M phase arrest in both cells, which could be elucidated by the change of mRNA levels of p21, p27 and Cyclin E and the increased protein level of p21. G2 also induced dramatically ROS accumulated and MMP decreased, which contributed to the apoptosis through activation of both the extrinsic and intrinsic pathways via changing the genes and proteins expression involved in apoptosis pathway in both of HepG2 and HCT116 cells.. These findings suggested that the apoptosis in both cell lines induced by G2 was related to the extrinsic and intrinsic pathways.

Topics: Antineoplastic Agents; Apoptosis; Camptothecin; Cell Cycle; Cell Proliferation; Colonic Neoplasms; Deoxycholic Acid; HCT116 Cells; Hep G2 Cells; Humans; Liver Neoplasms; Membrane Potential, Mitochondrial; Reactive Oxygen Species

Pleurostomophora richardsiae is a dematiaceous mold that causes subcutaneous cystic phaeohyphomycosis. Few cases of invasive P richardsiae infection have been reported. Hepatic artery thrombosis following organ transplantation caused by a fungal organism is also very rare. We present here a 57-year-old man with refractory ascites and liver failure following liver transplantation for treatment of hepatocellular carcinoma. Abdominal computed tomography demonstrated total occlusion of hepatic artery and blood clot in the portal vein and inferior vena cava. P richardsiae was isolated from blood culture and the blood clot in his liver. The patient was treated successfully with a 4-week course of amphotericin B deoxycholate and liver retransplantation.

Topics: Abdomen; Amphotericin B; Antifungal Agents; Ascomycota; Carcinoma, Hepatocellular; Deoxycholic Acid; Drug Combinations; Hepatic Artery; Humans; Liver; Liver Neoplasms; Liver Transplantation; Male; Middle Aged; Phaeohyphomycosis; Portal Vein; Thrombosis; Tomography, X-Ray Computed; Treatment Outcome

Topics: Antineoplastic Agents; Asialoglycoprotein Receptor; Carcinoma, Hepatocellular; Cell Cycle; Cell Movement; Cell Proliferation; Deoxycholic Acid; Drug Delivery Systems; Hep G2 Cells; Human Umbilical Vein Endothelial Cells; Humans; Liver Neoplasms; Magnetic Resonance Spectroscopy; Micelles; Particle Size; Pectins; Sorafenib; Spectroscopy, Fourier Transform Infrared; Tablets; Temperature; Time Factors

Topics: Animals; Antineoplastic Agents, Phytogenic; Carbocyanines; Cell Line, Tumor; Contrast Media; Curcumin; Delayed-Action Preparations; Deoxycholic Acid; Dose-Response Relationship, Drug; Drug Carriers; Drug Compounding; Drug Liberation; Dynamic Light Scattering; Humans; Hydrogen-Ion Concentration; Liver Neoplasms; Mice, Inbred BALB C; Mice, Nude; Microscopy, Electron, Transmission; Molecular Imaging; Nanoparticles; Particle Size; Polyethylene Glycols; Polylysine; Proton Magnetic Resonance Spectroscopy; Technology, Pharmaceutical; Theranostic Nanomedicine; Tissue Distribution; Tumor Burden; Xenograft Model Antitumor Assays

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Hepatocellular; Cell Survival; Chitosan; Deoxycholic Acid; Drug Carriers; Drug Liberation; Ginsenosides; Hep G2 Cells; Humans; Liver Neoplasms; Nanoparticles

Topics: Animals; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Cell Survival; Chitosan; Deoxycholic Acid; Drug Carriers; Female; Folic Acid; Humans; Injections, Intravenous; Liver Neoplasms; MCF-7 Cells; Mice; Micelles; Neoplasm Transplantation; Paclitaxel; Particle Size; Xenograft Model Antitumor Assays

Dysregulated bile acids (BAs) are closely associated with liver diseases and attributed to altered gut microbiota. Here, we show that the intrahepatic retention of hydrophobic BAs including deoxycholate (DCA), taurocholate (TCA), taurochenodeoxycholate (TCDCA), and taurolithocholate (TLCA) were substantially increased in a streptozotocin and high fat diet (HFD) induced nonalcoholic steatohepatitis-hepatocellular carcinoma (NASH-HCC) mouse model. Additionally chronic HFD-fed mice spontaneously developed liver tumors with significantly increased hepatic BA levels. Enhancing intestinal excretion of hydrophobic BAs in the NASH-HCC model mice by a 2% cholestyramine feeding significantly prevented HCC development. The gut microbiota alterations were closely correlated with altered BA levels in liver and feces. HFD-induced inflammation inhibited key BA transporters, resulting in sustained increases in intrahepatic BA concentrations. Our study also showed a significantly increased cell proliferation in BA treated normal human hepatic cell lines and a down-regulated expression of tumor suppressor gene CEBPα in TCDCA treated HepG2 cell line, suggesting that several hydrophobic BAs may collaboratively promote liver carcinogenesis.

Topics: Animals; Bile Acids and Salts; Carcinogenesis; Cell Line; Deoxycholic Acid; Diet, High-Fat; Female; Gastrointestinal Microbiome; Hep G2 Cells; Humans; Liver Neoplasms; Liver Neoplasms, Experimental; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Pregnancy; Streptozocin; Taurochenodeoxycholic Acid; Taurocholic Acid; Taurolithocholic Acid

Topics: Animals; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Liver Neoplasms; Male; Obesity

The hydrophobic bile acid, deoxycholic acid (DC), can induce apoptosis in hepatocytes. The roles of DC and its transporter are not yet established in hepatocellular carcinoma (HCC) cells. We investigated DC-induced alterations in HCC cell growth, with a particular focus on the effect of the expression of bile acid (BA)-transporting Na(+)-dependent taurocholic cotransporting polypeptides (NTCPs).. We determined NTCP expression in four human HCC cell lines: Huh-BAT, Huh-7, SNU-761, and SNU-475. NTCP expression and apoptotic signaling cascades were examined by immunoblot analyses. Cell viability was assessed using the 3,4-(5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt assay. Wound healing and invasion assays were performed to evaluate cell migration and invasion abilities. Real-time polymerase chain reaction was performed to measure IL-8 expression levels. Nuclear factor kappa B (NF-κB) activity was evaluated by enzyme-linked immunosorbent assay.. The HCC cell lines revealed varying NTCP expression levels, and DC treatment had dual effects, depending on NTCP expression. DC induced apoptosis in NTCP-positive HCC cells, especially under hypoxic conditions. In NTCP-negative HCC cells, simultaneous treatment with DC and cyclooxygenase inhibitor markedly decreased aggressive cellular behaviors via the inhibition of NF-κB/COX-2/IL-8 pathways.. Hydrophobic bile acid offers therapeutic potential for patients with advanced HCC via different mechanisms depending on NTCP expression levels within the tumor.

Topics: Apoptosis; Carcinoma, Hepatocellular; Cell Growth Processes; Cell Hypoxia; Cell Line, Tumor; Cyclooxygenase 2; Deoxycholic Acid; Endoplasmic Reticulum Stress; Enzyme Induction; ErbB Receptors; Humans; Interleukin-8; Liver Neoplasms; NF-kappa B; Organic Anion Transporters, Sodium-Dependent; Receptors, G-Protein-Coupled; RNA, Small Interfering; Symporters; Transfection

Topics: Animals; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Liver Neoplasms; Male; Obesity

Topics: Animals; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Liver Neoplasms; Male; Obesity

Topics: Animals; Deoxycholic Acid; Fatty Liver; Humans; Intestines; Liver Neoplasms; Mice; Microbiota

Obesity has become more prevalent in most developed countries over the past few decades, and is increasingly recognized as a major risk factor for several common types of cancer. As the worldwide obesity epidemic has shown no signs of abating, better understanding of the mechanisms underlying obesity-associated cancer is urgently needed. Although several events were proposed to be involved in obesity-associated cancer, the exact molecular mechanisms that integrate these events have remained largely unclear. Here we show that senescence-associated secretory phenotype (SASP) has crucial roles in promoting obesity-associated hepatocellular carcinoma (HCC) development in mice. Dietary or genetic obesity induces alterations of gut microbiota, thereby increasing the levels of deoxycholic acid (DCA), a gut bacterial metabolite known to cause DNA damage. The enterohepatic circulation of DCA provokes SASP phenotype in hepatic stellate cells (HSCs), which in turn secretes various inflammatory and tumour-promoting factors in the liver, thus facilitating HCC development in mice after exposure to chemical carcinogen. Notably, blocking DCA production or reducing gut bacteria efficiently prevents HCC development in obese mice. Similar results were also observed in mice lacking an SASP inducer or depleted of senescent HSCs, indicating that the DCA-SASP axis in HSCs has key roles in obesity-associated HCC development. Moreover, signs of SASP were also observed in the HSCs in the area of HCC arising in patients with non-alcoholic steatohepatitis, indicating that a similar pathway may contribute to at least certain aspects of obesity-associated HCC development in humans as well. These findings provide valuable new insights into the development of obesity-associated cancer and open up new possibilities for its control.

Topics: Animals; Anti-Bacterial Agents; Bacteria; Bile Acids and Salts; Carcinoma, Hepatocellular; Cells, Cultured; Cellular Senescence; Cytokines; Deoxycholic Acid; Dietary Fats; Disease Models, Animal; DNA Damage; Fatty Liver; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Interleukin-1beta; Liver Neoplasms; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Obesity; Phenotype; Risk Factors

Topics: Animals; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Liver Neoplasms; Male; Obesity

Topics: Animals; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Liver Neoplasms; Male; Obesity

Topics: Animals; Cellular Senescence; Deoxycholic Acid; Gastrointestinal Tract; Hepatic Stellate Cells; Humans; Liver Neoplasms; Male; Obesity

Topics: Animals; Deoxycholic Acid; Gastrointestinal Tract; Humans; Liver Neoplasms; Metagenome; Mice; Mice, Obese; Obesity

Ansamycin antibiotics that target heat shock protein 90 function are being developed as anticancer agents but are also known to be dose limiting in patients due to hepatotoxicity. Herein, to better understand how the normal tissue toxicity of geldanamycins could be ameliorated to improve the therapeutic index of these agents, we examined the interactions of 17-allylamino-17-demethoxygeldanamycin (17AAG) and the secondary bile acid deoxycholic acid (DCA) in hepatocytes and fibroblasts. DCA and 17AAG interacted in a greater than additive fashion to cause hepatocyte cell death within 2 to 6 h of coadministration. As single agents DCA, but not 17AAG, enhanced the activity of extracellular signal-regulated kinase 1/2, AKT, c-Jun NH(2)-terminal kinase 1/2 (JNK1/2), and p38 mitogen-activated protein kinase (MAPK). Combined exposure of cells to DCA and 17AAG further enhanced JNK1/2 and p38 MAPK activity. Inhibition of JNK1/2 or p38 MAPK, but not activator protein-1, suppressed the lethality of 17AAG and of 17AAG and DCA. Constitutive activation of AKT, but not MAPK/extracellular signal-regulated kinase kinase 1/2, suppressed 17AAG- and DCA-induced cell killing and reduced activation of JNK1/2. DCA and 17AAG exposure promoted association of BAX with mitochondria, and functional inhibition of BAX or caspase-9, but not of BID and caspase-8, suppressed 17AAG and DCA lethality. DCA and 17AAG interacted in a greater than additive fashion to promote and prolong the generation of reactive oxygen species (ROS). ROS-quenching agents, inhibition of mitochondrial function, expression of dominant-negative thioredoxin reductase, or expression of dominant-negative apoptosis signaling kinase 1 suppressed JNK1/2 and p38 MAPK activation and reduced cell killing after 17AAG and DCA exposure. The potentiation of DCA-induced ROS production by 17AAG was abolished by Ca(2+) chelation and ROS generation, and cell killing following 17AAG and DCA treatment was abolished in cells lacking expression of PKR-like endoplasmic reticulum kinase. Thus, DCA and 17AAG interact to stimulate Ca(2+)-dependent and PKR-like endoplasmic reticulum kinase-dependent ROS production; high levels of ROS promote intense activation of the p38 MAPK and JNK1/2 pathways that signal to activate the intrinsic apoptosis pathway.

Topics: Adenoviridae; Animals; Apoptosis; Benzoquinones; Blotting, Western; Calcium; Carcinoma, Hepatocellular; Ceramides; Deoxycholic Acid; Detergents; Drug Therapy, Combination; Hepatocytes; Humans; Lactams, Macrocyclic; Liver Neoplasms; Male; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinases; Protein Serine-Threonine Kinases; Rats; Rats, Sprague-Dawley; Reactive Nitrogen Species; Reactive Oxygen Species

Hepatitis C virus (HCV) core protein is known to cause oxidative stress and alter apoptosis pathways. However, the apoptosis results are inconsistent, and the real significance of oxidative stress is not well known. The aim of this study was twofold. First, we wanted to confirm whether core-induced oxidative stress was really significant enough to cause DNA damage, and whether it induced cellular antioxidant responses. Second, we wanted to evaluate whether this core-induced oxidative stress and the antioxidant response to it was responsible for apoptosis changes.. HCV core protein was expressed under control of the Tet-Off promoter in Huh-7 cells and HeLa cells. We chose to use deoxycholic acid (DCA) as a model because it is known to produce both reactive oxygen species (ROS) and apoptosis.. Core expression uniformly increased ROS and 8-hydroxy-2'-deoxyguanosine (8-OHdG) under basal and DCA-stimulated conditions. Core protein expression also increased manganese superoxide dismutase levels. Core protein inhibited DCA-mediated mitochondrial membrane depolarization and DCA-mediated activation of caspase-9 and caspase-3, despite the increase in ROS by DCA. Core protein inhibited DCA-mediated apoptosis by increasing Bcl-x(L) protein and decreasing Bax protein, without affecting the proportion of Bax between mitochondria and cytosol, resulting in suppression of cytochrome c release from mitochondria into cytoplasm.. HCV core protein induces oxidative DNA damage, whereas it inhibits apoptosis that is accompanied by enhancement of ROS production. Thus, oxidative stress and apoptosis modulation by core protein are independent of each other.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Antioxidants; Apoptosis; Apoptosis Regulatory Proteins; bcl-2-Associated X Protein; bcl-X Protein; Carcinoma, Hepatocellular; Cell Line, Tumor; Cytochromes c; Cytosol; Dactinomycin; Deoxycholic Acid; Deoxyguanosine; Enzyme Activation; Humans; Intracellular Membranes; Liver Neoplasms; Mitochondria, Liver; Oxidative Stress; Protein Synthesis Inhibitors; Reactive Oxygen Species; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Viral Core Proteins

Topics: Apoptosis; Apoptosis Regulatory Proteins; Carcinoma, Hepatocellular; Cell Line, Tumor; Deoxycholic Acid; Humans; Intracellular Membranes; Liver Neoplasms; Mitochondria, Liver; Oxidative Stress; Reactive Oxygen Species; Viral Core Proteins

Bile acids up-regulate death receptor 5 (DR5)/TRAIL-receptor 2 (TRAIL-R2) expression thereby sensitizing hepatocytes to TRAIL-mediated apoptosis. However, the precise mechanism by which bile acids enhance DR5/TRAIL-R2 expression is unknown. Although several bile acids enhanced DR5/TRAIL-R2 expression, deoxycholic acid (DCA) was the most potent. DCA stimulated JNK activation and the JNK inhibitor SP600125 blocked DCA-induced DR5/TRAIL-R2 mRNA and protein expression. Reporter gene analysis identified a 5'-flanking region containing two Sp1 binding sites within the DR5/TRAIL-R2 promoter as bile acid responsive. Sp1 binding to one of the two sites was enhanced by DCA treatment as evaluated by electrophoretic mobility shift assays and chromatin immunoprecipitation studies. JNK inhibition with SP600125 also blocked binding of Sp1 to the DR5/TRAIL-R2 promoter. Finally, point mutations of the Sp1 binding site attenuated promoter activity. In conclusion, Sp1 is a bile acid-responsive transcription factor that mediates DR5/TRAIL-R2 gene expression downstream of JNK.

Topics: Anthracenes; Base Sequence; Bile Acids and Salts; Binding Sites; Carcinoma, Hepatocellular; Consensus Sequence; Deoxycholic Acid; DNA Primers; Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation; Humans; Liver Neoplasms; Polymerase Chain Reaction; Promoter Regions, Genetic; Receptors, TNF-Related Apoptosis-Inducing Ligand; Receptors, Tumor Necrosis Factor; Sp1 Transcription Factor; Transfection; Tumor Cells, Cultured

The initiating potential of the secondary bile acids, deoxycholic acid (DCA) and lithocholic acid (LCA), was investigated using the development of preneoplastic lesions in the rat liver as a marker. In a short-term assay in which DCA and LCA were given in the diet for 3 weeks in conjunction with partial hepatectomy midway followed by the selection regimen, DCA dose-dependently induced gamma-glutamyltranspeptidase (gamma-GTP)-positive foci, but the results for LCA were less unequivocal and no dose-dependency was evident. In another experiment, I extended the period of observation and examined whether the gamma-GTP-positive foci thus induced by the secondary bile acids can develop into hepatic tumors after a latent period of 52 weeks with or without the administration of phenobarbital (PB), a promoter of experimental hepatocarcinogenesis. Whereas significantly high numbers of hyperplastic liver nodules developed in the DCA-treated rats irrespective of PB promotion, no such increase was evident in the LCA-treated rats. In contrast, both DCA and LCA treatments enhanced the development of glutathione S-transferase placental form (GST-P)-positive foci with or without subsequent PB promotion. The present data indicate that a short period of administration of DCA and LCA in the initiation stage in conjunction with partial hepatectomy results in enhanced development of preneoplastic liver lesions under selection pressure conditions with or without subsequent PB promotion. This suggests that these secondary bile acids possess possible initiating activity for rat hepatocarcinogenesis.

Topics: Animals; Carcinogens; Deoxycholic Acid; gamma-Glutamyltransferase; Hyperplasia; Lithocholic Acid; Liver; Liver Neoplasms; Male; Rats; Rats, Inbred F344

The neoplastic responses of liver to prolonged continuous exposures of deoxycholic acid (DCA) in the diet with or without prior initiation was examined in Fischer 344 (F-344) and Sprague-Dawley (SD) male rats. In both rat strains, 7 months of continuous feeding of 0.5% (F-344 rats) or 1.0% (SD rats) of deoxycholic acid in chow diet generated hepatic nodules which persisted up to 8 months after deoxycholic acid was stopped. In one group of Sprague-Dawley male rats, 7 months of deoxycholic acid was preceded by an initiating dose of diethylnitrosamine. In 10 out of 15 of these rats, not only persistent nodules but also 26 liver cancers (large, multifocal, invasive, lung metastases) become evident by 8 months after cessation of deoxycholic acid.

Topics: Animals; Cocarcinogenesis; Deoxycholic Acid; Diet; Diethylnitrosamine; gamma-Glutamyltransferase; Glutathione Transferase; Liver; Liver Neoplasms; Male; Rats; Rats, Inbred F344; Rats, Inbred Strains

The influence of continuous growth hormone (GH) infusion and of implantation of ectopic pituitary grafts (PG) to male rats on the sex differences (male greater than female) in efficiency of promotion with dietary deoxycholic acid (DCA; 0.5% w/w) was studied in the livers of diethylnitrosamine (DEN)-initiated Wistar rats. For comparison, liver regeneration after partial hepatectomy (PH) was examined in differently treated animals. The endpoints examined included the number and size of enzyme-altered foci, hepatic c-myc expression and liver weight gain. The area per focus was 2- to 3-fold larger in initiated, DCA-treated males than in the corresponding PG-bearing males, GH-treated males and in females. The expression of the c-myc gene was increased approximately 2-fold in initiated and promoted males, while the increase in females was very small. In both groups of hormone-treated males the expression was at the same level as in females, significantly lower than in the corresponding DEN/DCA-treated males. Liver weight gain in response to PH in initiated as well as uninitiated rats of both sexes was significantly stimulated by DCA. No sex differences or effects of PG on regeneration could be discerned. In conclusion, a sex difference, regulated by a pituitary influence, in focal growth and in c-myc expression was observed during DCA promotion of DEN-initiated rats. This might indicate a correlation between the GH-regulated, proliferation-associated c-myc gene and focal growth during sex differentiated promotion in rat liver. Furthermore, the lack of sex differences in liver weight gain in response to PH during DCA treatment suggests that selective mitoinhibition is not involved, and might in this model indicate hormone-dependent selective stimulation of focal growth as a mechanism for tumor promotion.

Topics: Animals; Aryl Hydrocarbon Hydroxylases; Cytochrome P-450 Enzyme System; Deoxycholic Acid; Diethylnitrosamine; Female; Gene Expression; Growth Hormone; Liver; Liver Neoplasms; Liver Regeneration; Male; Organ Size; Pituitary Gland; Proto-Oncogene Proteins c-myc; Rats; Rats, Inbred Strains; RNA Probes; RNA, Messenger; Sex Factors; Steroid Hydroxylases

In vitro treatment of isolated rat hepatocytes with brominated taurodehydrocholic acid (BTC) reduced their sensitivity against phalloidin and inhibited the uptake of phalloidin as well as of cholate in an irreversible and concentration dependent manner. BTC was taken up itself by liver cells; this process was inhibited by 4,4'-diisothiocyano 2,2'-stilbene disulfonate (DIDS). When hepatocytes were incubated with 35S-BTC their plasma membranes contained five labeled protein species with molecular weights of 67,000, 49,000, 38,000, 32,000 and 24,000 as shown by SDS-electrophoresis. No marked difference was observed when isolated plasma membranes from livers were directly treated with the affinity label. DIDS suppressed covalent binding of 35S-BTC to membrane components drastically. Incubation of phalloidin insensitive AS-30D ascites hepatoma cells with 35S-BTC did not result in a chemical modification of the above five proteins. This agrees with an earlier observation that hepatoma cells are unable to take up phalloidin and bile acids (Petzinger et al. 1979; Rufeger and Grundmann 1977; Kroker et al. 1978).

Topics: Affinity Labels; Animals; Carcinoma, Hepatocellular; Cholic Acids; Deoxycholic Acid; In Vitro Techniques; Liver; Liver Neoplasms; Membrane Proteins; Oligopeptides; Phalloidine; Rats; Steroids, Brominated; Sulfur Radioisotopes; Taurodeoxycholic Acid

Bile acids in the spent medium for the cell culture were analyzed by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry to determine whether human hepatoblastoma cell line could synthesize bile acids. Cholic, chenodeoxycholic, and lithocolic acids were found in the culture medium, and a portion of chenodeoxycholic acid and all of lithocholic acid were sulfated. Since the cells had been cultured in serum-free medium, it is clear that the bile acids were newly synthesized and sulfated by the cultured cells. Chenodeoxycholic acid was the main bile acid in the medium, suggesting that the cell line might predominantly synthesize chenodeoxycholic acid. On the other hand, the cells had fetal or hepatoma characters such as marked alpha-fetoprotein production. These results suggest that fetal or hepatoma type bile acid metabolism might occur in the cell line, and that the established cell line could be an useful in vitro model for the study of bile acid metabolism in hepatoma.

Topics: Animals; Bile Acids and Salts; Carcinoma, Hepatocellular; Cell Line; Cells, Cultured; Chenodeoxycholic Acid; Chromatography, Gas; Deoxycholic Acid; Humans; Liver Neoplasms; Rats; Time Factors

Topics: Carcinoma, Hepatocellular; Cell Membrane; Cells, Cultured; Deoxycholic Acid; Fucose; Glycoproteins; Liver Neoplasms; Membrane Proteins; Membranes; Microsomes

The protein in microsomal membranes of hyperplastic nodules of livers from rats fed a diet containing 2-acetyl-aminofluorene referred to as the preneoplastic antigen has been purified to a nearly homogeneous state. A protein sharing identical immunodeterminants based on double agarose diffusion and immunoelectrophoresis has also been detected in deoxycholate-solubilized microsomes from normal liver, but it cannot be detected by gel immunodiffusion in the absence of detergent. There is approximately 4 times as much of this antigen in hyperplastic nodule microsomes as there is in normal microsomes as determined by electroimmunoassay. The antigen from nodules is not more than one-half the molecular weight of the antigen derived from normal microsomes in 0.2% deoxycholate. These findings are consistent with the hypothesis that an altered state of membranes exists in hyperplastic nodule endoplasmic reticulum, resulting in increased amounts of immunoreactive preneoplastic antigen. The nodule protein has a decreased association with its membrane matrix.

Topics: 2-Acetylaminofluorene; Animals; Antigens, Neoplasm; Deoxycholic Acid; Hyperplasia; Immunosorbent Techniques; Liver Neoplasms; Male; Microsomes, Liver; Neoplasms, Experimental; Precancerous Conditions; Rats

A sensitive radioimmunoassay for cholylglycine, chenodeoxycholylglycine, deoxycholylglycine, and sulfolithocholylglycine was established using antibodies obtained from rabbits injected with albumin conjugates of these bile acids. Glycine-conjugated bile acid levels were measured in sera from 25 control subjects and 110 patients who had hepatic disease (alcoholic cirrhosis, hepatitis, cholestasis, and hepatic malignancy). Sulfolithocholylglycine was elevated in the sera of all 110 patients with hepatic disease. Cholylglucine was within normal range in only three. Chenodeoxycholylglycine was elevated in most sera of patients who had hepatitis, cholestasis, or hepatic malignancy. It was normal in most sera of patients who had alcoholic cirrhosis, suggesting that chenodeoxycholic acid may be subject to further biotransformations in these patients. Deoxycholylglycine was elevated in a minority of patients, none of whom had cholestasis. The data suggest that serum bile acids, particularly sulfolithocholylglycine, are a highly sensitive index for hepatic dysfunction.

Topics: Alcoholism; Biliary Tract Diseases; Chenodeoxycholic Acid; Cholestasis; Cholic Acids; Deoxycholic Acid; Glycocholic Acid; Hepatitis; Humans; Lithocholic Acid; Liver Cirrhosis; Liver Diseases; Liver Neoplasms; Radioimmunoassay

The activity of initiation factors obtained from free and membrane-bound polyribosomes of liver and of transplantable H5123 hepatoma of rats was investigated by using an assay of protein synthesis in vitro in which poly (U)-directed polyphenylalanine synthesis was measured. Initiation factors of membrane-bound polyribosomes prepared by using the anionic detergent deoxycholate exhibited less activity in incorporating [14C]phenylalanyltRNA into polypetides than did initiation factors of free polyribosomes. However, when membrane-bound polyribosomes were prepared after using the non-ionic detergent Triton X-100, no significant differences in activities in polyphenylalanine synthesis were observed between the initiation factors of free and membrane-bound polyribosomes. These results suggest that Triton X-100 is preferable to deoxycholate in the isolation of of initiation factors from polyribosomes. Initiation factors, prepared by using Triton X-100, of free polyribosomes of hepatoma exhibited greater activity in the stimulation of polyphenylalanine synthesis than did the initiation factors of free or membrane-bound polyribosomes of host livers or of membrane-bound polyribosomes of hepatomas.

Topics: Animals; Carcinoma, Hepatocellular; Deoxycholic Acid; Female; In Vitro Techniques; Liver; Liver Neoplasms; Membranes; Neoplasms, Experimental; Peptide Biosynthesis; Peptide Initiation Factors; Phenylalanine; Poly U; Polyethylene Glycols; Polyribosomes; Protein Biosynthesis; Rats; Ribosomes; RNA, Transfer

Topics: Animals; Carbon Radioisotopes; Carcinoma, Ehrlich Tumor; Carcinoma, Hepatocellular; Cell Fractionation; Cell Line; Cell Nucleolus; Cell Nucleus; Cells, Cultured; Centrifugation, Density Gradient; Deoxycholic Acid; Electrophoresis, Polyacrylamide Gel; HeLa Cells; Humans; Kidney; L Cells; Liver Neoplasms; Mice; Mice, Inbred Strains; Microscopy, Electron; RNA; RNA, Neoplasm; Sonication; Surface-Active Agents; Uracil Nucleotides

Topics: Animals; Animals, Newborn; Benz(a)Anthracenes; Bile Acids and Salts; Carcinogenesis; Carcinogens; Carcinoma, Hepatocellular; Deoxycholic Acid; Liver Neoplasms; Lung Neoplasms; Methylcholanthrene; Mice; Neoplasms; Neoplasms, Experimental; Pharmacology; Research; Salts