• 한국환경성돌연변이발암원학회지
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• 제23권1호
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• pp.30-34
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• 2003

Recent industrial society has human widely exposed to PAHs (polynuclear aromatic hydrocarbons) that are comming from the incomplete combustion of organic material as wider spread environmental contaminants. Biological activities of PAHs are not known although PAHs are considered as carcinogens. Our laboratory have been studied the effect of PAHs in the mouse liver hepa 1 cells. In this study, we examined the mouse liver hepa-l cells as a new bioassay system to evaluate bioactivity of PAHs. We have selected 13 PAHs to examine bioassay using cyp1a1-luciferase reporter gene expression system where cyp1a1 1.6 Kb 5flanking region DNA was cloned in front of luciferase reporter gene and this plasmid was transfected into hepa 1 cells transiently. This cells then used for the study to observe the effect of PAHs. We demonstrated that PAHs induced the CYP1A1 promoter and 7-ethoxyresolufin O-deethylase (EROD) activities in a concentration-dependant manner. Some of PAHs showed stronger stimulatory effect on CYP1 gene expression than TCDD. Acenaphthene, anthracene, fluorine, naphthalene, pyrene, phenanthrene, carbazole were weak responders to cyp1a1 promoter activity stimulation and EROD induction in hepa 1 cells and these chemicals seemed to respond less to EROD than cyp1a1 promoter activity. Benz(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, chrysene, and dibenzo(a,h)anthracene showed strong response to cyp1a1 promoter activity stimulation and also EROD induction in hepa 1cells. Results of dose response study suggested that four strong responding PAHs, such as benzo(a)anthracene benzo(k)fluoranthene, chrysene, and dibenzo(a, h)anthracene might be mediated through arylhydrocarbon receptor system in hepa1 cells.

• 대한의생명과학회지
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• 제8권3호
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• pp.179-184
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• 2002

We investigated the morphological changes and TUNEL reaction of apoptotic cells in the liver of D-galactosamine (20 mg/mouse) and lipopolysaccharide (5 $\mu\textrm{g}$/mouse)-treated 30 mice (BALB/c), and in additioa also of apoptotic cells in kidney and spleen. The livers and other some organs of mice at 6, 12, 24, 48 and 72 hrs after treatment were collected and were fixed with 10% neutral formalin and paraffin sections were stained with hematoxylin-eosin or terminal deoxynucleotidly transferase-mediated dUTP nick end labeling (TUNEL) method. Morphological changes in apoptotic hepatocytes were chondensation of nuclei and density of cytoplasms, then the margination and pyknosis of chromatin, the formation of half-moon- or horse-shoe- or ship-like shapes of condensed chromatin mass, lastly formation of apoptotic bodies, disappearance of nuclear envelopes, decrease of stainability, then lysis and disappearance of apoptotic bodies. TUNEL positive reactions of hepatocytes were appeared first moderate in uncondensed hepatocytes, severe in condensed hepatocytes, moderate in chromatin-marginated hepatocytes. These reactions also were appeared moderate in hepatocytes with half-moon- or horse-shoe- or ship-like pyknotic chromatin mass or apoptotic bodies, and mild or negative in hepatocytes with lysed apoptotic bodies or with disappeared nuclear envelopes. Consequently these results suggested that TUNEL positive reactions of hepatocytes appeared at more early stages than appearance of chromatin condensation and disappeared at more early stage than disappearance of histological findings of apoptosis. We also confirmed that the differentiation of apoptotic cells from normal healthy cells of Kupffer cells and vascular endothelial cells in liver, reticular cells and lymphocytes in spleen and epithelial cells of tubules and ducts in kidney was impossible in H-E preparations but was possible in TUNEL preparations.

• 대한한의학회지
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• 제24권4호
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• pp.120-126
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• 2003

Object : This study was done to evaluate the inhibitory effect of Samul-tang (Siwu-tang) on collagen production by cultured murine hepatic non-parenchymal cells. Methods : Hepatic non-parenchymal cells were cultured from normal Sprague-Dawley rats and established in a primary cell culture on uncoated plastic culture plates. The Samul-tang (Siwu-tang) was treated into the cell culture media for 72 hours and the cells were harvested for analysis. Analyses were done on cell proliferation, [3H]thymidine incorporation assay and procollagen type IC-peptide. Results : The cultured cells resembled fibroblasts in shape and produced procollagen which is consistent to fibrogenesis in vivo. Proliferation of the non-parenchymal cells was inhibited slightly and the [3H]thymidine incorporation assay showed a dose-dependent decrease by Samul-tang (Siwu-tang) treatment. Production of procollagen type I C-peptide was decreased by low-concentration treatment of the Samul-tang (Siwu-tang), but increased by high-concentration treatment. Conclusion : It seemed that the cells were responding to the Samul-tang (Siwu-tang) in low-concentration, thus producing less collagen. However, when the drug was administered with high enough concentration to cause excessive stimulation of cells, it seemed that the activated cells might overly produce procollagen, the precursor of collagen, thus aggravating fibrosis of the liver. So, it is considered that the proper concentration of Samul-tang (Siwu-tang) is important when treating patients with liver cirrhosis based on the patients' status.

• BMB Reports
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• 제33권3호
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• pp.213-220
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• 2000

A fulminant hepatitis is associated with massive liver cell necrosis and a high mortality rate. But survivors regenerate a normal liver and do not have chronic liver disease. This clinical course suggests that the acutely injured livers release a factor that allows a recovery from chronic hepatitis or cirrhosis. The objective of this study was to isolate and characterize an anti-fibrotic factor from acutely damaged rat livers. The liver cell necrosis was prepared from rat by warm ischemical perfusion and the perfusates were assessed against the growth inhibition of fat-storing cells (FSC). A liver-derived growth inhibitory factor (LDGIF) was purified from ischemically damaged rat livers by chromatographies on Sephacryl S-300, CM Sepharose, hydroxyapatite, and Superose 12. The LDGIF was isolated with an overall purification of 194-fold and 40% recovery. Although LDGIF was identified as the rat liver arginase by Nterminal sequence analysis, LDGIF exists as a monomer and the purified native arginase has a trimer form. Furthermore, LDGIF has a lower enzyme activity on the hydrolysis of L-arginine and a higher inhibitory effect on proliferation of FSC than the normal rat liver arginase. The catalytic activity of LDGIF is ascribed to the monomeric characteristics of the LDGIF. Therefore, the inhibitory action of LDGIF might not be due to the arginine depletion by the catalytic activity of arginase. In conclusion, the presence of the LDGIF could interpret the clinical course that serious fibrosis is not found in the liver of patients recovering from severe hepatic necrosis due to fulminant hepatitis, suggesting that this LDGIF may provide a novel target for the prevention and treatment of hepatic fibrosis.

• BMB Reports
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• 제55권8호
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• pp.401-406
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• 2022

Ahnak, a large protein first identified as an inhibitor of TGF-β signaling in human neuroblastoma, was recently shown to promote TGF-β in some cancers. The TGF-β signaling pathway regulates cell growth, various biological functions, and cancer growth and metastasis. In this study, we used Ahnak knockout (KO) mice that underwent a 70% partial hepatectomy (PH) to investigate the function of Ahnak in TGF-β signaling during liver regeneration. At the indicated time points after PH, we analyzed the mRNA and protein expression of the TGF -β/Smad signaling pathway and cell cycle-related factors, evaluated the cell cycle through proliferating cell nuclear antigen (PCNA) immunostaining, analyzed the mitotic index by hematoxylin and eosin staining. We also measured the ratio of liver tissue weight to body weight. Activation of TGF-β signaling was confirmed by analyzing the levels of phospho-Smad 2 and 3 in the liver at the indicated time points after PH and was lower in Ahnak KO mice than in WT mice. The expression levels of cyclin B1, D1, and E1; proteins in the Rb/E2F transcriptional pathway, which regulates the cell cycle; and the numbers of PCNA-positive cells were increased in Ahnak KO mice and showed tendencies opposite that of TGF-β expression. During postoperative regeneration, the liver weight to body weight ratio tended to increase faster in Ahnak KO mice. However, 7 days after PH, both groups of mice showed similar rates of regeneration, following which their active regeneration stopped. Analysis of hepatocytes undergoing mitosis showed that there were more mitotic cells in Ahnak KO mice, consistent with the weight ratio. Our findings suggest that Ahnak enhances TGF-β signaling during postoperative liver regeneration, resulting in cell cycle disruption; this highlights a novel role of Ahnak in liver regeneration. These results provide new insight into liver regeneration and potential treatment targets for liver diseases that require surgical treatment.

• IMMUNE NETWORK
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• 제13권5호
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• pp.168-176
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• 2013

In the last few years major progress has been made in better understanding the role of natural killer (NK) cells in hepatitis C virus (HCV) infection. This includes multiple pathways by which HCV impairs or limits NK cells activation. Based on current genetic and functional data, a picture is emerging where only a rapid and strong NK cell response early on during infection which results in strong T cell responses and possible subsequent clearance, whereas chronic HCV infection is associated with dysfunctional or biased NK cells phenotypes. The hallmark of this NK cell dysfunction is persistent activation promoting ongoing hepatitis and hepatocyte damage, while being unable to clear HCV due to impaired IFN-${\gamma}$ responses. Furthermore, some data suggests certain chronically activated subsets that are $NKp46^{high}$ may be particularly active against hepatic stellate cells, a key player in hepatic fibrogenesis. Finally, the role of NK cells during HCV therapy, HCV recurrence after liver transplant and hepatocellular carcinoma are discussed.

• 대한세포병리학회지
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• 제19권2호
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• pp.188-193
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• 2008

Angiomyolipoma of the liver is a rare benign tumor that's composed of variable mixtures of adipose tissue, smooth muscle and thick-walled blood vessels. We report here on the imprint cytologic features of a hepatic angiomyolipoma in a 47-year-old man. The smears showed spindle and epithelioid tumor cells in clusters, trabeculae and single cells. The spindle cells had elongated, cigar-shaped nuclei with finely granular chromatin and fibrillary cytoplasm. The epithelioid cells had round nuclei with a moderate amount of cytoplasm. Any adipose tissue was not found. Immunohistochemically, both the spindle and epithelioid cells revealed cytoplasmic positivity for smooth muscle actin and HMB-45.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.915-921
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• 2013

Background: Hepatocellular carcinoma is one of the leading causes of mortalities worldwide. The search for new therapeutic targets is of utmost importance for improved treatment. Altered expression of HDAC1 in hepatocellular carcinoma (HCC) and its requirement for liver formation in zebrafish, suggest that it may regulate key events in liver carcinogenesis and organogenesis. However, molecular mechanisms of HDAC1 action in liver carcinogenesis are largely unknown. The present study was conducted to identify HDAC1 interacting proteins in HepG2 cells using modified SH-double-affinity purification coupled with liquid mass spectrophotemetery. Materials and Methods: HepG2 cells were transfected with a construct containing HDAC1 with a C-terminal strepIII-HA tag as bait. Bait proteins were confirmed to be expressed in HepG2 cells by western blotting and purified by double affinity columns and protein complexes for analysis on a Thermo LTQ Orbitrap XL using a C18 nano flow ESI liquid chromatography system. Results: There were 27 proteins which showed novel interactions with HDAC1 identified only in this study, while 14 were among the established interactors. Various subunits of T complex proteins (TCP1) and prefoldin proteins (PFDN) were identified as interacting partners that showed high affinity with HDAC1 in HepG2 cells. Conclusions: The double affinity purification method adopted in this study was very successful in terms of specificity and reproducibility. The novel HDAC1 complex identified in this study could be better therapeutic target for treatment of hepatocellular carcinoma.

• Toxicological Research
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• 제25권1호
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• pp.23-28
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• 2009

Some of the edible plants like apricot kernel, flaxseed, and cassava generate hydrogen cyanide (HCN) when cyanogenic glycosides are hydrolyzed. Rhodanese (thiosulfate: cyanide sulfurtransferases of TSTs; EC: 2.8.1.1) is a sulfide-detoxifying enzymes that converts cyanides into thiocyanate and sulfite. This enzyme exists in a liver and kidneys in abundance. The present study is to evaluate the conversion of apricot cyanogenic glycosides into thiocyanate by human hepatic (HepG2) and colonal (HT-29) cells, and the induction of the enzymes in the rat. The effects of short term exposure of amygdalin to rats have also been investigated. Cytosolic, mitochondrial, and microsomal fractions from HepG2 and HT-29 cells and normal male Spraque-Dawley rats were used. When apricot kernel extract was used as substrate, the rhodanese activity in liver cells was higher than the activity in colon cells, both from established human cell line or animal tissue. The cytosolic fractions showed the highest rhodanese activity in all of the cells, exhibiting two to three times that of microsomal fractions. Moreover, the cell homogenates could metabolize apricot extract to thiocyanate suggesting cellular hydrolysis of cyanogenic glycoside to cyanide ion, followed by a sulfur transfer to thiocyanate. After the consumption of amygdalin for 14 days, growth of rats began to decrease relative to that of the control group though a significant change in thyroid has not been observed. The resulting data support the conversion to thiocyanate, which relate to the thyroid dysfunction caused by the chronic dietary intake of cyanide. Because Korean eats a lot of Brassicaceae vegetables such as Chinese cabbage and radish, the results of this study might indicate the involvement of rhodanese in prolonged exposure of cyanogenic glycosides.

• 대한수의학회지
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• 제53권2호
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• pp.109-115
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• 2013

Cancers are mainly sustained by a small pool of neoplastic cells, known as cancer stem cells or tumorinitiating cells. These cells possess the ability to self-renew and proliferate, and are thus able to form the tumor. In the present study cells that correspond to cancer stem cells in mammary and liver cancers in animals were identified by the expression of CD133, CD44, CK7, and OCT4 using immunochemistry. As a result, we found with CD133+ and CD44+ cancer stem cell-like phenotypes in mouse and canine hepatocellular carcinoma and canine mammary gland tumors. However, CK7+ and OCT4+ cells were not identified in animal mammary and liver cancer. CD133+ and CD44+ cells are wellknown stem cell lines and play key roles in development and metastasis in human cancer. These findings suggest that cancer stem cells are involved in animal tumorigenesis and may provide insight into mechanisms in cancer development as well as cancer diagnostics.