• Molecules and Cells
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• v.38 no.3
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• pp.202-209
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• 2015

Hepatocellular carcinoma (HCC), a highly malignant disease and the third leading cause of all cancer mortalities worldwide, often responses poorly to current treatments and results in dismal outcomes due to frequent chemoresistance and tumor relapse. The heterogeneity of HCC is an important attribute of the disease. It is the outcome of many factors, including the cross-talk between tumor cells within the tumor microenvironment and the acquisition and accumulation of genetic and epigenetic alterations in tumor cells. In addition, there is accumulating evidence in recent years to show that the malignancy of HCC can be attributed partly to the presence of cancer stem cell (CSC). CSCs are capable to self-renew, differentiate and initiate tumor formation. The regulation of the stem cell-like properties by several important signaling pathways have been found to endow the tumor cells with an increased level of tumorigenicity, chemoresistance, and metastatic ability. In this review, we will discuss the recent findings on hepatic CSCs, with special emphasis on their putative origins, relationship with hepatitis viruses, regulatory signaling networks, tumor microenvironment, and how these factors control the stemness of hepatic CSCs. We will also discuss some novel therapeutic strategies targeted at hepatic CSCs for combating HCC and perspectives of future investigation.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.5
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• pp.455-461
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• 2013

Retinoids regulate not only various cell functions including proliferation and differentiation but also glucose and lipid metabolism. After we observed a marked up-regulation of cellular retinol-binding protein-I (CRBP-I) in the liver of hepatitis B virus x antigen (HBx)-transgenic (HBx Tg) mice which are prone to hepatocellular carcinoma (HCC) and fatty liver, we aimed to evaluate retinoid pathway, including genes for the retinoid physiology, CRBP-I protein expression, and retinoid levels, in the liver of HBx Tg mice. We also assessed the effect of chronic metformin treatment on HCC development in the mice. Many genes involved in hepatic retinoid physiology, including CRBP-I, were altered and the tissue levels of retinol and all-trans retinoic acid (ATRA) were elevated in the liver of HBx Tg mice compared to those of wild type (WT) control mice. CRBP-I protein expression in liver, but not in white adipose tissue, of HBx Tg mice was significantly elevated compared to WT control mice while CRBP-I protein expressions in the liver and WAT of high-fat fed obese and db/db mice were comparable to WT control mice. Chronic treatment of HBx Tg mice with metformin did not affect the incidence of HCC, but slightly increased hepatic CRBP-I level. In conclusion, hepatic CRBP-I level was markedly up-regulated in HCC-prone HBx Tg mice and neither hepatic CRBP-I nor the development of HCC was suppressed by metformin treatment.

• The Korean Journal of Cytopathology
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• v.1 no.1
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• pp.1-17
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• 1990

Hepatocellular carcinoma (HCC) is malignant tumor frequently occurring in Koreans. There have been few reports regarding the cytologic findings of fine needle aspiration (FNA) of HCC. Most have suggested a diagnostic problem in the cytology distinguishing HCC from some benign hepatic lesions-for example, a regeneration nodule in cirrhosis and liver cell adenoma. In spite of its high frequency in Korea, no cytologic study has been reported, concerning the FNA of HCC. In an attempt to achieve cytologic criteria for the diagnosis of HCC, the authors studied retrospectively cytopathologic findings of 247 cases of HCC. These cases were confirmed either by histoiogic examination including lobectomy, biopsy, or ceil block material, or, when tissue diagnosis was unavailable, by a high serum alpha-fetoprotein level (over 400 I. U.). All aspiration smears were stained by the Papanicolaou method. In each case, the smears were analyzed for cell patterns and various cytomorphology of the tumor cells. The smear background was assessed for the presence of tumor cell necrosis and inflammatory components and compared to that of metastatic carcinomas. The cell patterns were classified as trabecular, acinar, dispersed, and irregular. The cytologic parameters analyzed included the degree of nuclear atypia and the presence of mitoses, intranuclear cytoplasmic inclusions, nucleolar prominency, endothelial lining, multinucleated giant cells, eosinophiic globules, bile, and Mallory body. Most of the FNA of HCC showed markedly cellular smears. The tumor cells were most frequently arranged in a trabecular pattern (80.3%). The irregular (12.6%), the acinar (5.5%), and the dispersed patterns (1.7%) followed in decreasing frequency. Individual hepatoma cells were larger than normal liver cells. However, they had morphologic features characteristic of the hepatic cells the cells were round or polygonal, their cytoplasm was abundant and granular with eosinophilic or amphophilic stainability, and their nuclei were round to oval, located centrally, and tended to have prominent nucleoli. Anaplasia and pleomorphism of tumor cells were generally mild to moderate. These findings existed even in very well differentiated cases. Mitotic figures were present in about 85% of the cases. Prominent nucleoli were observed only in about half the cases. The frequency of other cytologic features was as follows intranuclear cytoplasmic inclusion in 86.8% : endothelial lining in 56.1% : bile in 19.8% : and giant cells in 60.1%. Clear cells were often present in 11.7%, Most aspiration smears of HCC displayed clean background without necrosis or inflammatory material in contrast to the dirty, necrotic background of metastatic cancers and cholangiocarcinomas. Based on the above mentioned features, it is suqqested that the cytologic critieria most important for the diagnosis of HCC include a markedly cellular smear, trabecular pattern, hepatocytoid appearance of tumor cells, endothelial lining, the presence of bile, giant cells, intranuclear cytoplasmic inclusions, and prominent nucleoli, Among these, trabecular pattern, endothelial lining, giant cells and clean smear background are points to be considered in differentiating HCC from metastatic and cholangiocellular carcinoma.

• Molecular & Cellular Toxicology
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• v.5 no.4
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• pp.317-322
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• 2009

Hepatic fibrosis is one of chronic liver diseases which spread in worldwide and it has high risk to turn advanced cirrhosis and hepatocellualr carcinoma. Brassica family has been produced for commercial purpose and in Korea Brassica rapa (Turnip) is cultivated in Ganghwa County, Gyeonggi-do Korea and used for making Kimchi. Recently pharmacological effects of turnip have been known; diabete mellitus modulation, alcohol oxidization, and fibrosis inhibition. In previous study we found antifibrogenic effect of turnip water extract and in this study we made turnip nanoparticle to promote turnip delivery into liver. At the same time we assessed the biological safety of turnip nanoparticle. Thioacetamide (TAA) induced hepatic nodular formation and fibrosis (mean of fibrosis score: 4). However, 1% turnip nanoparticle inhibited TAA-induced hepatic nodular formation and fibrosis (mean of fibrosis score: 2-3). Activities of serum enzymes (aspartic acid transaminase (AST), alanine transaminase (ALT), and total bilirubin (T-Bil)), complete blood count (CBC), and the appearance of organs were not different from control and 1% turnip nanoparticle treatment. Conclusively 1% turnip nanoparticle significantly reduced TAA-induced hepatic fibrosis and was safe in 7-weeks feeding.

• Korean Journal of Veterinary Pathology
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• v.6 no.1
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• pp.41-48
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• 2002

Oval cell is considered as facultative precursor cells for both hepatocytes and biliary cells, as well as origin of hepatocellar and cholangiocellular carcinoma (CCC) during carcinogenesis or toxic liver injury. To clarify the cellular origin or differentiation of cholagiocarcinogensis, the fate of carcinogen-induced oval cells was pathologically and phenotypically chased in Syrian golden hamster liver after Clonorchis sinensis (CS) infection which would give rise to a promoting effect. Two week treatment of hamsters with 0.005% diethylnitrosamine (DEN) followed by 2 week treatment of 1% 2-acetylaminofluorene (AAF) under choline deficient diet resulted in massive proliferation of BrdU labeleed and PCNA positive oval cells showing various distinct morphology, histochemical and immunohistochemical phenotypes for GGT, cytokeratin 19 and OV-6. Oval cells also frequently form ductular-like structures or phenotypically show hepatocyte-like characteristics. After CS infection, the oval cells showed sequential morphological changes to atypicl proliferating bile ductules and all hamsters thereafter developed well differentiated and anaplastic CCC at 16 week after CS infection. In electron microscopy, some bile ductules were constructed by intermediate oval cells and bile ductular cells surrounded by basement membrane. The results of this study strongly suggest that CCC developed in the present study were originated from hepatic stem-like oval cells, supporting the theory of stem cell origin of cancers. In addition, this hamster model would be valuable for the molecular mechanistic study during chemical-triggered cholangiocarcinogenesis.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.891-900
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• 2004

UDP-N-Acetylglucosamine(GlcNAc):$\beta$1,4-D-mannoside$\beta$-l ,4N-acetylglucosaminyltransferase-III (GnT-III) and UDP-N-GlcNAc:$\alpha$-6-D-mannosid$\beta$-1,6N-acetylglucosaminyltransferase-V(GnT - V) activities were determined in human hepatoma cell lines and metastatic colon cancer cells, and their activities were compared with those of normal liver cells and fetal hepatocytes. GnT-III activities were higher than those of GnT-V in hepatic carcinoma cells. When the two enzyme activities were assayed in highly metastatic colon cancer cells, GnT - V activities were much higher than those of GnT-III. When GlcN, GlcN-biant-PA and UDP-GlcNAc were used as substrates, the enzymes displayed different kinetic properties between hepatic and colon cancer cells, depending on their metastatic potentials. Normal cells of two origins had characteristically very low levels of GnT-III and -V activities, whereas hepatoma and colon cancer cells contained high levels of activities. These data were supported by RT-PCR and Northern blot analyses, showing that the expression of GnT-III and -V mRNAs were increased in proportion to the enzymatic activities. The increased GnT-III, md -V activities were also correlated with increased glycosylation of the cellular glycoproteins in hepatoma and colon cancer cells, as examined by lectin blotting analysis by using wheat germ glutinin (WGA), erythroagglutinating phytohemagglutinin (E-PHA), leukoagglutinating phytohemagglutinin (L-PHA), and concanavalin A (Con A). Treatment with retinoic acid, a differentiation agent, resulted in decreases of both GnT-III and -V activities of HepG2 and HepG3 cells. In colon carcinoma cells, however, treatment with retinoic acid resulted in a reduction of GnT-V activity, but not with GnT-III activity. Although the mechanism underlying the induction of these mzymes is unclear, oligosaccharides in many glycoproteins have been observed of cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.747-752
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• 2013

Oncostatin M (OSM) is a multifunctional cellular regulator acting on a wide variety of cells, which has potential roles in the regulation of gene activation, cell survival, proliferation and differentiation. Previous studies have shown that OSM can induce morphological and/or functional differentiation and maturation of many tumor cells. However, the action of OSM on the induction of differentiation of human hepatocellular carcinoma (HCC) has not been reported. Here, we investigated the effects of different concentrations of OSM on human HCC cell line SMMC-7721 growth, proliferation, cell cycling, apoptosis and differentiation in vitro. Cell growth was determined via MTT assay, proliferation by cell cycle analysis, apoptosis by flow cytometry, morphology by transmission electronic microscopy, and cell function by detection of biochemical markers. Our results demonstrated that OSM strongly inhibited the growth of SMMC-7721 cells in a dose-dependent manner, associated with decreased clonogenicity. Cell cycle analysis revealed a decreased proportion of cells in S phase, with arrest at G0/G1. The apotosis rate was increased after OSM treatment compared to the control. These changes were associated with striking changes in cellular morphology, toward a more mature hepatic phenotype, accompanied by significant reduction of the expression of AFP and specific activity of ${\gamma}$-GT, with remarkable increase in secretion of albumin and ALP activity. Taken together, our findings indicate that OSM could induce the differentiation and reduce cell viability of SMMC-7721 cells, suggesting that differentiation therapy with OSM offers the opportunity for therapeutic intervention in HCC.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3369-3375
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• 2016

MicroRNAs, a novel class of small non-coding RNAs, are key players in many cellular processes, including cell proliferation, differentiation, invasion and regeneration. Tissue and circulatory microRNAs could serve as useful clinical biomarkers and deregulated expression levels have been observed in various cancers. Gene variants may alter microRNA processing and maturation. Thus, we aimed to investigate the association of MIR-196a2 rs11614913 (C/T), MIR-499a rs3746444 (A/G) polymorphisms and their combination with cancer susceptibility in an Egyptian population. Sixty five renal cell carcinoma (RCC) and 60 hepatocellular carcinoma (HCC) patients and 150 controls were enrolled in the study. They were genotyped using real-time polymerase chain reaction technology. Both $miR-196a2^*T$ and $miR-499a*G$ were associated with RCC risk, but only $miR-196a^*T$ was associated with HCC development. Carriage of the homozygote combinations ($MIR196a2^*TT+MIR499a^*AA$) and ($MIR196a2^*CC+MIR499a^*GG$) was associated with 25 and 48 fold elevation of likelhood to develop RCC, respectively. The miR-196a2 SNP was also linked with larger tumor size in RCC and advanced tumor stage in HCC. miR-196a2 and miR-499a combined genotypes were associated with RCC and HCC. Further functional analysis of SNPs is required to confirm relationships between genotypes and phenotypes.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.77-86
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• 2001

Background: Hepatitis C virus(HCV), a family of Flaviviridae, has a host cell-derived envelope containing a positive-stranded RNA genome, and has been known as the maj or etiological agent for chronic hepatitis, hepatic cirrhosis, and hepatocellular carcinoma. There remains a need to dissect a molecular mechanism of pathogenesis for the development of therapeutic and effective preventive measure for HCV. Identification of cellular receptor is of central importance not only to understand the viral pathogenesis, but also to exploit strategies for prevention of HCV. This study was aimed at identifying peptide mimotopes inhibiting the binding of E2 protein of HCV to MOLT-4 cell. Methods: In this study, phage peptide library displaying a random peptides consisting of 7 or 12 random peptides was employed in order to pan against E2 protein. Free HCV particles were separated from the immune complex forms by immunoprecipitation using anti-human IgG antibody, and used for HCV-capture ELISA. To identify the peptides inhibiting E2-binding to MOLT-4 cells, E2 protein was subj ect to bind to MOLT-4 cells under the competition with phage peptides. Results: Several phage peptides were selected for their specific binding to E2 protein, which showed the conserved sequence of SHFWRAP from 3 different peptide sequences. They were also able to recognize the HCV particles in the sera of HCV patients captured by monoclonal antibody against E2 protein. Two of them, showing peptide sequence of HLGPWMSHWFQR and WAPPLERSSLFY respectively, were revealed to inhibit the binding of E2 protein to MOLT-4 cell efficiently in dose dependent mode. However, few membrane-associated receptor candidates were seen using Fasta3 programe for homology search with these peptides. Conclusion: Phage peptides containing HLGPWMSHWFQR and WAPPLERSSLFY respectively, showed the inhibition of E2-binding to MOLT-4 cells. However, they did not reveal any homologues to cellular receptors from GenBank database. In further study, cellular receptor could be identified through the screening of cDNA library from MOLT-4 or hepatocytes using antibodies against these peptide mimotopes.

• Toxicological Research
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• v.8 no.2
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• pp.343-357
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• 1992

Tumor necrosis factor-${\alpha}$(TNF), a polypeptide hormone secreted primarily by activated macrophages, was originally identified on the basis of its ability to cause hemorrhagic necrosis and tumor regression in vivo. Subsequently, TNF has been shown to be an important component of the host responses to infection and cancer and may mediate the wasting syndrome known as cachexia. These systemic actions of TNF are reflected in its diverse effects on target cells in vitro. TNF initiates its diverse cellular actions by binding to specific cell surface receptors. Although TNF receptors have been identified on most of animal cells, regulation of these receptors and the mechanisms which transduce TNF receptor binding into cellular responses are not well understood. Therefore, in the present study, the mechanisms how TNF receptors are being regulated and how TNF receptor binding is being transduced into cellular responses were investigated in rat liver plasma membranes (PM) and ME-180 human cervical carcinoma cell lines. $^{125}I$-TNF bound to high ($K_d=1.51{\pm}0.35nM$)affinity receptors in rat liver PM. Solubilization of PM with 1% Triton X-100 increased both high affinity (from $0.33{\pm}0.04\;to\;1.67{\pm}0.05$ pmoles/mg protein) and low affinity (from $1.92{\pm}0.16\;to\;7.57{\pm}0.50$ pmoles/mg protein) TNF binding without affecting the affinities for TNF, suggesting the presence of a large latent pool of TNF receptors. Affinity labeling of receptors whether from PM or solubilized PM resulted in cross-linking of $^{125}I$-TNF into $M_r$ 130 kDa, 90 kDa and 66kDa complexes. Thus, the properties of the latent TNF receptors were similar to those initially accessible to TNF. To determine if exposure of latent receptors is regulated by TNF, $^{125}I$-TNF binding to control and TNF-pretreated membranes were assayed. Specific binding was increased by pretreatment with TNF (P<0.05), demonstrating that hepatic PM contains latent TNF receptors whose exposure is promoted by TNF. Homologous up-regulation of TNF receptors may, in part, be responsible for sustained hepatic responsiveness during chronic exposure to TNF. As a next step, the post-receptor events induced by TNF were examined. Although the signal transduction pathways for TNF have not been delineated clearly, the actions of many other hormones are mediated by the reversible phosphorylation of specific enzymes or target proteins. The present study demonstrated that TNF induces phosphorylation of 28 kDa protein (p28). Two dimensional soidum dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) resolved the 28kDa phosphoprotein into two isoforms having pIs of 6.2 and 6.1. The pIs and relative molecular weight of p28 were consistent with those of a previously characterized mRNA cap binding protein. mRNA cap binding proteins are a class of translation initiation factors that recognize the 7-methylguanosine cap structure found on the 5' end of eukaryotic mRNAs. In vitro, these proteins are defined by their specific elution from affinity columns composed of 7-methylguanosine 5'-triphosphate($m^7$GTP)-Sepharose. Affinity purification of mRNA cap binding proteins from control and TNF treated ME-180 cells proved that TNF rapidly stimulates phosphorylation of an mRNA cap binding protein. Phosphorylation occurred in several cell types that are important in vitro models of TNF action. The mRNA cap binding protein phosphorylated in response to TNF treatment was purifice, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor-4E(eIF-4E). These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the diverse cellular actions of TNF.