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Mao Z, Yang X, Mizutani S, Huang Y, Zhang Z, Shinmori H, Gao K, Yao J. Hydrogen Sulfide Mediates Tumor Cell Resistance to Thioredoxin Inhibitor. Front Oncol 2020; 10:252. [PMID: 32219063 PMCID: PMC7078679 DOI: 10.3389/fonc.2020.00252] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 02/13/2020] [Indexed: 12/14/2022] Open
Abstract
Thioredoxin (Trx) is a pro-oncogenic molecule that underlies tumor initiation, progression and chemo-resistance. PX-12, a Trx inhibitor, has been used to treat certain tumors. Currently, factors predicting tumor sensitivity to PX-12 are unclear. Given that hydrogen sulfide (H2S), a gaseous bio-mediator, promotes Trx activity, we speculated that it might affect tumor response to PX-12. Here, we tested this possibility. Exposure of several different types of tumor cells to PX-12 caused cell death, which was reversely correlated with the levels of H2S-synthesizing enzyme CSE and endogenous H2S. Inhibition of CSE sensitized tumor cells to PX-12, whereas addition of exogenous H2S elevated PX-12 resistance. Further experiments showed that H2S abolished PX-12-mediated inhibition on Trx. Mechanistic analyses revealed that H2S stimulated Trx activity. It promoted Trx from the oxidized to the reduced state. In addition, H2S directly cleaved the disulfide bond in PX-12, causing PX-12 deactivation. Additional studies found that, besides Trx, PX-12 also interacted with the thiol residues of other proteins. Intriguingly, H2S-mediated cell resistance to PX-12 could also be achieved through promotion of the thiol activity of these proteins. Addition of H2S-modified protein into culture significantly enhanced cell resistance to PX-12, whereas blockade of extracellular sulfhydryl residues sensitized cells to PX-12. Collectively, our study revealed that H2S mediated tumor cell resistance to PX-12 through multiple mechanisms involving induction of thiol activity in multiple proteins and direct inactivation of PX-12. H2S could be used to predict tumor response to PX-12 and could be targeted to enhance the therapeutic efficacy of PX-12.
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Affiliation(s)
- Zhimin Mao
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Kofu, Japan.,Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, China
| | - Xiawen Yang
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Kofu, Japan
| | - Sayumi Mizutani
- Department of Biotechnology, Faculty of Life and Environmental Sciences, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Kofu, Japan
| | - Yanru Huang
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Kofu, Japan
| | - Zhen Zhang
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Kofu, Japan
| | - Hideyuki Shinmori
- Department of Biotechnology, Faculty of Life and Environmental Sciences, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Kofu, Japan
| | - Kun Gao
- Division of Nephrology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, China
| | - Jian Yao
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Kofu, Japan
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Gleich A, Kaiser B, Honscha W, Fuhrmann H, Schoeniger A. Evaluation of the hepatocyte-derived cell line BFH12 as an in vitro model for bovine biotransformation. Cytotechnology 2019; 71:231-244. [PMID: 30617848 DOI: 10.1007/s10616-018-0279-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 11/08/2018] [Indexed: 12/17/2022] Open
Abstract
The knowledge of drug metabolising enzymes (DMEs) in cattle is rather limited. The capability of the bovine foetal hepatocyte-derived cell line BFH12 to serve as model for biotransformation was evaluated. Gene expression analysis of DMEs was performed by reverse transcription PCR (RT-PCR). The presence of efflux transporters was visualised by immunocytochemistry, and functional induction of cytochrome P450 (CYP) 1A was assessed by the ethoxyresorufin-O-deethylase (EROD) assay. The production of bile acids was measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). RT-PCR revealed the expression of cytochromes 1A1, 1A2, 3A4 and phase II enzymes UGT1A1, UGT1A6 and GSTM1. Immunofluorescence demonstrated efflux transporters ABCG2 and ABCC1. The EROD assay revealed a dose-dependent CYP1A induction after treatment with benzo[a]pyrene (BP). LC-MS/MS analysis of cell culture supernatants showed the production of bile acids including taurocholic acid, tauro-chenodeoxycholic acid, taurodeoxycholic acid and taurolithocholic acid. The results strongly suggest the applicability of the cell line BFH12 for subsequent experiments in the emerging field of bovine biotransformation.
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Affiliation(s)
- Alexander Gleich
- Institute of Biochemistry, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany
| | - Bastian Kaiser
- Institute of Veterinary Physiology, University of Leipzig, An den Tierkliniken 7, 04103, Leipzig, Germany
| | - Walther Honscha
- Institute of Veterinary Pharmacology and Toxicology, University of Leipzig, An den Tierkliniken 15, 04103, Leipzig, Germany
| | - Herbert Fuhrmann
- Institute of Biochemistry, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany
| | - Axel Schoeniger
- Institute of Biochemistry, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany.
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Immortalization and characterization of mouse floxed Bmp2/4 osteoblasts. Biochem Biophys Res Commun 2009; 386:89-95. [PMID: 19501574 DOI: 10.1016/j.bbrc.2009.05.144] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 05/29/2009] [Indexed: 11/20/2022]
Abstract
Generation of a floxed Bmp2/4 osteoblast cell line is a valuable tool for studying the modulatory effects of Bmp2 and Bmp4 on osteoblast differentiation as well as relevant molecular events. In this study, primary floxed Bmp2/4 mouse osteoblasts were cultured and transfected with simian virus 40 large T-antigen. Transfection was verified by polymerase chain reaction (PCR) and immunohistochemistry. To examine the characteristics of the transfected cells, morphology, proliferation and mineralization were analyzed, expression of cell-specific genes including Runx2, ATF4, Dlx3, Osx, dentin matrix protein 1, bone sialoprotein, osteopontin, osteocalcin, osteonectin and collagen type I was detected. These results show that transfected floxed Bmp2/4 osteoblasts bypassed senescence with a higher proliferation rate, but retain the genotypic and phenotypic characteristics similar to the primary cells. Thus, we for the first time demonstrate the establishment of an immortalized mouse floxed Bmp2/4 osteoblast cell line.
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Ma X, Duan Y, Jung CJ, Wu J, VandeVoort CA, Zern MA. The differentiation of hepatocyte-like cells from monkey embryonic stem cells. CLONING AND STEM CELLS 2009; 10:485-93. [PMID: 18795869 DOI: 10.1089/clo.2007.0012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Embryonic stem cells (ESC) hold great potential for the treatment of liver diseases. Here, we report the differentiation of rhesus macaque ESC along a hepatocyte lineage. The undifferentiated monkey ESC line, ORMES-6, was cultured in an optimal culture condition in an effort to differentiate them into hepatocyte-like cells in vitro. The functional efficacy of the differentiated hepatic cells was evaluated using RT-PCR for the expression of hepatocyte specific genes, and Western blot analysis and immunocytochemistry for hepatic proteins such as alpha-fetoprotein (AFP), albumin and alpha1-antitrypsin (alpha1-AT). Functional assays were performed using the periodic acid schiff (PAS) reaction and ELISA. The final yield of ESC-derived hepatocyte-like cells was measured by flow cytometry for cells that were transduced with a liver-specific lentivirus vector containing the alpha1-AT promoter driving the expression of green fluorescence protein (GFP). The treatment of monkey ESC with an optimal culture condition yielded hepatocyte-like cells that expressed albumin, alpha1-AT, AFP, hepatocyte nuclear factor 3beta, glucose-6-phophatase, and cytochrome P450 genes and proteins as determined by RT-PCR and Western blot analysis. Immunofluorescent staining showed the cells positive for albumin, AFP, and alpha1-AT. PAS staining demonstrated that the differentiated cells showed hepatocyte functional activity. Albumin could be detected in the medium after 20 days of differentiation. Flow cytometry data showed that 6.5 +/- 1.0% of the total differentiated cells were positive for GFP. These results suggest that by using a specific, empirically determined, culture condition, we were able to direct monkey ESC toward a hepatocyte lineage.
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Affiliation(s)
- Xiaocui Ma
- Department of Internal Medicine, Transplant Research Program, University of California, Davis Medical Center, Sacramento, California 95817, USA
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5
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Buzzelli MD, Nagarajan M, Radtka JF, Shumate ML, Navaratnarajah M, Lang CH, Cooney RN. Nuclear factor-kappaB mediates the inhibitory effects of tumor necrosis factor-alpha on growth hormone-inducible gene expression in liver. Endocrinology 2008; 149:6378-88. [PMID: 18719026 PMCID: PMC2613053 DOI: 10.1210/en.2007-1574] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
TNF inhibits serine protease inhibitor 2.1 (Spi 2.1) and IGF-I gene expression by GH in CWSV-1 hepatocytes. The current study describes construction of a GH-inducible IGF-I promoter construct and investigates mechanisms by which TNF and nuclear factor-kappaB (NFkappaB) inhibit GH-inducible gene expression. CWSV-1 cells were transfected with GH-inducible Spi 2.1 or IGF-I promoter luciferase constructs, incubated with TNF signaling inhibitors (fumonisin B1 for sphingomyelinase and SP600125 for c-Jun N-terminal kinase), treated with or without TNF, and then stimulated with recombinant human GH. The 5- to 6-fold induction of Spi 2.1 and IGF-I promoter activity by GH was inhibited by TNF. Neither fumonisin B1 nor SP600125 prevented the inhibitory effects of TNF on GH-inducible promoter activity. Dominant-negative inhibitor-kappaBalpha (IkappaBalpha) expression vectors (IkappaBalphaS/A or IkappaBalphaTrunc), p65 and p50 expression vectors, and p65 deletion constructs were used to investigate the NFkappaB pathway. IkappaBalphaS/A and IkappaBalphaTrunc ameliorated the inhibitory effects of TNF on GH-inducible Spi 2.1 and IGF-I promoter activity. Cotransfection of CWSV-1 cells with expression vectors for p65 alone or p50 and p65 together inhibited GH-inducible Spi 2.1 and IGF-I promoter activity. Cotransfection with a C-terminal p65 deletion (1-450) enhanced GH-inducible promoter activity, whereas the N-terminal deletion (31-551) was inhibitory for IGF-I but not Spi 2.1. Cycloheximide did not antagonize the inhibitory effects of TNF on GH-inducible IGF-I expression. We conclude the inhibitory effects of TNF on GH-inducible promoter activity are mediated by NFkappaB, especially p65, by a mechanism that does not require protein synthesis.
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Affiliation(s)
- Mark D Buzzelli
- Department of Surgery, The Pennsylvania State University College of Medicine, 500 University Drive, MCH070, Hershey, Pennsylvania 17033, USA
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6
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Bilello JP, Cable EE, Isom HC. Expression of E-cadherin and other paracellular junction genes is decreased in iron-loaded hepatocytes. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 162:1323-38. [PMID: 12651624 PMCID: PMC1851226 DOI: 10.1016/s0002-9440(10)63928-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Iron overload in the liver may occur in the clinical conditions hemochromatosis and transfusion-dependent thalassemia or by long-term consumption of large amounts of dietary iron. As iron concentrations increase in the liver, cirrhosis develops, and subsequently the normal architecture of the liver deteriorates. The underlying mechanisms whereby iron loading of hepatocytes leads to the pathology of the liver are not understood. Similarly, a direct relationship between the expression levels of paracellular junction genes and altered hepatocellular physiology has been reported; however, no relationship has been identified between iron loading and the expression of paracellular junction genes. Here, we report that the expression of numerous paracellular junction genes was decreased in iron-loaded hepatocytes, leading to increased cellular permeability, increased baculovirus-mediated gene transfer, and decreased gap junction communication. Iron loading of hepatocytes resulted in decreased E-cadherin promoter activity and subsequently decreased E-cadherin mRNA and protein expression. The data presented in this study describe a clear relationship between iron overload and decreased expression of paracellular junction genes in hepatic cells of rat and human origin.
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Affiliation(s)
- John P Bilello
- Department of Microbiology and Immunology, Milton S. Hershey Medical Center, The Penn State College of Medicine, Hershey, Pennsylvania 17033, USA
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Bilello JP, Delaney WE, Boyce FM, Isom HC. Transient disruption of intercellular junctions enables baculovirus entry into nondividing hepatocytes. J Virol 2001; 75:9857-71. [PMID: 11559819 PMCID: PMC114558 DOI: 10.1128/jvi.75.20.9857-9871.2001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2001] [Accepted: 07/09/2001] [Indexed: 01/17/2023] Open
Abstract
Baculovirus infection has extended the capabilities for transfection of exogenous genes into a variety of mammalian cell types. Because rat hepatocytes plated on collagen-coated dishes and maintained in dimethyl sulfoxide (DMSO)-supplemented chemically defined medium are an excellent model system for studying liver function in vitro, we investigated the ability of baculoviruses to infect and deliver exogenous genes to cells in this culture system. Efficient delivery to hepatocytes in short-term culture becomes restricted to peripheral cells, or "edge" cells, as the hepatocytes acquire intercellular junctions and form islands with time in culture. This barrier to baculovirus entry can be overcome, and the percentage of internal cells within the hepatocyte islands that are infected with the baculovirus can be increased more than 100-fold, when cells are subjected to transient calcium depletion before and during infection. These findings suggest that at least in some cell types, such as hepatocytes, baculovirus entry may require contact with the basolateral surface. We conclude from this study that recombinant baculovirus infection following transient depletion of extracellular calcium results in delivery of exogenous genes to at least 75% of hepatocytes in long-term DMSO culture, thereby making it possible for the first time to carry out gain-of-function and loss-of-function studies in this cell system.
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Affiliation(s)
- J P Bilello
- Department of Microbiology and Immunology, Milton S. Hershey Medical Center, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania 17033, USA
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Fukaya K, Asahi S, Nagamori S, Sakaguchi M, Gao C, Miyazaki M, Namba M. Establishment of a human hepatocyte line (OUMS-29) having CYP 1A1 and 1A2 activities from fetal liver tissue by transfection of SV40 LT. In Vitro Cell Dev Biol Anim 2001; 37:266-9. [PMID: 11513080 DOI: 10.1007/bf02577541] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Immortalized human hepatocytes that can retain functions of drug-metabolizing enzymes would be useful for medical and pharmacological studies and for constructing an artificial liver. The aim of this study was to establish immortalized human hepatocyte lines having differentiated liver-specific functions. pSVneo deoxyribonucleic acid, which contains large and small T genes in the early region of simian virus 40, was introduced into hepatocytes that had been obtained from the liver of a 21-wk-old fetus. Neomycin-resistant immortalized colonies were cloned and expanded to mass cultures to examine hepatic functions. Cells were cultured in a chemically defined serum-free medium, ASF104, which contains no peptides other than recombinant human transferrin and insulin. As a result, an immortal human hepatocyte cell line (OUMS-29) having liver-specific functions was established from one of the 13 clones. Expression of CYP 1A1 and 1A2 messenger ribonucleic acid by the cells was induced by treatment with benz[a]pyrene, 3-methylcholanthrene, and benz[a]anthracene. OUMS-29 cells had both the polycyclic aromatic hydrocarbon receptor (AhR) and AhR nuclear translocator. Consequently 7-ethoxyresorufin deethylase activity of the cells was induced time- and dose-dependently by these polycyclic aromatic hydrocarbons. This cell line is expected to be instrumental as an alternative method in animal experiments for studying hepatocarcinogenesis, drug metabolisms of liver cells, and hepatic toxicology.
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Affiliation(s)
- K Fukaya
- Department of Cell Biology, Institute of Cellular and Molecular Biology, Okayama University Medical School, Japan
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9
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Abstract
We demonstrated, using a transient transfection assay, that the albumin enhancer increased the expression of the albumin promoter in a highly differentiated, simian virus 40 (SV40)-immortalized hepatocyte cell line, CWSV1, but was not functional in two ras-transformed cell lines (NR3 and NR4) derived from CWSV1 by stable transfection with the T24ras oncogene. A transient cotransfection assay showed that T24ras and normal c-Ha-ras were each able to inhibit the activity of the albumin enhancer in an immortal hepatocyte cell line. DNase I footprinting and gel mobility shift assays demonstrated that the DNA binding activities specific to the albumin enhancer were not decreased in the ras-transformed cells. ras also did not diminish the expression of HNF1 alpha, C/EBP alpha, HNF3 alpha, HNF3 beta, or HNF3 gamma but did significantly increase AP-1 binding activity. Three AP-1 binding sites were identified within the albumin enhancer, and DNA binding activities specific to these AP-1 sites were induced in the ras-transformed hepatocytes. Subsequent functional assays showed that overexpression of c-jun and c-fos inhibited the activity of the albumin enhancer. Site-directed mutagenesis of the AP-1 binding sites in the albumin enhancer partially abrogated the suppressing effect of ras and c-jun/c-fos on the enhancer. These functional studies therefore supported the results of the structural studies with AP-1. We conclude that the activity of the albumin enhancer is subject to regulation by ras signaling pathways and that the effect of ras on the albumin enhancer activity may be mediated by AP-1.
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Hu J, Isom HC. Suppression of albumin enhancer activity by H-ras and AP-1 in hepatocyte cell lines. Mol Cell Biol 1994; 14:1531-43. [PMID: 8114691 PMCID: PMC358512 DOI: 10.1128/mcb.14.3.1531-1543.1994] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We demonstrated, using a transient transfection assay, that the albumin enhancer increased the expression of the albumin promoter in a highly differentiated, simian virus 40 (SV40)-immortalized hepatocyte cell line, CWSV1, but was not functional in two ras-transformed cell lines (NR3 and NR4) derived from CWSV1 by stable transfection with the T24ras oncogene. A transient cotransfection assay showed that T24ras and normal c-Ha-ras were each able to inhibit the activity of the albumin enhancer in an immortal hepatocyte cell line. DNase I footprinting and gel mobility shift assays demonstrated that the DNA binding activities specific to the albumin enhancer were not decreased in the ras-transformed cells. ras also did not diminish the expression of HNF1 alpha, C/EBP alpha, HNF3 alpha, HNF3 beta, or HNF3 gamma but did significantly increase AP-1 binding activity. Three AP-1 binding sites were identified within the albumin enhancer, and DNA binding activities specific to these AP-1 sites were induced in the ras-transformed hepatocytes. Subsequent functional assays showed that overexpression of c-jun and c-fos inhibited the activity of the albumin enhancer. Site-directed mutagenesis of the AP-1 binding sites in the albumin enhancer partially abrogated the suppressing effect of ras and c-jun/c-fos on the enhancer. These functional studies therefore supported the results of the structural studies with AP-1. We conclude that the activity of the albumin enhancer is subject to regulation by ras signaling pathways and that the effect of ras on the albumin enhancer activity may be mediated by AP-1.
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Affiliation(s)
- J Hu
- Department of Microbiology and Immunology, Pennsylvania State University, College of Medicine, Hershey 17033
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Feldman ST, Gjerset R, Gately D, Chien KR, Feramisco JR. Expression of SV40 virus large T antigen by recombinant adenoviruses activates proliferation of corneal endothelium in vitro. J Clin Invest 1993; 91:1713-20. [PMID: 8386193 PMCID: PMC288151 DOI: 10.1172/jci116381] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Infection with the Ad5-SVR4 virus was used to introduce the large T antigen encoding region of the SV40 virus into bovine and human corneal endothelial cells. Expression of large T antigen occurred in 40% of bovine corneal endothelial cells after a 24-h incubation time versus 12% after 8 h of incubation. By 48 h after infection, almost all (92.8%) bovine corneal endothelial cells expressed large T antigen. Bovine and human corneal endothelial cells which expressed large T antigen proliferated and the characteristic morphologic features of corneal endothelium were maintained. This method may enable growth of enough corneal endothelium to perform studies to elucidate the biochemical mechanisms involved in regulating endothelial cell function.
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Affiliation(s)
- S T Feldman
- Department of Ophthalmology, University of California, San Diego, La Jolla 92093
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Hsu SL, Lin YF, Chou CK. Transcriptional regulation of transferrin and albumin genes by retinoic acid in human hepatoma cell line Hep3B. Biochem J 1992; 283 ( Pt 2):611-5. [PMID: 1315521 PMCID: PMC1131079 DOI: 10.1042/bj2830611] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Transferrin and albumin, which are both secreted from the human hepatoma cell line Hep3B, were regulated transcriptionally by retinoic acid (RA) in a dose-dependent manner. The cell growth rate was little affected under the same conditions. The treatment of Hep3B cells with RA (10 microM for 48 h) resulted in an 8-fold increase in transferrin protein synthesis, a 10-fold increase in the steady-state transferrin mRNA level, and a 5-fold increase in its transcriptional rate. The same treatment led to 4-fold decrease in albumin synthesis, as well as a 7-fold decline in the steady-state albumin mRNA level and a 4-fold decrease in the transcriptional rate. Cycloheximide and actinomycin D blocked the action of RA, suggesting that RA may regulate transferrin and albumin gene expression indirectly in human liver cells.
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Affiliation(s)
- S L Hsu
- Graduate Institute of Microbiology and Immunology, National Yang-Ming Medical College, Taipei, Taiwan, Republic of China
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13
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Fischbach M, Cao HW, Diez Ibanez M, Tsaconas C, Alouani S, Montandon F, el Baraka M, Padieu P, Dreano M, Chessebeuf-Padieu M. Maintenance of liver function in long term culture of hepatocytes following in vitro or in vivo Ha-rasEJ transfection. Cell Biol Toxicol 1991; 7:327-45. [PMID: 1794108 DOI: 10.1007/bf00124069] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Collagenase isolated rat hepatocytes were transfected with liposome encapsulated pEJ (LE-pEJ), a plasmid carrying the human cellular activated Ha-rasEJ oncogene. A proliferative cell line was cloned from these cells transfected in vitro. It secreted per day 0.87 micrograms albumin and 0.32 microgram transferrin per 10(6) cells, and 11.06 nmol free and conjugated bile acids (BA) per mg protein. Also, it metabolized 2-acetylaminofluorene (2-AAF) into N- and ring-hydroxylated metabolites and 2-aminofluorene at rates of 1.50, 9.73, and 1.98 nmol/mg cell protein/24 hr, respectively. Rats were i.v. injected with both LE-pEJ and LE-p17hGHneo carrying the hGH cDNA gene, and secreted hGH in the plasma which induced the synthesis of anti-hGH antibodies. A cell line was cloned from cultures of primary hepatocytes isolated from the liver of transfected rats. After 2 to 3 months in culture, this cell line secreted per day 18.9 micrograms albumin and 11.0 micrograms transferrin per 10(6) cells, 38.75 nmol total BA per mg cell protein, and up to 31 ng hGH per 10(6) cells without cloning hGH recombinant cells. A 24 hr control culture of primary hepatocytes isolated from non transfected rats secreted 25.5 micrograms albumin and 11.7 micrograms transferrin per 10(6) cells, and produced 21.64 nmol total BA and 2.13 nmol N-OH-2-AAF per mg cell protein. Hence, Ha-rasEJ transfection of either hepatocytes in vitro or liver cells in vivo, initiated cell cycles leading to presumptive proliferating hepatocytes which express liver function.
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Affiliation(s)
- M Fischbach
- Laboratoire de Biochimie Médicale, Faculté de Médecine, Université de Bourgogne, Dijon, France
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14
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The mouse albumin enhancer contains a negative regulatory element that interacts with a novel DNA-binding protein. Mol Cell Biol 1990. [PMID: 2370857 DOI: 10.1128/mcb.10.8.3896] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The far-upstream mouse albumin enhancer (-10.5 to -8.43 kilobases) has both positive and negative regulatory domains which contribute to the rate and tissue specificity of albumin gene transcription. (R. S. Herbst, N. Friedman, J. E. Darnell, Jr., and L. E. Babiss, Proc. Natl. Acad. Sci. USA 86:1553-1557). In this work, the negative regulatory region has been functionally localized to sequences -8.7 to -8.43 kilobases upstream of the albumin gene cap site. In the absence of the albumin-modulating region (in which there are binding sites for the transcription factor C/EBP), the negative region can suppress a neighboring positive-acting element, thereby interfering with albumin enhancer function. The negative region is also capable of negating the positive action of the heterologous transthyretin enhancer in an orientation-independent fashion. Within this negative-acting region we can detect two DNA-binding sites, both of which are recognized by a protein present in all cell types tested. This DNA-binding activity is not competed for by any of a series of known DNA-binding sites, and hence this new protein is a candidate for a role in suppressing the albumin gene in nonhepatic cells.
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15
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Herbst RS, Boczko EM, Darnell JE, Babiss LE. The mouse albumin enhancer contains a negative regulatory element that interacts with a novel DNA-binding protein. Mol Cell Biol 1990; 10:3896-905. [PMID: 2370857 PMCID: PMC360900 DOI: 10.1128/mcb.10.8.3896-3905.1990] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The far-upstream mouse albumin enhancer (-10.5 to -8.43 kilobases) has both positive and negative regulatory domains which contribute to the rate and tissue specificity of albumin gene transcription. (R. S. Herbst, N. Friedman, J. E. Darnell, Jr., and L. E. Babiss, Proc. Natl. Acad. Sci. USA 86:1553-1557). In this work, the negative regulatory region has been functionally localized to sequences -8.7 to -8.43 kilobases upstream of the albumin gene cap site. In the absence of the albumin-modulating region (in which there are binding sites for the transcription factor C/EBP), the negative region can suppress a neighboring positive-acting element, thereby interfering with albumin enhancer function. The negative region is also capable of negating the positive action of the heterologous transthyretin enhancer in an orientation-independent fashion. Within this negative-acting region we can detect two DNA-binding sites, both of which are recognized by a protein present in all cell types tested. This DNA-binding activity is not competed for by any of a series of known DNA-binding sites, and hence this new protein is a candidate for a role in suppressing the albumin gene in nonhepatic cells.
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Affiliation(s)
- R S Herbst
- Rockefeller University, New York, New York 10021
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16
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Abstract
Seven simian virus 40 (SV40)-hepatocyte cell lines were characterized with respect to the ability to express eight liver acute-phase genes. cDNA clones corresponding to albumin, serum amyloid A, alpha 1-acid glycoprotein, haptoglobin, alpha-, beta-, and gamma-fibrinogen, and alpha 1-major-acute-phase protein mRNAs were used in Northern (RNA) or slot blot analyses. In the noninduced state, six of the seven cell lines showed significant (i.e., liverlike) levels of constitutive expression of all genes examined except that expression of haptoglobin mRNA was considerable lower than in the normal liver. To examine whether these immortalized liver cells can respond appropriately to inflammatory mediators, cells were treated with conditioned medium from activated human monocytes or mixed lymphocyte cultures. Results showed that these SV40-hepatocyte cell lines responded to the conditioned media in culture by down-regulating albumin gene expression and up-regulating other acute-phase genes in a time- and dose-dependent manner. These results indicate that the SV40-hepatocytes retained not only the ability to express a number of acute-phase genes but also the ability to respond to external stimuli. The usefulness of these cell lines for analysis of the molecular mechanisms involved in the regulation of these acute-phase genes is discussed.
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17
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Liao WS, Ma KT, Woodworth CD, Mengel L, Isom HC. Stimulation of the acute-phase response in simian virus 40-hepatocyte cell lines. Mol Cell Biol 1989; 9:2779-86. [PMID: 2476657 PMCID: PMC362743 DOI: 10.1128/mcb.9.7.2779-2786.1989] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Seven simian virus 40 (SV40)-hepatocyte cell lines were characterized with respect to the ability to express eight liver acute-phase genes. cDNA clones corresponding to albumin, serum amyloid A, alpha 1-acid glycoprotein, haptoglobin, alpha-, beta-, and gamma-fibrinogen, and alpha 1-major-acute-phase protein mRNAs were used in Northern (RNA) or slot blot analyses. In the noninduced state, six of the seven cell lines showed significant (i.e., liverlike) levels of constitutive expression of all genes examined except that expression of haptoglobin mRNA was considerable lower than in the normal liver. To examine whether these immortalized liver cells can respond appropriately to inflammatory mediators, cells were treated with conditioned medium from activated human monocytes or mixed lymphocyte cultures. Results showed that these SV40-hepatocyte cell lines responded to the conditioned media in culture by down-regulating albumin gene expression and up-regulating other acute-phase genes in a time- and dose-dependent manner. These results indicate that the SV40-hepatocytes retained not only the ability to express a number of acute-phase genes but also the ability to respond to external stimuli. The usefulness of these cell lines for analysis of the molecular mechanisms involved in the regulation of these acute-phase genes is discussed.
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Affiliation(s)
- W S Liao
- Department of Biochemistry and Molecular Biology, University of Texas M. D. Anderson Cancer Center, Houston 77030
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18
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Herbst RS, Friedman N, Darnell JE, Babiss LE. Positive and negative regulatory elements in the mouse albumin enhancer. Proc Natl Acad Sci U S A 1989; 86:1553-7. [PMID: 2922398 PMCID: PMC286736 DOI: 10.1073/pnas.86.5.1553] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Most enhancer elements so far described are comprised of multiple DNA binding sites for proteins that act to increase the rate of transcription. In this report we show that the far upstream mouse albumin enhancer element (-10.5 to -8.5 kilobase pairs) is a composite of at least three functional regions: a negative region that suppresses an otherwise positive, liver-specific enhancer element and a third region that by itself is inactive but in conjunction with the remaining elements overrides the effect of the negative region. The protein that binds to the overriding element is C/EBP, a liver-enriched transcription factor, whereas the newly identified protein that is responsible for full liver-specific enhancer activity is found in HeLa cell and spleen extracts as well as in extracts prepared from the liver. This latter protein may therefore be an example of a widely distributed protein that because of cell-specific modification or interaction has a tissue-specific, positive action on transcription.
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Affiliation(s)
- R S Herbst
- Rockefeller University, New York, NY 10021
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19
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Tissue-specific gene expression in mouse hepatocytes cultured in growth-restricting medium. Mol Cell Biol 1989. [PMID: 2463475 DOI: 10.1128/mcb.8.8.3338] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Culture conditions which maintain hepatocytes in their in vivo state are not known. This hampers the study of liver gene expression and of direct responses of liver genes to hormonal stimulation. We argued that hepatocytes that were unable to divide might retain in vivo characteristics. We therefore plated mouse (BALB/c) hepatocytes on plastic dishes in medium lacking arginine and measured the levels and transcription rates of six tissue-specific mRNAs over a period of days. Alpha-fetoprotein mRNA began to accumulate at about 48 h of culture, and transcription could sometimes be detected after 72 h. The levels and transcription rates of four mRNAs (albumin, alpha-1-antitrypsin, apolipoprotein A1, and major urinary protein [MUP]) fell sharply. The rate of transcription of transferrin mRNA fell less rapidly, and its level remained high, partly due to its longer half-life. The overall pattern of gene expression in the plated cells did not exactly parallel that of either fetal or regenerating liver. The hepatocytes remained responsive to hormonal stimulation. Insulin and dexamethasone each tended to counteract changes in mRNA levels, for example, preventing the accumulation of alpha-fetoprotein mRNA. The effects of insulin were primarily due to changes in transcription rates. Bovine growth hormone and thyroxine elevated the levels of most of the mRNAs. Many of the effects of these hormones, when added singly, could not be ascribed to changes in transcription. The level of MUP mRNA was strongly affected by added hormones. The mRNA level at 5 days was increased by added insulin, dexamethasone, growth hormone, and thyroxine. In the presence of these three hormones, the decay in the transcription rate of the MUP genes was reduced about 10-fold. We conclude that hepatocytes plated under these nongrowing conditions can provide insights into the hormonal responsiveness of tissue-specific genes.
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20
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Tumorigenicity of simian virus 40-hepatocyte cell lines: effect of in vitro and in vivo passage on expression of liver-specific genes and oncogenes. Mol Cell Biol 1988. [PMID: 2460744 DOI: 10.1128/mcb.8.10.4492] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Five simian virus 40 (SV40)-hepatocyte cell lines were examined for tumorigenicity and the effect of in vitro passage on the expression of four liver-specific genes (albumin, transferrin, alpha 1-antitrypsin, and phosphoenolpyruvate carboxykinase), two oncogenes (c-Ha-ras and c-raf), and two genes associated with hepatocarcinogenesis (alpha-fetoprotein and placental-type glutathione-S-transferase). At low passage (12 to 22), all five cell lines expressed the four liver-specific genes at levels similar to those in the liver and were not tumorigenic or were weakly tumorigenic. At high passage (33 to 61), the cell lines formed carcinomas, and four out of five cell lines produced primary tumors that metastasized. At least two cell lines produced well-differentiated hepatocellular carcinomas that expressed liver-specific RNAs. Levels of expression of liver-specific genes changed with time in culture. Some of the changes in liver-specific gene expression in the tumor tissue (such as for the phosphoenolpyruvate carboxykinase gene) paralleled those that occurred with in vitro passage, while other changes (such as for the albumin gene) did not parallel those that occurred with in vitro passage. Correlations between enhanced expression of c-Ha-ras and tumorigenic potential and between the process of SV40 immortalization and induced expression of c-raf and glutathione-S-transferase-P were observed. Induction of alpha-fetoprotein was detected with in vitro and in vivo passage only in the CWSV14 cell line and was paralleled by diminished albumin expression. In conclusion, we developed a model system with five SV40-hepatocyte cell lines, tumors induced by them, and tumor cell lines to examine changes in gene expression that accompany the progression from a normal cell to a hepatocellular carcinoma. Because the SV40-hepatocyte cell lines and tumor cell lines remain highly differentiated and vary in the magnitude of expression of specific genes, they can be used to study the molecular mechanisms regulating gene expression, in particular those regulating specific genes associated with differentiation.
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21
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Woodworth CD, Kreider JW, Mengel L, Miller T, Meng YL, Isom HC. Tumorigenicity of simian virus 40-hepatocyte cell lines: effect of in vitro and in vivo passage on expression of liver-specific genes and oncogenes. Mol Cell Biol 1988; 8:4492-501. [PMID: 2460744 PMCID: PMC365524 DOI: 10.1128/mcb.8.10.4492-4501.1988] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Five simian virus 40 (SV40)-hepatocyte cell lines were examined for tumorigenicity and the effect of in vitro passage on the expression of four liver-specific genes (albumin, transferrin, alpha 1-antitrypsin, and phosphoenolpyruvate carboxykinase), two oncogenes (c-Ha-ras and c-raf), and two genes associated with hepatocarcinogenesis (alpha-fetoprotein and placental-type glutathione-S-transferase). At low passage (12 to 22), all five cell lines expressed the four liver-specific genes at levels similar to those in the liver and were not tumorigenic or were weakly tumorigenic. At high passage (33 to 61), the cell lines formed carcinomas, and four out of five cell lines produced primary tumors that metastasized. At least two cell lines produced well-differentiated hepatocellular carcinomas that expressed liver-specific RNAs. Levels of expression of liver-specific genes changed with time in culture. Some of the changes in liver-specific gene expression in the tumor tissue (such as for the phosphoenolpyruvate carboxykinase gene) paralleled those that occurred with in vitro passage, while other changes (such as for the albumin gene) did not parallel those that occurred with in vitro passage. Correlations between enhanced expression of c-Ha-ras and tumorigenic potential and between the process of SV40 immortalization and induced expression of c-raf and glutathione-S-transferase-P were observed. Induction of alpha-fetoprotein was detected with in vitro and in vivo passage only in the CWSV14 cell line and was paralleled by diminished albumin expression. In conclusion, we developed a model system with five SV40-hepatocyte cell lines, tumors induced by them, and tumor cell lines to examine changes in gene expression that accompany the progression from a normal cell to a hepatocellular carcinoma. Because the SV40-hepatocyte cell lines and tumor cell lines remain highly differentiated and vary in the magnitude of expression of specific genes, they can be used to study the molecular mechanisms regulating gene expression, in particular those regulating specific genes associated with differentiation.
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Affiliation(s)
- C D Woodworth
- Department of Microbiology and Immunology, Pennsylvania State University College of Medicine, Hershey 17033
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22
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Spiegelberg T, Bishop JO. Tissue-specific gene expression in mouse hepatocytes cultured in growth-restricting medium. Mol Cell Biol 1988; 8:3338-44. [PMID: 2463475 PMCID: PMC363569 DOI: 10.1128/mcb.8.8.3338-3344.1988] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Culture conditions which maintain hepatocytes in their in vivo state are not known. This hampers the study of liver gene expression and of direct responses of liver genes to hormonal stimulation. We argued that hepatocytes that were unable to divide might retain in vivo characteristics. We therefore plated mouse (BALB/c) hepatocytes on plastic dishes in medium lacking arginine and measured the levels and transcription rates of six tissue-specific mRNAs over a period of days. Alpha-fetoprotein mRNA began to accumulate at about 48 h of culture, and transcription could sometimes be detected after 72 h. The levels and transcription rates of four mRNAs (albumin, alpha-1-antitrypsin, apolipoprotein A1, and major urinary protein [MUP]) fell sharply. The rate of transcription of transferrin mRNA fell less rapidly, and its level remained high, partly due to its longer half-life. The overall pattern of gene expression in the plated cells did not exactly parallel that of either fetal or regenerating liver. The hepatocytes remained responsive to hormonal stimulation. Insulin and dexamethasone each tended to counteract changes in mRNA levels, for example, preventing the accumulation of alpha-fetoprotein mRNA. The effects of insulin were primarily due to changes in transcription rates. Bovine growth hormone and thyroxine elevated the levels of most of the mRNAs. Many of the effects of these hormones, when added singly, could not be ascribed to changes in transcription. The level of MUP mRNA was strongly affected by added hormones. The mRNA level at 5 days was increased by added insulin, dexamethasone, growth hormone, and thyroxine. In the presence of these three hormones, the decay in the transcription rate of the MUP genes was reduced about 10-fold. We conclude that hepatocytes plated under these nongrowing conditions can provide insights into the hormonal responsiveness of tissue-specific genes.
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Affiliation(s)
- T Spiegelberg
- Department of Genetics, University of Edinburgh, Scotland
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23
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Abstract
Primary cultures of hepatocytes isolated by collagenase perfusion of adult rats were transformed by infection with adenovirus type 5 or transfection with adenovirus DNA. Total virion DNA or recombinant plasmid DNA containing the adenovirus E1A and E1B genes transformed hepatocytes at comparable frequencies. No foci of replicating hepatocytes were detected after transfection with a plasmid containing the E1A gene alone. The frequency of transformation by the adenovirus E1A and E1B genes was dependent on the composition of the culture medium. Transformation occurred at a low frequency when the transfected hepatocytes were maintained in a chemically defined medium (CDM), but the frequency was enhanced 8- to 10-fold when the cells were maintained in (i) serum-supplemented medium or (ii) CDM supplemented with epidermal growth factor. Cell lines derived from the adenovirus-transformed colonies of hepatocytes expressed adenovirus E1A and E1B RNAs. When hepatocytes were maintained in CDM supplemented with dimethyl sulfoxide and transfected with plasmids containing the E1A and E1B genes, it was possible to derive cell lines that retained the ability to express several liver-specific genes, including albumin, transferrin, hemopexin, and the third component of complement. The amount of albumin secreted per cell varied from 1 to 5 pg per cell per 24 h, and in one cell line it was below detectable levels by passage 9. Adenovirus-transformed hepatocytes were not tumorigenic when inoculated subcutaneously into neonatal syngeneic rats. We conclude that the adenovirus E1A and E1B genes are capable of transforming adult rat hepatocytes, a differentiated epithelial cell type.
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Affiliation(s)
- C D Woodworth
- Department of Microbiology, College of Medicine, Pennsylvania State University, Hershey 17033
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