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Pascale RM, Simile MM, Peitta G, Seddaiu MA, Feo F, Calvisi DF. Experimental Models to Define the Genetic Predisposition to Liver Cancer. Cancers (Basel) 2019; 11:cancers11101450. [PMID: 31569678 PMCID: PMC6826893 DOI: 10.3390/cancers11101450] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/24/2019] [Accepted: 09/23/2019] [Indexed: 12/14/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is a frequent human cancer and the most frequent liver tumor. The study of genetic mechanisms of the inherited predisposition to HCC, implicating gene-gene and gene-environment interaction, led to the discovery of multiple gene loci regulating the growth and multiplicity of liver preneoplastic and neoplastic lesions, thus uncovering the action of multiple genes and epistatic interactions in the regulation of the individual susceptibility to HCC. The comparative evaluation of the molecular pathways involved in HCC development in mouse and rat strains differently predisposed to HCC indicates that the genes responsible for HCC susceptibility control the amplification and/or overexpression of c-Myc, the expression of cell cycle regulatory genes, and the activity of Ras/Erk, AKT/mTOR, and of the pro-apoptotic Rassf1A/Nore1A and Dab2IP/Ask1 pathways, the methionine cycle, and DNA repair pathways in mice and rats. Comparative functional genetic studies, in rats and mice differently susceptible to HCC, showed that preneoplastic and neoplastic lesions of resistant mouse and rat strains cluster with human HCC with better prognosis, while the lesions of susceptible mouse and rats cluster with HCC with poorer prognosis, confirming the validity of the studies on the influence of the genetic predisposition to hepatocarinogenesis on HCC prognosis in mouse and rat models. Recently, the hydrodynamic gene transfection in mice provided new opportunities for the recognition of genes implicated in the molecular mechanisms involved in HCC pathogenesis and prognosis. This method appears to be highly promising to further study the genetic background of the predisposition to this cancer.
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Affiliation(s)
- Rosa M Pascale
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Maria M Simile
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Graziella Peitta
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Maria A Seddaiu
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Francesco Feo
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Diego F Calvisi
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
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Abstract
Inbred mice are the most popular animals used for in vivo liver research. These mice are genetically defined, readily available, less expensive to maintain than larger animals, and enjoy a broad array of commercial reagents for scientific characterization. C57BL/6 mice are the most commonly used strain. However, other strains discussed, including BALB/c, C3H, A/J, and FVB/N, may be better suited to a particular disease model or line of investigation. Understanding the phenotypes of different inbred mouse strains facilitates informed decision making during experimental design. Model systems influenced by strain-dependent phenotype include tissue regeneration, drug-induced liver injury (DILI; e.g., acetaminophen), fibrosis (e.g., carbon tetrachloride, CCl₄), Fas-induced apoptosis, cholestasis, alcohol-induced liver disease and cirrhosis, nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH), and hepatocellular carcinoma (HCC). Thoughtful consideration of the strengths and weaknesses of each inbred strain in a given model system will lead to more robust data and a clearer understanding of translational relevance to human liver disease.
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Affiliation(s)
- Arlin B. Rogers
- Department of Early Development, Alnylam Pharmaceuticals, Cambridge, MA, USA
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Feo F, Frau M, Tomasi ML, Brozzetti S, Pascale RM. Genetic and epigenetic control of molecular alterations in hepatocellular carcinoma. Exp Biol Med (Maywood) 2009; 234:726-36. [PMID: 19429855 DOI: 10.3181/0901-mr-40] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Comparative analysis of hepatocellular carcinoma (HCC) in rat strains that are either susceptible or resistant to the induction of HCC has allowed the mapping of genes responsible for inherited predisposition to HCC. These studies show that the activity of several low penetrance genes and a predominant susceptibility gene regulate the development of hepatocarcinogenesis in rodents. These studies shed light on the epidemiology of human HCC. The identified genes regulate resistance to hepatocarcinogenesis by affecting the capacity of the initiated cells to grow autonomously and to progress to HCC. Analysis of the molecular alterations showed highest iNos cross-talk with IKK/NF-kB and RAS/ERK pathways in most aggressive liver lesions represented by HCC in the susceptible F344 rats. Unrestrained extracellular signal-regulated kinase (Erk) activity linked to proteasomal degradation of dual-specificity phosphatase 1 (Dusp1), a specific ERK inhibitor, by the CKS1-SKP2 ubiquitin ligase complex was highest in more aggressive HCC of genetically susceptible rats. Furthermore, deregulation of G1 and S phases of the cell cycle occurs in HCC of susceptible F344 rats, leading to pRb hyperphosphorylation and elevated DNA synthesis, whereas a block to G1-S transition is present in the HCC of resistant BN rats. Importantly, similar alterations in the signaling pathways that regulate cell cycle progression were found in human HCC with poorer prognosis (as defend by patients' survival length), whereas human HCC with better prognosis had molecular characteristics similar to the lesions in the HCC of resistant rat strains. This review discusses the role of molecular alterations involved in the acquisition of resistance or susceptibility to HCC and the importance of genetically susceptible and resistant rat models for the identification of prognostic markers, and chemopreventive or therapeutic targets for the biological network therapy of human disease.
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Affiliation(s)
- Francesco Feo
- Department of Biomedical Sciences, Division of Experimental Pathology and Oncology, University of Sassari, 07100 Sassari, Italy.
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Feo F, Frau M, Pascale RM. Interaction of major genes predisposing to hepatocellular carcinoma with genes encoding signal transduction pathways influences tumor phenotype and prognosis. World J Gastroenterol 2008; 14:6601-15. [PMID: 19034960 PMCID: PMC2773299 DOI: 10.3748/wjg.14.6601] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Studies on rodents and humans demonstrate an inherited predisposition to hepatocellular carcinoma (HCC). Analysis of the molecular alterations involved in the acquisition of a phenotype resistant or susceptible to hepatocarcinogenesis showed a deregulation of G1 and S phases in HCC of genetically susceptible F344 rats and a G1-S block in lesions of resistant Brown norway (BN) rats. Unrestrained extracellular signal-regulated kinase (ERK) activity linked to proteasomal degradation of dual-specificity phosphatase 1 (DUSP1), a specific ERK inhibitor, by the CKS1-SKP2 ubiquitin ligase complex occurs in more aggressive HCC of F344 rats and humans. This mechanism is less active in HCC of BN rats and human HCC with better prognosis. Upregulation of iNos cross-talk with IKK/NF-κB and RAS/ERK pathways occurs in rodent liver lesions at higher levels in the most aggressive models represented by HCC of F344 rats and c-Myc-TGF-α transgenic mice. iNOS, IKK/NF-κB, and RAS/ERK upregulation is highest in human HCC with a poorer prognosis and positively correlates with tumor proliferation, genomic instability and microvascularization, and negatively with apoptosis. Thus, cell cycle regulation and the activity of signal transduction pathways seem to be modulated by HCC modifier genes, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC.
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Waalkes MP, Liu J, Diwan BA. Transplacental arsenic carcinogenesis in mice. Toxicol Appl Pharmacol 2007; 222:271-80. [PMID: 17306315 PMCID: PMC1995036 DOI: 10.1016/j.taap.2006.12.034] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 12/01/2006] [Accepted: 12/11/2006] [Indexed: 01/12/2023]
Abstract
Our work has focused on the carcinogenic effects of in utero arsenic exposure in mice. Our data show that a short period of maternal exposure to inorganic arsenic in the drinking water is an effective, multi-tissue carcinogen in the adult offspring. These studies have been reproduced in three temporally separate studies using two different mouse strains. In these studies pregnant mice were treated with drinking water containing sodium arsenite at up to 85 ppm arsenic from days 8 to 18 of gestation, and the offspring were observed for up to 2 years. The doses used in all these studies were well tolerated by both the dam and offspring. In C3H mice, two separate studies show male offspring exposed to arsenic in utero developed liver carcinoma and adrenal cortical adenoma in a dose-related fashion during adulthood. Prenatally exposed female C3H offspring show dose-related increases in ovarian tumors and lung carcinoma and in proliferative lesions (tumors plus preneoplastic hyperplasia) of the uterus and oviduct. In addition, prenatal arsenic plus postnatal exposure to the tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate (TPA) in C3H mice produces excess lung tumors in both sexes and liver tumors in females. Male CD1 mice treated with arsenic in utero develop tumors of the liver and adrenal and renal hyperplasia while females develop tumors of urogenital system, ovary, uterus and adrenal and hyperplasia of the oviduct. Additional postnatal treatment with diethylstilbestrol or tamoxifen after prenatal arsenic in CD1 mice induces urinary bladder transitional cell proliferative lesions, including carcinoma and papilloma, and enhances the carcinogenic response in the liver of both sexes. Overall this model has provided convincing evidence that arsenic is a transplacental carcinogen in mice with the ability to target tissues of potential human relevance, such as the urinary bladder, lung and liver. Transplacental carcinogenesis clearly occurs with other agents in humans and investigating a potential transplacental component of the human carcinogenic response to arsenic should be a research priority.
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Affiliation(s)
- Michael P Waalkes
- Inorganic Carcinogenesis Section, Laboratory of Comparative Carcinogenesis, National Cancer Institute at National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
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Feo F, De Miglio MR, Simile MM, Muroni MR, Calvisi DF, Frau M, Pascale RM. Hepatocellular carcinoma as a complex polygenic disease. Interpretive analysis of recent developments on genetic predisposition. Biochim Biophys Acta Rev Cancer 2005; 1765:126-47. [PMID: 16216419 DOI: 10.1016/j.bbcan.2005.08.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Revised: 08/25/2005] [Accepted: 08/26/2005] [Indexed: 01/11/2023]
Abstract
The different frequency of hepatocellular carcinoma (HCC) in humans at risk suggests a polygenic predisposition. However, detection of genetic variants is difficult in genetically heterogeneous human population. Studies on mouse and rat models identified 7 hepatocarcinogenesis susceptibility (Hcs) and 2 resistance (Hcr) loci in mice, and 7 Hcs and 9 Hcr loci in rats, controlling multiplicity and size of neoplastic liver lesions. Six liver neoplastic nodule remodeling (Lnnr) loci control number and volume of re-differentiating lesions in rat. A Hcs locus, with high phenotypic effects, and various epistatic gene-gene interactions were identified in rats, suggesting a genetic model of predisposition to hepatocarcinogenesis with different subset of low-penetrance genes, at play in different subsets of population, and a major locus. This model is in keeping with human HCC epidemiology. Several putative modifier genes in rodents, deregulated in HCC, are located in chromosomal segments syntenic to sites of chromosomal aberrations in humans, suggesting possible location of predisposing loci. Resistance to HCC is associated with lower genomic instability and downregulation of cell cycle key genes in preneoplastic and neoplastic lesions. p16(INK4A) upregulation occurs in susceptible and resistant rat lesions. p16(INK4A)-induced growth restraint was circumvented by Hsp90/Cdc37 chaperons and E2f4 nuclear export by Crm1 in susceptible, but not in resistant rats and human HCCs with better prognosis. Thus, protective mechanisms seem to be modulated by HCC modifiers, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC.
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Affiliation(s)
- F Feo
- Department of Biomedical Sciences, Division of Experimental Pathology and Oncology, University of Sassari, Via P. Manzella 4, 07100 Sasssari, Italy.
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Bilger A, Bennett LM, Carabeo RA, Chiaverotti TA, Dvorak C, Liss KM, Schadewald SA, Pitot HC, Drinkwater NR. A potent modifier of liver cancer risk on distal mouse chromosome 1: linkage analysis and characterization of congenic lines. Genetics 2005; 167:859-66. [PMID: 15238534 PMCID: PMC1470923 DOI: 10.1534/genetics.103.024521] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The C3H/HeJ (C3H) and CBA/J (CBA) mouse strains are classical mouse models of cancer susceptibility, exhibiting high risks for both spontaneous and chemically induced liver cancer. By analysis of backcrosses and intercrosses between C3H or CBA and resistant B6 mice, we have mapped a potent modifier of hepatocellular carcinoma development to distal chromosome 1, linked to the marker D1Mit33 with combined LOD(W) scores of approximately 5.9 (C3H) and 6.5 (CBA). We previously identified this region as one of two that modify susceptibility in the more distantly related C57BR/cdJ (BR) strain. Congenic B6.C3H(D1Mit5-D1Mit17) and B6.BR(D1Mit5-D1Mit17) mice developed significantly more liver tumors than B6 mice did (6- to 13-fold, P < 10(-11), in males; 3- to 4-fold, P < 10(-3), in females). Thus, distal chromosome 1 carries one or more genes that are sufficient to confer susceptibility to liver cancer.
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Affiliation(s)
- Andrea Bilger
- McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, Madison, Wisconsin 53706, USA
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Maronpot RR, Flake G, Huff J. Relevance of animal carcinogenesis findings to human cancer predictions and prevention. Toxicol Pathol 2004; 32 Suppl 1:40-8. [PMID: 15209402 DOI: 10.1080/01926230490425003] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Use of laboratory animals to identify carcinogenic potential of chemicals, mixtures, and other agents has a modern history of greater than 40 years from which much useful scientific and public health information can be derived. While laboratory animals differ from humans in some respects that may affect responses to hazardous exposures, use of such models is based on experimental evidence indicating that there are more genetic, genomic, physiological, biochemical, and metabolic similarities than differences among mammalian species. Issues of concordance of responses between rodent species and between rodents and humans as well as repeatability and site-specificity are important considerations in evaluating laboratory animal carcinogenicity results. Variables in experimental design such as animal strain, diet, route of exposure, and study, duration as well as single-site versus multisite carcinogenic responses all influence interpretation and intelligent use of study data. Similarities and differences in site-specific laboratory animal and corresponding human cancers should also be considered in study evaluation. Recent attempts to explore genetically engineered mice and to humanize the mouse for more relevant identification of carcinogen hazard identification have yielded mixed results. In the end we are confronted by the realization that virtually all animal cancer models are useful but imperfect surrogates for humans. Assuming the percentage of chemicals currently in commerce that are estimated to be potent animal or human carcinogens is quite low, the task of identifying agents with significant carcinogenic potential is daunting and important. The biological conundrum of scientific debate regarding the relevance of carcinogenicity studies in laboratory animals is likely to continue. Nonetheless public health considerations must take precedence when deciding human safety issues.
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Affiliation(s)
- R R Maronpot
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
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Grizzle WE, Mountz JD, Yang PA, Xu X, Sun S, Van Zant GE, Williams RW, Hsu HC, Zhang HG. BXD recombinant inbred mice represent a novel T cell-mediated immune response tumor model. Int J Cancer 2002; 101:270-9. [PMID: 12209979 DOI: 10.1002/ijc.10606] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
To develop a better animal model for studying the effects of the host environment in neoplasia, we injected various genetically well-characterized H-2(d) RI strains of BXD mice with syngeneic breast cancer cells (TS/A) and monitored the growth of tumors over time. There was a marked difference in the growth of the implanted breast cancer cells among the 14 BXD RI strains, with 4 patterns of tumor development being observed: in type I, the implanted tumor cells grew rapidly in the first 2 weeks, necrosis of the tumors was observed and metastases to the intestinal lymph nodes and pancreas was observed, causing death; in type II, the implanted tumor cells grew slowly and attained a size after day 50 that required killing the animal, with tumor necrosis being rare and metastases absent; in type III, the implanted tumor cells grew initially but underwent a slow decline after 4 weeks; and in type IV, the implanted tumor cells failed to develop. Apoptosis of the implanted tumor cells was responsible for the regression of tumor nodules. The T-cell immune response minimized tumor development in types III and IV since T-cell depletion of the BXD RI mice resulted in aggressively growing tumors in these strains.
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Affiliation(s)
- William E Grizzle
- Department of Pathology, University of Alabama at Birmingham, AL 35294-0007, USA
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10
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Angel JM, Richie ER. Tlag2, anN-methyl-N-nitrosourea susceptibility locus, maps to mouse chromosome 4. Mol Carcinog 2002. [DOI: 10.1002/mc.10026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Johnson FM. How many food additives are rodent carcinogens? ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2002; 39:69-80. [PMID: 11813298 DOI: 10.1002/em.10037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
One generally assumes that chemical agents added to foods are reasonably free of risks to human health, and practically everyone consumes some additives in his or her food daily throughout life. In the United States, the 1958 Food Additives Amendment to the Federal Food, Drug and Cosmetic Act of 1938 requires food manufacturers to demonstrate the safety of food additives to the Food and Drug Administration (FDA). The Amendment contains a provision that prohibits approval of an additive if it is found to cause cancer in humans or animals. In the present study, data from the National Toxicology Program rodent bioassay (NTPRB) were used to identify a sample of approximately 50 rodent-tested additives and other chemicals added to food that had been evaluated independently of the FDA/food industry. Surprisingly, the sample shows more than 40% of these food chemicals to be carcinogenic in one or more rodent groups. If this percentage is extrapolated to all substances added to food in the United States, it would imply that more than 1000 of such substances are potential rodent carcinogens. The NTP and FDA test guidelines use similar, though not necessarily identical, rodent test procedures, including near lifetime exposures to the maximum tolerated dose. The FDA specifies that test chemicals should be administered by the oral route. However, the oral route includes three methods of delivering chemicals, that is, mixed in the food or water or delivered by stomach tube (gavage). The NTP data show only 1 of 18 food chemicals mixed in the food are rodent carcinogens, but 16 of 23 gavage-administered food chemicals are carcinogenic to rodents. The distribution suggests that among orally delivered chemicals, those administered in the feed will more likely prove to be noncarcinogens than chemicals given by gavage. The rodent data also reveal that effects may vary according to dose and genotype, as well as by route of administration, to further complicate extrapolation to humans. Human experience with known carcinogens such as tobacco, asbestos, and benzidine convinces us that environmental carcinogens constitute a real threat to human health, although predicting human carcinogens from rodent tests involves a number of uncertainties. These uncertainties do not mean that we should simply ignore the presence of carcinogens. Rather, in the interests of public safety, a serious effort should be made to resolve the questions surrounding the presence of chemicals identified as rodent carcinogens in our food. Environ. Mol. Mutagen. 39:69-80, 2002 Published 2002 Wiley-Liss, Inc.
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Affiliation(s)
- F M Johnson
- Toxicology Operations Branch, Environmental Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
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Angel JM, Caballero M, DiGiovanni J. Confirmation of the mapping of a 12-O-tetradecanoylphorbol-13-acetate promotion susceptibility locus, Psl1, to distal mouse chromosome 9. Mol Carcinog 2001; 32:169-75. [PMID: 11746828 DOI: 10.1002/mc.10010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Susceptibility to two-stage skin carcinogenesis in the mouse is affected by several genes. In addition, studies suggest that genes that modify the response of mice to skin tumor promotion by 12-O-tetradecanoylphorbol-13-acetate (TPA) also may influence histologic changes in the skin as the result of TPA treatment. One TPA susceptibility locus, Psl1, previously was mapped to distal chromosome 9. The mapping of this locus was confirmed by marker-based genotypic selection. Furthermore, Psl1 or a gene closely linked to Psl1 influenced epidermal hyperplasia and epidermal labeling index of mice treated with TPA.
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Affiliation(s)
- J M Angel
- The University of Texas M. D. Anderson Cancer Center, Science Park-Research Division, Smithville, Texas 78957, USA
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Qin X, Zhang S, Matsukuma S, Zarkovic M, Shimizu S, Ishikawa T, Nakatsuru Y. Protection against malignant progression of spontaneously developing liver tumors in transgenic mice expressing O(6)-methylguanine-DNA methyltransferase. Jpn J Cancer Res 2000; 91:1085-9. [PMID: 11092970 PMCID: PMC5926285 DOI: 10.1111/j.1349-7006.2000.tb00888.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
To study the effect of O(6)-methylguanine-DNA methyltransferase (MGMT) on carcinogenesis, we have previously generated MGMT transgenic mice overexpressing the bacterial MGMT gene, ada, and demonstrated that high MGMT levels in the liver suppress induction of liver tumors after treatment with an alkylating hepatocarcinogen. To examine the effects of life-long elevation of MGMT activity on mouse spontaneous liver tumor development, ada-transgenic and control non-transgenic mice were compared. We also examined mutations at codon 61 of the H-ras oncogene, reported as a hot spot in mouse liver tumors, using a direct DNA sequencing method. The results revealed no significant difference in tumor incidence or mutation spectrum, but interestingly, ada-transgenic mice were found to have fewer malignant tumors and survived longer, indicating a possible protective role of MGMT against malignant conversion.
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Affiliation(s)
- X Qin
- Department of Molecular Pathology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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Angel JM, Popova N, Lanko N, Turusov VS, DiGiovanni J. A locus that influences susceptibility to 1,2-dimethylhydrazine-induced colon tumors maps to the distal end of mouse chromosome 3. Mol Carcinog 2000. [DOI: 10.1002/(sici)1098-2744(200001)27:1<47::aid-mc7>3.0.co;2-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Affiliation(s)
- C C Martin
- Fels Institute for Cancer Research and Molecular Biology, Philadelphia, Pennsylvania, USA
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Lee GH. Genetic dissection of murine susceptibilities to liver and lung tumors based on the two-stage concept of carcinogenesis. Pathol Int 1998; 48:925-33. [PMID: 9952336 DOI: 10.1111/j.1440-1827.1998.tb03863.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Inbred mouse strains exhibit strain-specific susceptibilities to spontaneous and induced tumors, indicating that the individual risks for neoplastic development are largely under genetic control. Recent advances in linkage analysis have made it routine to chromosomally map the mouse genes responsible for the strain variations in tumor susceptibility using segregating crosses. It is also possible to characterize their biological functions using the positional information. These types of studies are still severely hampered for human cases due to the remarkable genetic heterogeneity and impossibility of experimental crosses. In this article, previous work on genetic susceptibility to mouse liver and lung tumors is reviewed in view of the classical two-stage concept of carcinogenesis. According to this central concept, the tumor susceptibility genes should affect either the first stage, 'initiation', or the second stage, 'promotion', or both. At least some genes seem to be specifically involved in initiation or promotion, in line with the fact that initiation and promotion are due, to a certain extent, to independent mechanisms. This notion should be also applicable to human carcinogenesis and may provide important clues for prevention of initiation and promotion in populations with a genetic predisposition for cancer development.
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Affiliation(s)
- G H Lee
- Department of Pathology, Asahikawa Medical College, Japan.
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17
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Yan Y, Higashi K, Yamamura K, Fukamachi Y, Abe T, Gotoh S, Sugiura T, Hirano T, Higashi T, Ichiba M. Different responses other than the formation of DNA-adducts between the livers of carcinogen-resistant rats (DRH) and carcinogen-sensitive rats (Donryu) to 3'-methyl-4-dimethylaminoazobenzene administration. Jpn J Cancer Res 1998; 89:806-13. [PMID: 9765615 PMCID: PMC5921908 DOI: 10.1111/j.1349-7006.1998.tb00632.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Carcinogen-resistant inbred DRH rats developed from the Donryu strain showed a remarkably low incidence of liver tumors when they were fed diets containing hepatocarcinogens such as 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB). In this work, we examined various characteristics of male DRH and Donryu rats during 3'-Me-DAB administration for 8 weeks. 32P-Postlabeling analysis showed that essentially similar levels of DNA-adducts were generated by the metabolites of 3'-Me-DAB in the livers of these two strains of rats at several time points. However, both GADD45 (growth arrest and DNA damage-inducible) and O6-methylguanine methyltransferase (putatively DNA damage-inducible) mRNA levels were increased significantly in Donryu rat livers, but were increased to a lesser extent in DRH rats. [3H]Thymidine incorporation into hepatic DNA began to increase around 10 to 20 days after the start of 3'-Me-DAB administration in Donryu rats probably due to DNA repair, while no significant change occurred in DRH rats under the same conditions. Furthermore, inductions of heme oxygenase (due to degradation of heme-proteins) and hepatocyte growth factor (HGF; cell death and regeneration of hepatocytes) mRNAs were greater in Donryu rat livers than those of DRH, suggesting that the former were more sensitive to cytotoxic effects of 3'-Me-DAB than the latter. Another remarkable difference observed between these two strains was the significant induction of cytochrome P-450 2E1 mRNA in Donryu rat livers; this may contribute to the generation of reactive oxygen intermediates. Finally, increases of glutathione S-transferase (P-form) and gamma-glutamyltranspeptidase mRNAs as marker enzymes of preneoplastic changes of hepatocytes were clearly seen only in Donryu rat livers at 6 to 8 weeks after the start of 3'-Me-DAB administration. These results indicate that the different susceptibility to hepatocarcinogenesis between these two strains of rats may arise from events other than the DNA adduct formation.
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Affiliation(s)
- Y Yan
- Department of Biochemistry, School of Medicine, University of Occupational and Environmental Health, Fukuoka
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Dass SB, Hammons GJ, Bucci TJ, Heflich RH, Casciano DA. Susceptibility of C57BL/6 mice to tumorigenicity induced by dimethylnitrosamine and 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine in the neonatal bioassay. Cancer Lett 1998; 124:105-10. [PMID: 9500198 DOI: 10.1016/s0304-3835(97)00462-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Male C57BL/6 neonates were treated on days 8 and 15 with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP, 6.5 or 26.2 mg/kg) or dimethylnitrosamine (DMN, 2.6 or 10.5 mg/kg). No tumors were seen in PhIP-treated animals at 15 months of age. Liver and lung tumor incidences in DMN-treated animals were 67-79 and 0-7%, respectively. In comparison with data from other strains, our results indicate that (1) neonatally-treated C57BL/6 mice are resistant to the induction of liver and lung tumors by PhIP and lung tumors by DMN and (2) the susceptibility of this strain to induced liver tumors correlates with the activity of hepatic DMN N-demethylase and PhIP N-hydroxylase in the (untreated) neonates.
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Affiliation(s)
- S B Dass
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, Jefferson, AR 72079, USA
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