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Zhou BW, Wu QQ, Mauki DH, Wang X, Zhang SR, Yin TT, Chen FL, Li C, Liu YH, Wang GD, Zhang YP. Germline gene fusions across species reveal the chromosomal instability regions and cancer susceptibility. iScience 2023; 26:108431. [PMID: 38205119 PMCID: PMC10777377 DOI: 10.1016/j.isci.2023.108431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 06/24/2023] [Accepted: 11/08/2023] [Indexed: 01/12/2024] Open
Abstract
The canine transmissible venereal tumor (CTVT) is a clonal cell-mediated cancer with a long evolutionary history and extensive karyotype rearrangements in its genome. However, little is known about its genetic similarity to human tumors. Here, using multi-omics data we identified 11 germline gene fusions (GGFs) in CTVT, which showed higher genetic susceptibility than others. Additionally, we illustrate a mechanism of a complex gene fusion of three gene segments (HSD17B4-DMXL1-TNFAIP8) that we refer to "greedy fusion". Our findings also provided evidence that expressions of GGFs are downregulated during the tumor regressive phase, which is associated with DNA methylation level. This study presents a comprehensive landscape of gene fusions (GFs) in CTVT, which offers a valuable genetic resource for exploring potential genetic mechanisms underlying the development of cancers in both dogs and humans.
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Affiliation(s)
- Bo-Wen Zhou
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Qing-Qin Wu
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, Yunnan 650500, China
| | - David H. Mauki
- Institute of Neurological Disease, National-Local Joint Engineering Research Center of Translational Medicine, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Xuan Wang
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Shu-Run Zhang
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Ting-Ting Yin
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Fang-Liang Chen
- Kunming Police Dog Base of the Ministry of Public Security, Kunming, Yunnan 650204, China
| | - Chao Li
- State Key Laboratory for Conservation and Utilization of Bio-Resource, Yunnan University, Kunming, Yunnan 650500, China
| | - Yan-Hu Liu
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Guo-Dong Wang
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Ya-Ping Zhang
- State Key Laboratory of Genetic Resources and Evolution & Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
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Faro TAS, de Oliveira EHC. Canine transmissible venereal tumor - From general to molecular characteristics: A review. Anim Genet 2023; 54:82-89. [PMID: 36259378 DOI: 10.1111/age.13260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/07/2022] [Accepted: 08/23/2022] [Indexed: 01/07/2023]
Abstract
Cancer is a group of complex diseases resulting from the accumulation of genetic and epigenetic changes affecting control and activity of several genes, especially those involved in cell differentiation and growth processes, leading to an abnormal proliferation. When the disease reaches an advanced stage, cancer can lead to metastasis in other organs. Interestingly, recent studies have shown that some types of cancer spread not only through the body, but also can be transmitted among individuals. Therefore, these cancers are known as transmissible tumors. Among the three types of transmissible tumors that occur in nature, the canine transmissible venereal tumor (CTVT) is known as the oldest cancer in the world, since it was originated from a single individual 11 000 years ago. The disease has a worldwide distribution, and its occurrence has been documented since 1810. The CTVT presents three types of cytomorphological classification: lymphocytoid type, mixed type, and plasmacytoid type, the latter being chemoresistant due to overexpression of the ABCB1 gene, and consequently increase of the P-glycoprotein. More knowledge about the epidemiology and evolution of CTVT may help to elucidate the pathway and form of the global spread of the disease.
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Affiliation(s)
- Thamirys A S Faro
- Programa de Pós Graduação em Genética e Biologia Molecular, Universidade Federal do Pará, Belém, Pará, Brazil
- Laboratório de Citogenômica e Mutagênese Ambiental, SEAMB, Instituto Evandro Chagas Ananindeua, Belém, Pará, Brazil
| | - Edivaldo H C de Oliveira
- Programa de Pós Graduação em Genética e Biologia Molecular, Universidade Federal do Pará, Belém, Pará, Brazil
- Laboratório de Citogenômica e Mutagênese Ambiental, SEAMB, Instituto Evandro Chagas Ananindeua, Belém, Pará, Brazil
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Setthawongsin C, Techangamsuwan S, Rungsipipat A. Canine Transmissible Venereal Tumor: An Infectious Neoplasia in Dogs. Vet Med Sci 2022. [DOI: 10.5772/intechopen.106150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Canine transmissible venereal tumor is the oldest cancer in dogs and is transplanted via viable cancer cells. This cancer has a specific host, easy transmission, noticeable gross lesions, a predictable growth pattern, an immunologic relative host response, unique molecular characteristics, and is responsive to chemotherapeutic treatment. These points make researchers and practitioners interested in this cancer. Genital cases are noticeable and therefore easier to diagnose and treat than extragenital cases. By contrasting the anatomical features of the two types of cases, we highlight the uniqueness of canine transmissible venereal tumors and discuss the diagnosis, treatment, and prevention of this ancient cancer.
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Between the Devil and the Deep Blue Sea: Non-Coding RNAs Associated with Transmissible Cancers in Tasmanian Devil, Domestic Dog and Bivalves. Noncoding RNA 2021; 7:ncrna7040072. [PMID: 34842768 PMCID: PMC8628904 DOI: 10.3390/ncrna7040072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/05/2021] [Accepted: 11/09/2021] [Indexed: 12/20/2022] Open
Abstract
Currently there are nine known examples of transmissible cancers in nature. They have been observed in domestic dog, Tasmanian devil, and six bivalve species. These tumours can overcome host immune defences and spread to other members of the same species. Non-coding RNAs (ncRNAs) are known to play roles in tumorigenesis and immune system evasion. Despite their potential importance in transmissible cancers, there have been no studies on ncRNA function in this context to date. Here, we present possible applications of the CRISPR/Cas system to study the RNA biology of transmissible cancers. Specifically, we explore how ncRNAs may play a role in the immortality and immune evasion ability of these tumours.
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Evaluation of a Canine Transmissible Venereal Tumour Cell Line with Tumour Immunity Capacity but Without Tumorigenic Property. J Vet Res 2019; 63:225-233. [PMID: 31276062 PMCID: PMC6598177 DOI: 10.2478/jvetres-2019-0024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 03/19/2019] [Indexed: 11/20/2022] Open
Abstract
Introduction Canine transmissible venereal tumour (CTVT) is a sexually transmitted tumour affecting dogs worldwide, imposing a financial burden on dog owners. A stable culture cell line in continuous passages for >18 months has only been achieved once. The present study investigated a stable CTVT cell line isolated from a bitch and its potential as a vaccine. Material and Methods A biopsy from a 2-year-old mongrel bitch with CTVT was obtained for histopathological confirmation and isolation of tumour cells. The isolated cells were cultured to passage 55 and characterised by flow cytometry, with karyotyping by GTG-banding and by PCR detection of myc S-2 and LINE AS1. The isolated CTVT cell line was also used as a preventive vaccine in a canine model. Results Histopathological analysis of the isolated tumour cells revealed typical CTVT characteristics. Constant proliferation and stable morphological characteristics were observed during culture. Phenotypic analysis determined the expression of HLA-DR+, CD5.1+, CD14+, CD45+, CD83+, CD163+, and Ly-6G-Ly-6C+. GTG-banding revealed a mean of 57 chromosomes in the karyotype with several complex chromosomal rearrangements. LINE-c-myc insertion in the isolated CTVT cell line at 550 bp was not detected. However, a 340-bp band was amplified. Isolated CTVT cell line inoculation at a concentration of 1×108 did not induce tumour growth in bitches, nor did a challenge with primary CTVT cells. Conclusion The present study successfully identified and isolated a stable CTVT cell line that may be useful in CTVT prevention.
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Vural SA, Haziroglu R, Vural MR, Polat IM, Tunc AS. Detection of progressive and regressive phase and LINE-1 retrotransposon in transfected dogs with transmissible venereal tumor during chemotherapy. J Vet Sci 2018; 19:620-626. [PMID: 30041285 PMCID: PMC6167336 DOI: 10.4142/jvs.2018.19.5.620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 05/21/2018] [Accepted: 06/25/2018] [Indexed: 11/20/2022] Open
Abstract
Canine transmissible venereal tumor (CTVT) is a tumor that commonly occurs in genital and extragenital sites of both genders. Long interspersed nuclear elements (LINE-1) retrotransposon has a pivotal role in allogenic transfection among uncontrolled dog populations. This study aimed to perform pathomorphological, immunohistochemical, and in situ polymerase chain reaction (PCR) evaluation of CTVT (n = 18) in transfected dogs during chemotherapy. Immunohistochemically, tumor phases were investigated by using specific markers (CD3, CD4, CD8, CD79, and transforming growth factor beta [TGF-β]), and investigated an amplified specific sequence of TVT LINE-1 retrotransposon by in situ PCR. Polyhedral-shaped neoplastic cells that had large, round, hypo/hyperchromatic nuclei and eosinophilic cytoplasm were detected. All marker results were positive, especially in the early weeks of recovery. CD4 and TGF-β markers were conspicuously positive at the initial stage. In situ PCR LINE-1 sequence was initially positive in only four cases. It is believed that the CD and TGF-β markers provide phase identification at tumor initiation and during chemotherapy. It is thought that presence of T and B lymphocytes, which have roles in cellular and humoral immunity, is needed so that regression of the tumor is possible.
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Affiliation(s)
- Sevil Atalay Vural
- Departments of Pathology Faculty of Veterinary Medicine, Ankara University, 06110 Ankara, Turkey
| | - Rifki Haziroglu
- Departments of Pathology Faculty of Veterinary Medicine, Ankara University, 06110 Ankara, Turkey
| | - Mehmet R Vural
- Departments of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Ankara University, 06110 Ankara, Turkey
| | - Ibrahim M Polat
- Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Kirikkale University, 71450 Kirikkale, Turkey
| | - Arda S Tunc
- Departments of Pathology Faculty of Veterinary Medicine, Ankara University, 06110 Ankara, Turkey
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Ojeda J, Mieres M, Soto F, Arnes V, Paredes E, Navarrete M. Computer tomographic imaging in 4 dogs with primary nasal canine transmissible venereal tumor and differing cellular phenotype. J Vet Intern Med 2018; 32:1172-1177. [PMID: 29604101 PMCID: PMC5980456 DOI: 10.1111/jvim.15125] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/09/2018] [Accepted: 03/01/2018] [Indexed: 12/31/2022] Open
Abstract
Primary nasal canine transmissible venereal tumor (CTVT) without genital affection is uncommon. The aim of this report was to describe the primary nasal CTVT findings and CT staging in 4 dogs with different cytological phenotypes. Three male dogs and 1 bitch were evaluated for their chronic histories of sneezing, snoring, mucopurulent nasal discharge and nasal deformation. Cytological examination of nasal secretions suggested CTVT, confirmed by histopathological examination and LINE‐1/c‐myc. Males had the plasmacytoid phenotype of CTVT, and the bitch had the lymphocytoid phenotype. CTVT were staged based on the CT findings using modified Adams staging system. The bitch was classified as stage 1, 2 males were classified as stage 3 and 1 male as stage 4. All dogs had a complete tumoral remission after chemotherapy. Plasmacytoid phenotype was identified in cases with most important damage of the nasal cavity. However, the cytological type did not affect the response to chemotherapy.
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Affiliation(s)
- Javier Ojeda
- Veterinary Clinical Science, Universidad Austral de Chile, Valdivia, Chile
| | - Marcelo Mieres
- Veterinary Clinical Science, Universidad Austral de Chile, Valdivia, Chile
| | - Francisco Soto
- Veterinary Clinical Science, Universidad Austral de Chile, Valdivia, Chile
| | - Verónica Arnes
- Veterinary Clinical Science, Universidad Austral de Chile, Valdivia, Chile
| | - Enrique Paredes
- Department of Animal Pathology, Universidad Austral de Chile, Valdivia, Chile
| | - María Navarrete
- Department of Animal Pathology, Universidad Austral de Chile, Valdivia, Chile
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8
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Bautista-Gómez L, Martínez-Castañeda S. Identification of mitochondrial DNA transfer in canine transmissible venereal tumours obtained from dogs in Mexico. Mitochondrial DNA A DNA Mapp Seq Anal 2016; 28:645-649. [PMID: 27159723 DOI: 10.3109/24701394.2016.1166220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Canine transmissible venereal tumour (CTVT) has been transmitted by cell transplantation from dog to dog, for over 10 000 years. Although initial studies report a single genetic origin for CTVT, recent samples from around the world reveal high genetic diversity. An elevated number of polymorphisms have been determined in mitochondrial DNA (mtDNA) of CTVT. The recent discovery of mtDNA transference from the host into tumoural cells could be a novel source of genetic diversity in CTVT. The aim of this study was to determine the presence of host mtDNA in samples of CTVT in Mexican dogs. Genotyping of 49 samples of CTVT and 49 samples of blood cells pertaining to affected dogs was performed by direct sequencing from the mtDNA D-loop region. Exogenous mtDNA was observed in 6% of the analysed tumours. This is the first investigation reporting the prevalence of exogenous mtDNA in CTVT in the Mexican dog population.
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Affiliation(s)
- Linda Bautista-Gómez
- a Universidad Autónoma del Estado de México, Centro Universitario Amecameca, Carretera Amecameca-Ayapango , Amecameca , Estado de México , México
| | - Simón Martínez-Castañeda
- b Centro de Investigación y Estudios Avanzados en Salud Animal, Facultad de Medicina Veterinaria y Zootecnia , Universidad Autónoma del Estado de México, Carretera de Cuota Toluca-Atlacomulco , Toluca , Estado de México , México
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9
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Castro KF, Strakova A, Tinucci-Costa M, Murchison EP. Evaluation of a genetic assay for canine transmissible venereal tumour diagnosis in Brazil. Vet Comp Oncol 2016; 15:615-618. [PMID: 27135875 DOI: 10.1111/vco.12205] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 10/10/2015] [Accepted: 11/29/2015] [Indexed: 01/20/2023]
Abstract
The canine transmissible venereal tumour (CTVT) is a transmissible cancer that is spread between dogs by the allogeneic transfer of living cancer cells. The infectious agents in CTVT are the living cancer cells themselves, which are transmitted between dogs during coitus. CTVT first arose several thousand years ago and the disease has a global distribution and is frequently observed in dogs from Brazil. We evaluated the utility of a LINE-MYC quantitative polymerase chain reaction for diagnosis of CTVT cases in Brazil. Our analysis indicated that the LINE-MYC rearrangement was detectable in all CTVT samples but not in their corresponding hosts. This genetic assay proves to be a useful tool for providing a definitive molecular diagnosis of CTVT, which presents with varying degrees of aggressiveness and invasiveness in different host dogs and can therefore be a diagnostic challenge in some specific cases.
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Affiliation(s)
- K F Castro
- Department of Veterinary Medicine, São Paulo State University, São Paulo/Jaboticabal, Brazil
| | - A Strakova
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - M Tinucci-Costa
- Department of Veterinary Medicine, São Paulo State University, São Paulo/Jaboticabal, Brazil
| | - E P Murchison
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
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10
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Setthawongsin C, Techangamsuwan S, Tangkawattana S, Rungsipipat A. Cell-based polymerase chain reaction for canine transmissible venereal tumor (CTVT) diagnosis. J Vet Med Sci 2016; 78:1167-73. [PMID: 27075116 PMCID: PMC4976273 DOI: 10.1292/jvms.15-0710] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Canine transmissible venereal tumor (CTVT) is the only naturally contagious tumor that is
transmitted during coitus or social behaviors. Based on the tumor’s location, the
diagnosis of genital TVT (GTVT) is comparably easier than those in the extragenital area
(ETVT) that are more easily incorrectly diagnosed. Fortunately, CTVT cells contain a
specific long interspersed nuclear elements (LINE), inserted upstream of the
myc gene, allowing a diagnostic polymerase chain reaction (PCR) based
detection assay. The objectives of this study were aimed to improve the diagnostic
accuracy by applying the diagnostic LINE1-c-myc PCR assay and fine needle
aspiration (FNA) collection in direct comparison with standard cytological and
histopathological analyses. Seventy-four dogs, comprised of 41 and 31 dogs with tumor
masses at their external genitalia and extragenital areas (e.g. skin and nasal cavity),
respectively, were included in this study. The signalment of these 65 dogs and clinical
history of 20 client-owned dogs were collected. Samples were taken by biopsy for both
histopathological examination and FNA for cytological examination and diagnostic PCR. The
PCR products from 10 apparently CTVT samples were purified and sequenced. Sixty-one CTVT
cases were diagnosed by cytological and histological analyses, but 65 were positive by the
PCR assay. Overall, the PCR assay improved the accuracy of diagnostic CTVT results,
especially for the more difficult ETVT tumors. Moreover, this PCR-based approach can
facilitate the decision as to discontinue chemotherapy by discrimination between residual
tumor cell masses and fibrotic tissue.
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Affiliation(s)
- Chanokchon Setthawongsin
- Companion Animal Cancer Research Unit, Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
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Ujvari B, Gatenby RA, Thomas F. The evolutionary ecology of transmissible cancers. INFECTION GENETICS AND EVOLUTION 2016; 39:293-303. [PMID: 26861618 DOI: 10.1016/j.meegid.2016.02.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/20/2022]
Abstract
Transmissible tumours, while rare, present a fascinating opportunity to examine the evolutionary dynamics of cancer as both an infectious agent and an exotic, invasive species. Only three naturally-occurring transmissible cancers have been observed so far in the wild: Tasmanian devil facial tumour diseases, canine transmissible venereal tumour, and clam leukaemia. Here, we define four conditions that are necessary and sufficient for direct passage of cancer cells between either vertebrate or invertebrate hosts. Successful transmission requires environment and behaviours that facilitate transfer of tumour cells between hosts including: tumour tissue properties that promote shedding of large numbers of malignant cells, tumour cell plasticity that permits their survival during transmission and growth in a new host, and a 'permissible' host or host tissue. This rare confluence of multiple host- and tumour cell-traits both explains the rarity of tumour cell transmission and provides novel insights into the dynamics that both promote and constrain their growth.
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Affiliation(s)
- Beata Ujvari
- Deakin University, Geelong, School of Life and Environmental Sciences, Centre for Integrative Ecology, Waurn Ponds, Vic 3216, Australia.
| | - Robert A Gatenby
- Department of Radiology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
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12
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Ostrander EA, Davis BW, Ostrander GK. Transmissible Tumors: Breaking the Cancer Paradigm. Trends Genet 2015; 32:1-15. [PMID: 26686413 DOI: 10.1016/j.tig.2015.10.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 09/11/2015] [Accepted: 10/15/2015] [Indexed: 12/23/2022]
Abstract
Transmissible tumors are those that have transcended the bounds of their incipient hosts by evolving the ability to infect another individual through direct transfer of cancer cells, thus becoming parasitic cancer clones. Coitus, biting, and scratching are transfer mechanisms for the two primary species studied, the domestic dog (Canis lupus familiaris) and the Tasmanian devil (Sarcophilus harrisii). Canine transmissible venereal tumors (CTVT) are likely thousands of years old, and have successfully travelled from host to host around the world, while the Tasmanian devil facial tumor disease (DFTD) is much younger and geographically localized. The dog tumor is not necessarily lethal, while the devil tumor has driven the population to near extinction. Transmissible tumors are uniform in that they have complex immunologic profiles, which allow them to escape immune detection by their hosts, sometimes for long periods of time. In this review, we explore how transmissible tumors in CTVT, DFTD, and as well as the soft-shell clam and Syrian hamster, can advance studies of tumor biology.
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Affiliation(s)
- Elaine A Ostrander
- National Human Genome Research Institute, National Institutes of Health, 50 South Drive, Building 50 Room 5351, Bethesda MD 20892, USA.
| | - Brian W Davis
- National Human Genome Research Institute, National Institutes of Health, 50 South Drive, Building 50 Room 5351, Bethesda MD 20892, USA
| | - Gary K Ostrander
- Department of Biomedical Science, 600W College Ave, College of Medicine, Florida State University, Tallahassee, Tallahassee, FL 32306, USA
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Bautista-Gómez LG, Martínez-Castañeda S, Córdova-Alarcón E, Vázquez-Chagoyán JC. Analysis of canine transmissible veneral tumor genotypes using the D-loop region of mitochondrial DNA. Genes Genet Syst 2012; 86:351-5. [PMID: 22362033 DOI: 10.1266/ggs.86.351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Canine transmissible venereal tumor (CTVT) is the only neoplasm that can be spread among dogs through cell transplantation. Therefore, this tumor does not originate from host cell transformation. Although CTVT has a monophyletic origin, several studies have shown the presence of genetic diversity which was probably acquired after the development of its original clone. To investigate the genetic diversity of CTVT in Mexico and its relation with CTVTs disseminated worldwide, we sequenced a fragment of mitochondrial DNA in 50 tumor samples and matched blood samples from dog hosts from Mexico. We found ten new haplotypes in tumor samples, which were all distinct from their matched host. The TVT1 haplotype was the most frequent in our samples, suggesting that it could be the origin of the others. We found that haplotypes in Mexico and other countries are distributed in two well-defined clusters. Our data also suggest a close relationship among American haplotypes (Mexico, USA, Chile and Brazil). Interestingly, these American haplotypes were also closely related to Asian haplotypes. Taking into account the estimated timing of the origin of CTVT, we propose that CTVT might have originated in Asia; consequently, haplotypes currently present in America could descend from Asiatic lineages.
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Affiliation(s)
- Linda G Bautista-Gómez
- Centro de Investigación y Estudios Avanzados en Salud Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Toluca Edo, Mexico
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14
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O'Neill ID. Concise review: transmissible animal tumors as models of the cancer stem-cell process. Stem Cells 2012; 29:1909-14. [PMID: 21956952 DOI: 10.1002/stem.751] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Tasmanian devil facial tumor disease (DFTD) and canine transmissible venereal tumor (CTVT) are highly unusual cancers capable of being transmitted between animals as an allograft. The concept that these tumors represent a cancer stem-cell process has never been formally evaluated. For each, evidence of self-renewal is found in the natural history of these tumors in the wild, tumor initiation in recipient animals, and serial transplantation studies. Additional data for stem-cell-specific genes and markers in DFTD also exist. Although both tumor types manifest as undifferentiated cancers, immunocytohistochemistry supports a histiocytic phenotype for CTVT and a neural crest origin, possibly a Schwann-cell phenotype, for DFTD. In these data, differential expression of lineage markers is seen which may suggest some capacity for differentiation toward a heterogeneous variety of cell types. It is proposed that DFTD and CTVT may represent and may serve as models of the cancer stem-cell process, but formal investigation is required to clarify this. Appreciation of any such role may act as a stimulus to ongoing research in the pathology of DFTD and CTVT, including further characterization of their origin and phenotype and possible therapeutic approaches. Additionally, they may provide valuable models for future studies of their analogous human cancers, including any putative CSC component.
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Affiliation(s)
- Iain D O'Neill
- de l'immeuble 3, Centre d'Affaires Poincaré, 3 Rue Poincaré, Nice, France.
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15
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Abstract
Cancer is generally defined as uncontrollable growth of cells caused by genetic aberrations and/or environmental factors. Yet contagious cancers also occur. The recent emergence of a contagious cancer in Tasmanian devils has reignited interest in transmissible cancers. Two naturally occurring transmissible cancers are known: devil facial tumour disease and canine transmissible venereal tumour. Both cancers evolved once and have then been transmitted from one individual to another as clonal cell lines. The dog cancer is ancient; having evolved more than 6,000 years ago, while the devil disease was first seen in 1996. In this review I will compare and contrast the two diseases focusing on the life histories of the clonal cell lines, their evolutionary trajectories and the mechanisms by which they have achieved immune tolerance. A greater understanding of these contagious cancers will provide unique insights into the role of the immune system in shaping tumour evolution and may uncover novel approaches for treating human cancer.
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Affiliation(s)
- Katherine Belov
- Faculty of Veterinary Science, University of Sydney, Sydney, Australia.
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16
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Immunopathogenic behaviors of canine transmissible venereal tumor in dogs following an immunotherapy using dendritic/tumor cell hybrid. Vet Immunol Immunopathol 2011; 139:187-99. [DOI: 10.1016/j.vetimm.2010.10.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 09/20/2010] [Accepted: 10/05/2010] [Indexed: 01/28/2023]
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17
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Belov K. The role of the Major Histocompatibility Complex in the spread of contagious cancers. Mamm Genome 2010; 22:83-90. [DOI: 10.1007/s00335-010-9294-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 10/05/2010] [Indexed: 02/08/2023]
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18
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Lopes RA, Cardoso TC, Luvizotto MCR, de Andrade AL. Occurrence and expression of p53 suppressor gene and c-Myc oncogene in dog eyelid tumors. Vet Ophthalmol 2010; 13:69-75. [DOI: 10.1111/j.1463-5224.2009.00753.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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19
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Sánchez-Servín A, Martínez S, Córdova-Alarcon E, Fajardo R. TP53 Polymorphisms allow for genetic sub-grouping of the canine transmissible venereal tumor. J Vet Sci 2010; 10:353-5. [PMID: 19934603 PMCID: PMC2807274 DOI: 10.4142/jvs.2009.10.4.353] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The canine transmissible venereal tumor (CTVT) is found mainly in dogs' sexual organs. Currently, it is widely accepted that all samples of CTVT show similar histopathological characteristics and share common genetic alterations. Despite the common genetic origin of CTVT, mutations in the P53 gene have been reported. In this study, we proposed that tumor samples can be genetically grouped using this gene. The presence of different subgroups of CTVT was determined in Mexican dogs using the TP53 gene sequence in CTVT samples. Four new polymorphisms were found and therefore, the CTVT samples were classified in five subgroups.
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Affiliation(s)
- Abel Sánchez-Servín
- Centro de Investigación y de Estudios Avanzados en Salud Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Carretera de cuota Toluca-Atlacomulco, Kilómetro 15.5 C.P. 50200, Toluca Edo, México
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20
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Abstract
Tasmanian devil facial tumor disease (DFTD) and canine transmissible venereal tumor (CTVT) are the only known naturally occurring clonally transmissible cancers. These cancers are transmitted by the physical transfer of viable tumor cells that can be transplanted across histocompatibility barriers into unrelated hosts. Despite their common etiology, DFTD and CTVT have evolved independently and have unique life histories and host adaptations. DFTD is a recently emerged aggressive facial tumor that is threatening the Tasmanian devil with extinction. CTVT is a sexually transmitted tumor of dogs that has a worldwide distribution and that probably arose thousands of years ago. By contrasting the biology, molecular genetics and immunology of these two unusual cancers, I highlight the common and unique features of clonally transmissible cancers, and discuss the implications of clonally transmissible cancers for host-pathogen evolution.
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Affiliation(s)
- E P Murchison
- Cancer Genome Project, Wellcome Trust Sanger Institute, Cambridge, UK.
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21
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Thomas R, Rebbeck C, Leroi AM, Burt A, Breen M. Extensive conservation of genomic imbalances in canine transmissible venereal tumors (CTVT) detected by microarray-based CGH analysis. Chromosome Res 2009; 17:927-34. [PMID: 19798471 DOI: 10.1007/s10577-009-9080-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 09/01/2009] [Indexed: 01/06/2023]
Abstract
Canine transmissible venereal tumor (CTVT) is an intriguing cancer that is transmitted naturally as an allograft by transplantation of viable tumor cells from affected to susceptible dogs. At least initially, the tumor is able to evade the host's immune response; thus, CTVT has potential to provide novel insights into tumor immunobiology. The nature of CTVT as a "contagious" cancer, originating from a common ancestral source of infection, has been demonstrated previously by a series of studies comparing geographically distinct tumors at the molecular level. While these studies have revealed that apparently unrelated tumors share a striking degree of karyotypic conservation, technological restraints have limited the ability to investigate the chromosome composition of CTVTs in any detail. We present characterization of a strategically selected panel of CTVT cases using microarray-based comparative genomic hybridization analysis at ~one-megabase resolution. These data show for the first time that the tumor presents with an extensive range of non-random chromosome copy number aberrations that are distributed widely throughout the dog genome. The majority of abnormalities detected were imbalances of small subchromosomal regions, often involving centromeric and telomeric sequences. All cases also showed the sex chromosome complement XO. There was remarkable conservation in the cytogenetic profiles of the tumors analyzed, with only minor variation observed between different cases. These data suggest that the CTVT genome demonstrates a vast degree of both structural and numerical reorganization that is maintained during transmission among the domestic dog population.
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Affiliation(s)
- Rachael Thomas
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC, 27606, USA
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22
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Rebbeck CA, Thomas R, Breen M, Leroi AM, Burt A. ORIGINS AND EVOLUTION OF A TRANSMISSIBLE CANCER. Evolution 2009; 63:2340-9. [DOI: 10.1111/j.1558-5646.2009.00724.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Chuang TF, Lee SC, Liao KW, Hsiao YW, Lo CH, Chiang BL, Lin XZ, Tao MH, Chu RM. Electroporation-mediated IL-12 gene therapy in a transplantable canine cancer model. Int J Cancer 2009; 125:698-707. [PMID: 19431145 DOI: 10.1002/ijc.24418] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Interleukin-12 (IL-12) is effective in treating many types of rodent tumors, but has been unsuccessful in most human clinical trials, suggesting that animal models of more clinical relevance are required for evaluating human cancer immunotherapy. Herein, we report on the effectiveness of gene therapy with plasmid encoding human IL-12 (pIL-12) through in vivo electroporation in the treatment of beagles with a canine tumor, the canine transmissible venereal tumor (CTVT). The optimal electroporation conditions for gene transfer into CTVTs were tested by luciferase activity and determined to be a voltage of 200 V and duration of 50 msec, with the number of shocks set at 10 pulses, and the use of an electrode with 2 needles. Under these conditions, intratumoral administration of as little as 0.1 mg pIL-12 followed by electroporation significantly inhibited the growth of well-established tumors and eventually led to complete tumor regression. Furthermore, local pIL-12 treatment also induced a strong systemic effect that prevented new tumor growth and cured established tumors at distant locations. Intratumoral administration of pIL-12 greatly elevated the IL-12 level in the tumor masses, but produced only a trace amount in the serum. A high level of IFN-gamma mRNA was also detected in the treated tumor masses. pIL-12 gene therapy attracted significantly more lymphocytes infiltrating the tumors, including CD4(+) and CD8(+) T cells, and the surface expression of MHC I and MHC II molecules on CTVT cells was greatly increased after pIL-12 therapy. This treatment also induced apoptosis of the tumor cells as detected by Annexin V. More importantly, delivery of pIL-12 with intratumoral electroporation did not result in any detectable toxicity in the dogs. We conclude that intratumoral electroporation of the pIL-12 gene could cause profound immunologic host responses and efficiently treat CTVT in beagle dogs. The results also indicate that CTVT is an excellent large animal cancer model for testing immunogene therapies mediated by electroporation.
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Affiliation(s)
- Tien-Fu Chuang
- Department of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, The Republic of China
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24
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Hsiao YW, Liao KW, Chung TF, Liu CH, Hsu CD, Chu RM. Interactions of host IL-6 and IFN-gamma and cancer-derived TGF-beta1 on MHC molecule expression during tumor spontaneous regression. Cancer Immunol Immunother 2008; 57:1091-104. [PMID: 18259750 PMCID: PMC11029876 DOI: 10.1007/s00262-007-0446-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Accepted: 12/18/2007] [Indexed: 12/18/2022]
Abstract
Many tumors down-regulate major histocompatibility complex (MHC) antigen expression to evade host immune surveillance. However, there are very few in vivo models to study MHC antigen expression during tumor spontaneous regression. In addition, the roles of transforming growth factor betal (TGF-beta1), interferon gamma (IFN-gamma), and interleukin (IL)-6 in modulating MHC antigen expression are ill understood. We previously reported that tumor infiltrating lymphocyte (TIL)-derived IL-6 inhibits TGF-beta1 and restores natural killing (NK) activity. Using an in vivo canine-transmissible venereal tumor (CTVT) tumor model, we presently assessed IL-6 and TGF-beta involvement associated with the MHC antigen expression that is commonly suppressed in cancers. IL-6, IFN-gamma, and TGF-beta1, closely interacted with each other and modulated MHC antigen expression. In the presence of tumor-derived TGF-beta1, host IFN-gamma from TIL was not active and, therefore, there was low expression of MHC antigen during tumor progression. TGF-beta1-neutralizing antibody restored IFN-gamma-activated MHC antigen expression on tumor cells. The addition of exogenous IL-6 that has potent anti-TGF-beta1 activity restored IFN-gamma activity and promoted MHC antigen expression. IFN-gamma and IL-6 in combination acted synergistically to enhance the expression of MHC antigen. Thus, the three cytokines, IL-6, TGF-beta1, and IFN-gamma, closely interacted to modulate the MHC antigen expression. Furthermore, transcription factors, including STAT-1, STAT-3, IRF-1, NF-kappaB, and CREB, were significantly elevated after IL-6 and IFN-gamma treatment. We conclude that the host IL-6 derived from TIL works in combination with host IFN-gamma to enhance MHC molecule expression formerly inhibited by TGF-beta1, driving the tumor toward regression. It is suggested that the treatment of cancer cells that constitutively secrete TGF-beta1 should incorporate anti-TGF-beta activity. The findings in this in vivo tumor regression model have potential applications in cancer immunotherapy.
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Affiliation(s)
- Ya-Wen Hsiao
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, ROC
| | - Kuang-Wen Liao
- Department of the Biological Science and Technology, National Chiao Tung University, Hsin-Chu, Taiwan, ROC
| | - Tien-Fu Chung
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Chen-Hsuan Liu
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Chia-Da Hsu
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Rea-Min Chu
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC
- Department of Veterinary Medicine, Animal Cancer Research Center, 1 Roosevelt Road, Section 4, Taipei, 106 Taiwan, ROC
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25
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Vázquez-Mota N, Simón-Martínez J, Córdova-Alarcon E, Lagunes L, Fajardo R. The T963C mutation of TP53 gene does not participate in the clonal origin of canine TVT. Vet Res Commun 2007; 32:187-91. [PMID: 17668284 DOI: 10.1007/s11259-007-9013-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 06/26/2007] [Indexed: 10/23/2022]
Abstract
In dogs, the canine transmissible venereal tumor (CTVT) is the only neoplasm which is not produced by neoplastic transformation of normal cells; the tumor is transmitted from the affected dog to healthy dogs by implantation of one or various clones of cancer cells. Thus, the CTVT of dogs analyzed in various countries reveals similar genetic characteristics and consequently CTVT is considered to have a clonal origin. The CTVTs obtained from dogs in Korea showed the T963C mutation on TP53 gene; this mutation was thought to be a molecular alteration which participates in the origin of the ancestral clone, CTVT. Nonetheless, this supposed mutation has not been identified in other studies which were carried out for the purpose of clarifying the clonal origin of CTVT. Thus we have considered it important to identify the role of the T963C mutation of the TP53 gene in the clonal origin of CTVT in dogs. Consequently the region which includes the mutation of the TP53 gene in twenty samples of CTVT obtained from various canine breeds was PCR amplified and afterwards its sequence of nucleotides was determined. We conclude that this mutation did not participate in the clonal origin of the tumor, but was acquired at a later stage.
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Affiliation(s)
- N Vázquez-Mota
- Centro de Investigación y de Estudios Avanzados en Salud Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Carretera de cuota Toluca-Atlacomulco, Kilómetro 15.5, C.P. 50200 Toluca Edo, Mexico
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26
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Park MS, Kim Y, Kang MS, Oh SY, Cho DY, Shin NS, Kim DY. Disseminated transmissible venereal tumor in a dog. J Vet Diagn Invest 2007; 18:130-3. [PMID: 16566273 DOI: 10.1177/104063870601800123] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Transmissible venereal tumor (TVT) is a well-documented transplantable tumor in dogs, with no breed or sex predilection and a low metastatic rate. In this report, a 2-year-old intact female Mastiff that had numerous, rapidly growing masses throughout the subcutis mainly at the dorsal body plane, the caudal half of the ventral abdomen, and around the vulva was euthanized due to poor prognosis. Neoplastic nodules similar to those seen in the subcutis were also noted in the lung, anterior mediastinum, liver, spleen, kidney, and superficial and deep lymph nodes in both abdominal and thoracic cavities. The neoplastic nodules from the subcutis as well as metastatic foci revealed similar cytologic and histologic features, which were consistent with canine TVT. By immunohistochemical staining, the neoplastic cells were positive for lysozyme and vimentin but were negative for cytokeratin, desmin, CD3, and CD79a. The diagnosis of the TVT was further supported by the identification and analysis of long interspersed nuclear elements (LINE) from paraffin-embedded tumor tissue. This case is a rare example of TVT with multiorgan metastasis. In this case, the polymerase chain reaction technique was useful in differential diagnosis of canine round cell tumors because this technique can be applied in retrospective as well as future study.
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Affiliation(s)
- Mi-Sun Park
- Department of Veterinary Pathology, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Korea
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27
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Abstract
In this issue of Cell, Murgia et al. (2006) confirm that the infectious agent of canine transmissible venereal tumor is the cancer cell itself and that the tumor is clonal in origin. Their findings have implications for understanding the relationship between genome instability and transmissible cancer and for conservation biology, canine genomics, and companion animal medicine.
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Affiliation(s)
- Bridgett M VonHoldt
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA
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28
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Murgia C, Pritchard JK, Kim SY, Fassati A, Weiss RA. Clonal origin and evolution of a transmissible cancer. Cell 2006; 126:477-87. [PMID: 16901782 PMCID: PMC2593932 DOI: 10.1016/j.cell.2006.05.051] [Citation(s) in RCA: 257] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Revised: 05/15/2006] [Accepted: 05/25/2006] [Indexed: 01/08/2023]
Abstract
The transmissible agent causing canine transmissible venereal tumor (CTVT) is thought to be the tumor cell itself. To test this hypothesis, we analyzed genetic markers including major histocompatibility (MHC) genes, microsatellites, and mitochondrial DNA (mtDNA) in naturally occurring tumors and matched blood samples. In each case, the tumor is genetically distinct from its host. Moreover, tumors collected from 40 dogs in 5 continents are derived from a single neoplastic clone that has diverged into two subclades. Phylogenetic analyses indicate that CTVT most likely originated from a wolf or an East Asian breed of dog between 200 and 2500 years ago. Although CTVT is highly aneuploid, it has a remarkably stable genotype. During progressive growth, CTVT downmodulates MHC antigen expression. Our findings have implications for understanding genome instability in cancer, natural transplantation of allografts, and the capacity of a somatic cell to evolve into a transmissible parasite.
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Affiliation(s)
- Claudio Murgia
- MRC/UCL Centre for Medical Molecular Virology, Division of Infection and Immunity, University College London, 46 Cleveland Street, London W1T 4JF, UK
| | - Jonathan K. Pritchard
- Department of Human Genetics, University of Chicago, CLSC–507, 920 East 58th Street, Chicago, IL 60637, USA
| | - Su Yeon Kim
- Department of Statistics, University of Chicago, CLSC–507, 920 East 58th Street, Chicago, IL 60637, USA
| | - Ariberto Fassati
- MRC/UCL Centre for Medical Molecular Virology, Division of Infection and Immunity, University College London, 46 Cleveland Street, London W1T 4JF, UK
| | - Robin A. Weiss
- MRC/UCL Centre for Medical Molecular Virology, Division of Infection and Immunity, University College London, 46 Cleveland Street, London W1T 4JF, UK
- Contact:
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