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Cousens C, Meehan J, Collie D, Wright S, Chang Z, Todd H, Moore J, Grant L, Daniel CR, Tennant P, Ritchie A, Nixon J, Proudfoot C, Guido S, Brown H, Gray CD, MacGillivray TJ, Clutton RE, Greenhalgh SN, Gregson R, Griffiths DJ, Spivey J, Storer N, Eckert CE, Gray M. Tracking Ovine Pulmonary Adenocarcinoma Development Using an Experimental Jaagsiekte Sheep Retrovirus Infection Model. Genes (Basel) 2024; 15:1019. [PMID: 39202379 PMCID: PMC11353984 DOI: 10.3390/genes15081019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 07/23/2024] [Accepted: 07/25/2024] [Indexed: 09/03/2024] Open
Abstract
Ovine pulmonary adenocarcinoma (OPA) is an infectious, neoplastic lung disease of sheep that causes significant animal welfare and economic issues throughout the world. Understanding OPA pathogenesis is key to developing tools to control its impact. Central to this need is the availability of model systems that can monitor and track events after Jaagsiekte sheep retrovirus (JSRV) infection. Here, we report the development of an experimentally induced OPA model intended for this purpose. Using three different viral dose groups (low, intermediate and high), localised OPA tumour development was induced by bronchoscopic JSRV instillation into the segmental bronchus of the right cardiac lung lobe. Pre-clinical OPA diagnosis and tumour progression were monitored by monthly computed tomography (CT) imaging and trans-thoracic ultrasound scanning. Post mortem examination and immunohistochemistry confirmed OPA development in 89% of the JSRV-instilled animals. All three viral doses produced a range of OPA lesion types, including microscopic disease and gross tumours; however, larger lesions were more frequently identified in the low and intermediate viral groups. Overall, 31% of JSRV-infected sheep developed localised advanced lesions. Of the sheep that developed localised advanced lesions, tumour volume doubling times (calculated using thoracic CT 3D reconstructions) were 14.8 ± 2.1 days. The ability of ultrasound to track tumour development was compared against CT; the results indicated a strong significant association between paired CT and ultrasound measurements at each time point (R2 = 0.799, p < 0.0001). We believe that the range of OPA lesion types induced by this model replicates aspects of naturally occurring disease and will improve OPA research by providing novel insights into JSRV infectivity and OPA disease progression.
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Affiliation(s)
- Chris Cousens
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - James Meehan
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - David Collie
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Steven Wright
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Ziyuan Chang
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Helen Todd
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - Jo Moore
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - Lynn Grant
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Carola R. Daniel
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Peter Tennant
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Adrian Ritchie
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - James Nixon
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Chris Proudfoot
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Stefano Guido
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Helen Brown
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Calum D. Gray
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK;
| | - Tom J. MacGillivray
- Centre for Clinical Brain Sciences, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, EH16 4SB, UK;
| | - R. Eddie Clutton
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Stephen N. Greenhalgh
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Rachael Gregson
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - David J. Griffiths
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - James Spivey
- Interventional Oncology, Johnson & Johnson Enterprise Innovation, Inc., One Johnson & Johnson Plaza, New Brunswick, NJ 08933, USA; (J.S.); (N.S.); (C.E.E.)
| | - Nicole Storer
- Interventional Oncology, Johnson & Johnson Enterprise Innovation, Inc., One Johnson & Johnson Plaza, New Brunswick, NJ 08933, USA; (J.S.); (N.S.); (C.E.E.)
| | - Chad E. Eckert
- Interventional Oncology, Johnson & Johnson Enterprise Innovation, Inc., One Johnson & Johnson Plaza, New Brunswick, NJ 08933, USA; (J.S.); (N.S.); (C.E.E.)
| | - Mark Gray
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
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Scott PR, Dagleish MP, Cousens C. Development of superficial lung lesions monitored on farm by serial ultrasonographic examination in sheep with lesions confirmed as ovine pulmonary adenocarcinoma at necropsy. Ir Vet J 2018; 71:23. [PMID: 30450192 PMCID: PMC6219085 DOI: 10.1186/s13620-018-0134-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 10/18/2018] [Indexed: 11/24/2022] Open
Abstract
Background This ultrasonographic study monitored lesions involving the lung surface suspected to be the early stages of ovine pulmonary adenocarcinoma (OPA) tumours over 4 months in commercially farmed sheep. The enlargement of these lesions defined ultrasonographically, which likely represent the development of OPA tumours, have important implications for ultrasound screening schedules in veterinary management plans attempting to eliminate OPA by test-and-cull. Results The lungs of 58 adult Scottish Blackface sheep with ultrasonographic changes at the lung surface consistent with early OPA tumours were examined two to six times over 40 to 290 days. Lesion development, represented in early video recordings by 2–3 mm lesions involving the visceral pleural and comet tails, then a decreasing length of the hyperechoic line representing the normal visceral pleura and increasing depth of the sharply-demarcated and largely uniform hypoechoic areas into the lung parenchyma, was found in 26 of the 58 sheep. The rate at which the sonographic lesions progressed varied considerably and in 10 of 17 Group 1 sheep developed quickly from an estimated depth of 2–30 mm up to 70 mm between 60 and 120 days later. These sonographic lesions were confirmed as OPA at necropsy; histological changes of concurrent bacterial infection were detected in one of these 10 Group 1 sheep. Thirty-one sheep had sonographic changes ≤30 mm consistent with very early OPA at the first examination which had reduced or were not observed at subsequent examination. Five of these 31 sheep were necropsied, 3 had small OPA lesions while 2 had no significant pathology. Conclusion Lesions involving the visceral pleura, with sonographic changes consistent with previous published findings of early OPA, developed over 40–120 days to large masses in 10 of 17 Group 1 sheep with the provisional sonographic diagnosis confirmed histologically at necropsy. While it is possible that atalectic lung could have caused some of the minor sonographic changes there was no microscopic evidence of pathologies other than OPA in nine of 10 Group 1 sheep. We conclude that some small tumours progress to large tumours within 3 months questioning the assumption that OPA is a slow growing tumour in adult sheep taking several years to cause clinical disease. The findings that a proportion of small ultrasonographic lesions are not found again at subsequent scanning illustrates the challenges of interpreting small (< 1–2 cm) lesions during rapid whole flock ultrasonographic examination and we continue to recommend re-scanning suspicious sonographic changes 2 months later. Electronic supplementary material The online version of this article (10.1186/s13620-018-0134-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- P R Scott
- Capital Veterinary Services, West Latchfields, Scotland, EH41 4JN UK
| | - M P Dagleish
- 2Moredun Research Institute, Bush Loan, Scotland, Penicuik EH26 0PZ UK
| | - C Cousens
- 2Moredun Research Institute, Bush Loan, Scotland, Penicuik EH26 0PZ UK
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Walsh SR, Stinson KJ, Menzies PI, Wootton SK. Development of an ante-mortem diagnostic test for enzootic nasal tumor virus and detection of neutralizing antibodies in host serum. J Gen Virol 2014; 95:1843-1854. [PMID: 24836673 DOI: 10.1099/vir.0.064956-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Enzootic nasal adenocarcinoma (ENA) is a contagious neoplasm of the nasal mucosa of sheep and goats and is associated with enzootic nasal tumour virus (ENTV). As ENA is a common disease in North America and there are no vaccines against ENTV-1, diagnostic tests that can identify infected animals and assist with eradication and disease surveillance efforts are greatly needed. In this study, we endeavoured to develop a novel, non-invasive diagnostic tool that could be used not only to validate clinical signs of ENA but also to detect ENTV-1 infection prior to the onset of disease signs (i.e. pre-clinical diagnosis). Cytology, serology and reverse transcription (RT)-PCR-based diagnostic methods were investigated. Although the cytology-based assay was able to detect ENTV-1 infection in some animals, it had poor sensitivity and specificity and thus was not developed further as an ante-mortem diagnostic method. Three different assays, including ELISA, Western blotting and virus neutralization, were developed to detect the presence of ENTV-1-specific antibodies in sheep serum. Whilst a surprisingly large number of sheep mounted an antibody-mediated immune response against ENTV-1, and in some cases neutralizing, correlation with disease status was poor. In contrast, RT-PCR on RNA extracted from nasal swabs reliably detected exogenous ENTV-1 sequences, did not amplify endogenous ovine betaretroviral sequences, demonstrated high concordance with immunohistochemical staining for ENTV-1 envelope protein, and had perfect sensitivity and specificity. This report describes a practical and highly specific RT-PCR technique for the detection of clinical and pre-clinical ENA that may prove beneficial in future control or eradication programmes.
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Affiliation(s)
- Scott R Walsh
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Kevin J Stinson
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Paula I Menzies
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Sarah K Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
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Walsh SR, Linnerth-Petrik NM, Laporte AN, Menzies PI, Foster RA, Wootton SK. Full-length genome sequence analysis of enzootic nasal tumor virus reveals an unusually high degree of genetic stability. Virus Res 2010; 151:74-87. [PMID: 20398709 DOI: 10.1016/j.virusres.2010.04.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 04/01/2010] [Accepted: 04/05/2010] [Indexed: 12/18/2022]
Abstract
Enzootic nasal tumor virus (ENTV) is a betaretrovirus of sheep (ENTV-1) and goats (ENTV-2) associated with neoplastic transformation of epithelial cells of the ethmoid turbinate. Confirmation of the role of ENTV in the pathogenesis of enzootic nasal adenocarcinoma (ENA) has yet to be resolved due to the lack of an infectious molecular clone and the inability to culture the virus. Very little is known about the prevalence of this disease, particularly in North America, and only one full-length sequence is available for each of ENTV-1 and ENTV-2. In order to understand the molecular evolution of ENTV-1, the full-length genome sequence of ten ENTV-1 proviruses derived from clinical samples of ENA isolated from conventionally reared sheep in Canada and the United States was determined. The North American ENTV-1 (ENTV-1(NA)) genomes shared greater than 96% sequence identity with the European ENTV-1 sequence (ENTV-1(EU)). Most of the amino acid differences were found in Orf-x, which in the corresponding ENTV-1(EU) genome is truncated by 44 amino acids. Apart from Orf-x, the long terminal repeat (LTR) is where the majority of differences between ENTV-1(NA) and ENTV-1(EU) reside. Overall, there was an unusually high degree of amino acid conservation among the isolates suggesting that ENTV-1 is under stabilizing selection and K(a)/K(s) ratios calculated for each of the viral genes support this hypothesis. The unusually high degree of genetic stability of the ENTV-1 genome enabled us to develop a hemi-nested PCR assay for detection of ENTV-1 in clinical samples. Additionally, multiple nasal tumor cell clones were established and while most had lost the provirus by passage 5; one polyclonal line retained the provirus and attempts are being made to culture these cells. These tumor cells, the first of their kind, may provide a system for studying ENTV-1 in vitro. This work represents an important step in the study of ENTV and sets the foundation for the construction of an infectious molecular clone of ENTV-1.
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Affiliation(s)
- Scott R Walsh
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Yang SH, Cheng PH, Sullivan RT, Thomas JW, Chan AWS. Lentiviral integration preferences in transgenic mice. Genesis 2009; 46:711-8. [PMID: 18821598 DOI: 10.1002/dvg.20435] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lentiviral gene transfer has a significant impact on the development of biomedical research. One of the most important features of lentiviruses is the capability to infect both dividing and nondividing cells. However, little is known whether integration preference exists, specifically in early embryos. An in-depth genome analysis on 112 independent lentiviral integration sites from 43 transgenic founder mice was performed to determine if there are preferable sites for lentiviral integration in early embryonic genome. Our results demonstrated that lentiviruses were biased in integrating within intragenic regions, especially in the introns. However, no integration preference was found associated with specific chromosomes, repetitive elements, or CpG islands, nor was there any preference for integrating at close proximity to transcription start sites. Our findings suggested that lentiviruses were biased to integrate into the intragenic regions of early embryonic genome of mouse.
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Affiliation(s)
- Shang-Hsun Yang
- Division of Neuroscience, Yerkes National Primate Research Center, Emory University, 954 Gatewood Road N.E., Atlanta, GA 30329, USA
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Leroux C, Girard N, Cottin V, Greenland T, Mornex JF, Archer F. Jaagsiekte Sheep Retrovirus (JSRV): from virus to lung cancer in sheep. Vet Res 2007; 38:211-28. [PMID: 17257570 DOI: 10.1051/vetres:2006060] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Accepted: 11/23/2006] [Indexed: 01/16/2023] Open
Abstract
Jaagsiekte Sheep Retrovirus (JSRV) is a betaretrovirus infecting sheep. This virus is responsible for a pulmonary adenocarcinoma, by transformation of epithelial cells from the bronchioli and alveoli. This animal cancer is similar to human bronchioloalveolar cancer (BAC), a specific form of human lung cancer for which a viral aetiology has not yet been identified. JSRV interacts with target cells through the membrane receptor Hyal2. The JSRV genome is simple and contains no recognised oncogene. It is now well established that the viral envelope protein is oncogenic by itself, via the cytoplasmic domain of the transmembrane glycoprotein and some domains of the surface glycoprotein. Activation of the PI3K/Akt and MAPK pathways participates in the envelope-induced transformation. Tumour development is associated with telomerase activation. This review will focus on the induction of cancer by JSRV.
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Affiliation(s)
- Caroline Leroux
- Université de Lyon 1, INRA, UMR754, Ecole Nationale Vétérinaire de Lyon, IFR 128, F-69007, Lyon, France.
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Wootton SK, Metzger MJ, Hudkins KL, Alpers CE, York D, DeMartini JC, Miller AD. Lung cancer induced in mice by the envelope protein of jaagsiekte sheep retrovirus (JSRV) closely resembles lung cancer in sheep infected with JSRV. Retrovirology 2006; 3:94. [PMID: 17177996 PMCID: PMC1764900 DOI: 10.1186/1742-4690-3-94] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Accepted: 12/19/2006] [Indexed: 11/23/2022] Open
Abstract
Background Jaagsiekte sheep retrovirus (JSRV) causes a lethal lung cancer in sheep and goats. Expression of the JSRV envelope (Env) protein in mouse lung, by using a replication-defective adeno-associated virus type 6 (AAV6) vector, induces tumors resembling those seen in sheep. However, the mouse and sheep tumors have not been carefully compared to determine if Env expression alone in mice can account for the disease features observed in sheep, or whether additional aspects of virus replication in sheep are important, such as oncogene activation following retrovirus integration into the host cell genome. Results We have generated mouse monoclonal antibodies (Mab) against JSRV Env and have used these to study mouse and sheep lung tumor histology. These Mab detect Env expression in tumors in sheep infected with JSRV from around the world with high sensitivity and specificity. Mouse and sheep tumors consisted mainly of well-differentiated adenomatous foci with little histological evidence of anaplasia, but at long times after vector exposure some mouse tumors did have a more malignant appearance typical of adenocarcinoma. In addition to epithelial cell tumors, lungs of three of 29 sheep examined contained fibroblastic cell masses that expressed Env and appeared to be separate neoplasms. The Mab also stained nasal adenocarcinoma tissue from one United States sheep, which we show was due to expression of Env from ovine enzootic nasal tumor virus (ENTV), a virus closely related to JSRV. Systemic administration of the AAV6 vector encoding JSRV Env to mice produced numerous hepatocellular tumors, and some hemangiomas and hemangiosarcomas, showing that the Env protein can induce tumors in multiple cell types. Conclusion Lung cancers induced by JSRV infection in sheep and by JSRV Env expression in mice have similar histologic features and are primarily characterized by adenomatous proliferation of peripheral lung epithelial cells. Thus it is unnecessary to invoke a role for insertional mutagenesis, gene activation, viral replication, or expression of other viral gene products in sheep lung tumorigenesis, although these processes may play a role in other clinically less important sequelae of JSRV infection such as metastasis observed with variable frequency in sheep.
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Affiliation(s)
- Sarah K Wootton
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Michael J Metzger
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Kelly L Hudkins
- Department of Pathology, University of Washington, Seattle, Washington 98195, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington 98195, USA
| | - Denis York
- Molecular Diagnostic Services, Westville 3630, South Africa
| | - James C DeMartini
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, USA
| | - A Dusty Miller
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
- Department of Pathology, University of Washington, Seattle, Washington 98195, USA
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BAC Consensus Conference, November 4???6, 2004: Epidemiology, Pathogenesis, and Preclinical Models. J Thorac Oncol 2006. [DOI: 10.1097/01243894-200611001-00002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Christiani DC, Pao W, DeMartini JC, Linnoila RI, Malkinson AM, Onn A, Politi KA, Sharp M, Kim K. BAC Consensus Conference, November 4–6, 2004: Epidemiology, Pathogenesis, and Preclinical Models. J Thorac Oncol 2006. [DOI: 10.1016/s1556-0864(15)30002-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Caporale M, Cousens C, Centorame P, Pinoni C, De las Heras M, Palmarini M. Expression of the jaagsiekte sheep retrovirus envelope glycoprotein is sufficient to induce lung tumors in sheep. J Virol 2006; 80:8030-7. [PMID: 16873259 PMCID: PMC1563803 DOI: 10.1128/jvi.00474-06] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary adenocarcinoma (OPA). The expression of the JSRV envelope (Env) alone is sufficient to transform a variety of cell lines in vitro and induce lung cancer in immunodeficient mice. In order to determine the role of the JSRV Env in OPA tumorigenesis in sheep, we derived a JSRV replication-defective virus (JS-RD) which expresses env under the control of its own long terminal repeat (LTR). JS-RD was produced by transiently transfecting 293T cells with a two plasmid system, involving (i) a packaging plasmid, with the putative JSRV packaging signal deleted, expressing the structural and enzymatic proteins Gag, Pro, and Pol, and (ii) a plasmid which expresses env in trans for JS-RD particles and provides the genomes necessary to deliver JSRV env upon infection. During the optimization of the JS-RD system we determined that both R-U5 (in the viral 5' LTR) and the env region are important for JSRV particle production. Two independent experimental transmission studies were carried out with newborn lambs. Four of five lambs inoculated with JS-RD showed OPA lesions in the lungs at various times between 4 and 12 months postinoculation. Abundant expression of JSRV Env was detected in tumor cells of JS-RD-infected animals and PCR assays confirmed the presence of the deleted JS-RD genome. These data strongly suggest that the JSRV Env functions as a dominant oncoprotein in the natural immunocompetent host and that JSRV can induce OPA in the absence of viral spread.
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Affiliation(s)
- Marco Caporale
- Institute of Comparative Medicine, University of Glasgow Veterinary School, 464 Bearsden Road, Glasgow G61 1QH, Scotland
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Abstract
Retroviruses have played profound roles in our understanding of the genetic and molecular basis of cancer. Jaagsiekte sheep retrovirus (JSRV) is a simple retrovirus that causes contagious lung tumors in sheep, known as ovine pulmonary adenocarcinoma (OPA). Intriguingly, OPA resembles pulmonary adenocarcinoma in humans, and may provide a model for this frequent human cancer. Distinct from the classical mechanisms of retroviral oncogenesis by insertional activation of or virus capture of host oncogenes, the native envelope (Env) structural protein of JSRV is itself the active oncogene. A major pathway for Env transformation involves interaction of the Env cytoplasmic tail with as yet unidentified cellular adaptor(s), leading to the activation of PI3K/Akt and MAPK signaling cascades. Another potential mechanism involves the cell-entry receptor for JSRV, Hyaluronidase 2 (Hyal2), and the RON receptor tyrosine kinase, but the exact roles of these proteins in JSRV Env transformation remain to be better understood. Recently, a mouse model of lung cancer induced by JSRV Env has been developed, and the tumors in mice resemble those seen in sheep infected with JSRV and in humans. In this review, we summarize recent progress in our understanding the molecular mechanisms of oncogenic transformation by JSRV Env protein, and discuss the relevance to human lung cancer.
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Affiliation(s)
- S-L Liu
- Department of Microbiology and Immunology, McGill University, Montreal, Canada.
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