Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1994-9-15
pubmed:abstractText
Bovine papillomavirus type 4 (BPV-4) is the aetiological agent of epithelial papillomas of the upper alimentary canal in cattle. These benign tumours can become a focus for transformation to squamous cell carcinomas in animals feeding on bracken fern. Strong epidemiological evidence suggests that the progression to malignancy is due to the interplay between BPV-4 and mutagenic and immunosuppressing chemicals present in the fern. The carcinomas of the upper alimentary canal are often accompanied by adenomas and adenocarcinomas of the lower intestine and bracken-grazing animals are also heavily immunosuppressed. To elucidate the individual roles and the concerted action of the viral and chemical factors involved in tumorigenesis and malignant conversion, we attempted to reproduce experimentally the cancer syndrome observed in the field. Florid persistent papillomatosis of the upper alimentary canal was reproduced in animals infected with BPV-4 and immunosuppressed either by a diet of bracken or by treatment with azathioprine; cancer of the upper alimentary tract or of the lower intestine developed only in animals infected with virus and fed on bracken fern. As in field cases, BPV-4 DNA was detected in papillomas but not in cancers. We conclude that immunosuppression is necessary for persistence and spread of viral papillomas, that the fern mutagens are responsible for neoplastic conversion of papilloma cells, and that continuous expression of viral functions is not required for the maintenance of the malignant state.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0143-3334
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1597-601
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Experimental reproduction of the papilloma-carcinoma complex of the alimentary canal in cattle.
pubmed:affiliation
Beatson Institute for Cancer Research, CRC Beatson Laboratories, Glasgow, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't