Linked Life Data

15748640

Source:http://linkedlifedata.com/resource/pubmed/id/15748640

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2005-3-7
pubmed:abstractText
Exposure to (solar) UVB radiation gives rise to mutations in the p53 tumor suppressor gene that appear to contribute to the earliest steps in the molecular cascade towards human and murine skin cancer. To examine in more detail the role of p53, we studied UVB-induced carcinogenesis in hairless p53 knock-out mice. The early onset of lymphomas as well as early wasting of mice interfered with the development of skin tumors in p53 null-mice. The induction of skin tumors in the hairless p53+/- mice was accomplished by daily exposure to two different UV-doses of approximately 450 J/m2 and 900 J/m2 from F40 lamps corresponding to a fraction of about 0.4 and 0.8 of the minimal edemal dose. Marked differences in skin carcinogenesis were observed between the p53+/- mice and their wild type littermates. Firstly, at 900 J/m2, tumors developed significantly faster in the heterozygotes than in wild types, whereas at 450 J/m2 there was hardly any difference, suggesting that only at higher damage levels loss of one functional p53 allele is important. Secondly, a large portion (25%) of skin tumors in the heterozygotes were of a more malignant, poorly differentiated variety of squamous cell carcinomas, i.e. spindle cell carcinomas, a tumor type that was rarely observed in daily UV exposed wild type hairless mice. Thirdly, the p53 mutation spectrum in skin tumors in heterozygotes is quite different from that in wild types. Together these results support the notion that a point mutation in the p53 gene impacts skin carcinogenesis quite differently than allelic loss: the former is generally selected for in early stages of skin tumors in wild type mice, whereas the latter enhances tumor development only at high exposure levels (where apoptosis becomes more prevalent) and appears to increase progression (to a higher grade of malignancy) of skin tumors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0027-5107
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
571
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
81-90
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Dose-dependent effects of UVB-induced skin carcinogenesis in hairless p53 knockout mice.
pubmed:affiliation
National Institute of Public Health and Environment, Laboratory of Toxicology, Pathology and Genetics, Department of Carcinogenesis Mutagenesis and Aging, Bilthoven, The Netherlands. henk.van.kranen@rivm.nl
pubmed:publicationType
Journal Article