Linked Life Data

1394197

Source:http://linkedlifedata.com/resource/pubmed/id/1394197

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1992-11-10
pubmed:abstractText
We found previously that mouse mammary epithelial cells cultured in the presence of the mammogenic hormones progesterone and prolactin and treated with the carcinogen N-methyl-N-nitrosourea produced a high frequency of hyperplastic alveolar nodules and carcinomas with squamous metaplasia upon transplantation to syngeneic mice. The majority of these mammary transformants had an activated c-Ki-ras proto-oncogene with a specific point mutation in codon 12 (G35 to A35). To determine whether these in vitro findings parallel mammary carcinogenesis in vivo, virgin female mice were pituitary isografted to increase their circulating levels of progesterone and prolactin. The pituitary isograft results in an increase in proliferation, leading to lobulo-alveolar development and differentiation of the mammary epithelial cells. Five weeks after pituitary isografting, the mice were treated with a single injection of N-methyl-N-nitrosourea (50 micrograms/g body weight). Greater than 90% of the N-methyl-N-nitrosourea-treated mice developed mammary carcinomas between 3 and 7 months after treatment. The majority (75%) of the carcinomas had histopathology identical to that of tumors induced in vitro in the presence of progesterone and prolactin. A number of the mammary cancers (17%) induced in pituitary-isografted mice also had the identical point mutation in the c-Ki-ras proto-oncogene found in the in vitro studies. These results suggest that the hormonal milieu around the time of carcinogen exposure affects not only the incidence and phenotype of the mammary transformants but also the molecular events associated with mammary carcinogenesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
52
pubmed:geneSymbol
c-Ha-ras
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5732-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Incidence of c-Ki-ras activation in N-methyl-N-nitrosourea-induced mammary carcinomas in pituitary-isografted mice.
pubmed:affiliation
Department of Molecular and Cell Biology, University of California, Berkeley 94720.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't