Linked Life Data

12038707

Source:http://linkedlifedata.com/resource/pubmed/id/12038707

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2002-5-31
pubmed:abstractText
Progesterone receptor (PR) mediates the effects of progesterone in mammary tissues and plays a crucial role in normal breast development and in breast cancer. PR proteins are expressed as two isoforms, PRA and PRB, that have different capacities to activate target genes, yet it is unknown whether progesterone action in normal and malignant breast is mediated by PRA and/or PRB. This study determines the relative expression of PRA and PRB in normal breast and in benign, premalignant and malignant archival breast lesions by dual immunofluorescent histochemistry. In normal breast and in proliferative disease without atypia (PDWA) PRA and PRB were co-expressed within the same cells in comparable amounts, implicating both isoforms in progesterone action. In atypical lesions, however, there was a significant increase in predominant expression of PRA or PRB, with lesion progression from the normal state to malignancy. PR isoform predominance, especially PRA predominance, was evident in a high proportion of ductal carcinomas in situ (DCIS) and invasive breast lesions. In the normal breast and in PDWA, the relative expression of PRA and PRB in adjacent cells was homogenous. There was a significant increase in cell-to-cell heterogeneity of PR isoform expression in ADH and DCIS lesions and in the majority of breast cancers. Heterogeneous cell-to-cell expression of PR isoforms occurred prior to overall predominant expression of one isoform in premalignant breast lesions, demonstrating that loss of control of relative PRA:PRB expression is an early event in the development of breast cancer. PRA:PRB ratios within a breast lesion are likely to be important as both markers and effectors of tumor growth and development, and progressively aberrant PR isoform expression may play a role in the etiology of breast cancer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0167-6806
pubmed:author
pubmed:issnType
Print
pubmed:volume
72
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
163-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Loss of co-ordinate expression of progesterone receptors A and B is an early event in breast carcinogenesis.
pubmed:affiliation
Westmead Institute for Cancer Research, University of Sydney, Westmead Hospital, NSW, Australia. patricia_mote@wmi.usyd.edu.au
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't