Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-2-28
pubmed:abstractText
Breast cancer is the second leading cause of cancer death in North American women. There is considerable need for reliable prognostic markers to assist clinicians in making management decisions. Although a variety of factors have been tested, only tumor stage, grade, size, hormone receptor status, and S-phase fraction are used on a routine basis. The cell cycle is governed by a family of cyclin-dependent kinases (cdks), which are regulated by associated cyclins and by phosphorylation. p27Kip1, a cyclin-dependent kinase inhibitor, regulates progression from G1 into S phase by binding and inhibiting cyclin/cdks. p27Kip1 protein levels and/or activity are upregulated by growth inhibitory cytokines including transforming growth factor-beta (TGF-beta) and, thus, provide an important link between extracellular regulators and the cell cycle. Loss of p27Kip1, a negative cell-cycle regulator, may contribute to oncogenesis and tumor progression. However, p27Kip1 mutations in human tumors are extremely rare. We have demonstrated by immunohistochemistry that p27Kip1 protein levels are reduced in primary breast cancers and that this is associated with tumor progression in both in situ and invasive lesions. This was confirmed by western analysis, reflected in increased G1/S-phase cyclin-dependent kinase activities and shown to be regulated posttranscriptionally by in situ hybridization. Furthermore, on multivariate analysis, low p27Kip1 is a predictor of reduced disease-free survival. This simple and reliable immunohistochemical assay may become a routine part of breast cancer evaluation and may influence patient management.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1078-8956
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
227-30
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Decreased levels of the cell-cycle inhibitor p27Kip1 protein: prognostic implications in primary breast cancer.
pubmed:affiliation
Department of Pathology, Sunnybrook Health Science Center, Toronto, Ontario, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't