Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-12-4
pubmed:abstractText
BRCA2 is central to an utterly diverse biological behavior elicited after integrin-mediated normal and prostate cancer cell adhesion to basement membrane (BM) and extracellular matrix (ECM) proteins. Unlike normal cells, adhesive stimuli in cancer cells activate PI 3-kinase/AKT signaling resulting in BRCA2 degradation and unchecked cancer cell proliferation and metastasis. However, the precise mechanisms involved in normal BRCA2 homeostasis are unknown. We investigated ERK and AKT phosphorylation in normal (PNT1A) and cancer (PC-3) prostate cells after adhesion to ECM and the effects upon BRCA2 and cell proliferation. PNT1A cell adhesion to ECM triggered MAPK/ERK signaling resulting in upregulation of BRCA2 mRNA and protein, with negligible effects upon cell proliferation. Disruption of MAPK/ERK with PD98059 prevented any BRCA2 upregulation inhibiting DNA synthesis below basal levels. PC-3 cells exhibited a defective MAPK/ERK pathway that was unresponsive to adhesion to the ECM, which instead triggered PI 3-kinase/AKT signaling leading to BRCA2 protein depletion and cell proliferation. Reconstitution of MAPK/ERK by recombinant expression of a constitutively active form of MAPK kinase 1 (MEK1) effectively reversed the neoplastic phenotype by increasing BRCA2 expression and preventing any aberrant cell proliferation at rest and upon interaction with ECM proteins. Our results suggest that aberrant loss of MAPK/ERK activity in prostate cancer may play a pivotal role in the malignant phenotype, and provide evidence that interventions aimed at bypassing the signaling block are able to effectively reverse neoplastic unchecked cell proliferation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1019-6439
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
217-24
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Constitutive activation of MAPK/ERK inhibits prostate cancer cell proliferation through upregulation of BRCA2.
pubmed:affiliation
Institute of Biomembranes and Bioenergetics, National Research Council (C.N.R.), 70126 Bari, Italy. l.moro@ibbe.cnr.it
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't