Molecular characterization of cadherin expression and function in prostate carcinoma

Persistent Link:
http://hdl.handle.net/10150/279962
Title:
Molecular characterization of cadherin expression and function in prostate carcinoma
Author:
Tran, Nhan Le
Issue Date:
2002
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The epithelial cytoarchitecture and function in the prostate gland are maintained in part by the E-cadherin/catenin complex. In human prostate adenocarcinoma, an association between the loss of E-cadherin, increased Gleason score, and extracapsular dissemination has been observed. Further characterizations of human prostate carcinoma cell lines show loss of E-cadherin and expression of N-cadherin in poorly differentiated prostate carcinoma cell lines. N-cadherin expression correlates with an invasive phenotype in cancer cells and mediates the interactions between malignant tumor cells and N-cadherin expressing cells, such as prostate stromal fibroblasts. Additionally, N-cadherin-mediated intercellular adhesions generate a compensatory mechanism that promotes anchorage-independent growth and suppresses apoptosis through a phosphatidylinositol 3-kinase/Akt/protein kinase B survival pathway. Activated Akt results in the phosphorylation of two downstream substrates, Bad and CREB, to regulate Bcl-2 protein stability and bcl-2 transcription, respectively. Under serum deprivation, N-cadherin intercellular adhesion stimulates a 4-fold increase in bcl-2 mRNA expression resulting in a 3.5-fold increase in Bcl-2 protein expression, while the cellular level of proapoptotic protein Bax remains constant. Following N-cadherin homophilic adhesion the phosphatidylinositol 3-kinase p85 subunit is found in immunoprecipitates of the N-cadherin/catenin complex. The recruitment of phosphatidylinositol 3-kinase is dependent on both N-cadherin homophilic adhesion and N-cadherin binding to an intact actin cytoskeleton. These results suggest that the association of the N-cadherin/catenin complex with the actin cytoskeleton acts as a scaffold to localize the activation of phosphatidylinositol 3-kinase/Akt signaling pathway at adherens junctions. The identification of outside-in signal transduction mediated by N-cadherin adhesion provides new information on anti-apoptotic cell-cell adhesion mechanisms enhancing the activity of the phosphatidylinositol 3-kinase/Akt cell survival pathway in metastatic prostate carcinoma. Collectively, these observations indicate that alterations in cadherin expression play a role in prostate cancer progression that may have a profound affect on metastatic cell survival.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Biology, Cell.; Health Sciences, Medicine and Surgery.; Health Sciences, Oncology.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Cancer Biology
Degree Grantor:
University of Arizona
Advisor:
Heimark, Ronald

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleMolecular characterization of cadherin expression and function in prostate carcinomaen_US
dc.creatorTran, Nhan Leen_US
dc.contributor.authorTran, Nhan Leen_US
dc.date.issued2002en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe epithelial cytoarchitecture and function in the prostate gland are maintained in part by the E-cadherin/catenin complex. In human prostate adenocarcinoma, an association between the loss of E-cadherin, increased Gleason score, and extracapsular dissemination has been observed. Further characterizations of human prostate carcinoma cell lines show loss of E-cadherin and expression of N-cadherin in poorly differentiated prostate carcinoma cell lines. N-cadherin expression correlates with an invasive phenotype in cancer cells and mediates the interactions between malignant tumor cells and N-cadherin expressing cells, such as prostate stromal fibroblasts. Additionally, N-cadherin-mediated intercellular adhesions generate a compensatory mechanism that promotes anchorage-independent growth and suppresses apoptosis through a phosphatidylinositol 3-kinase/Akt/protein kinase B survival pathway. Activated Akt results in the phosphorylation of two downstream substrates, Bad and CREB, to regulate Bcl-2 protein stability and bcl-2 transcription, respectively. Under serum deprivation, N-cadherin intercellular adhesion stimulates a 4-fold increase in bcl-2 mRNA expression resulting in a 3.5-fold increase in Bcl-2 protein expression, while the cellular level of proapoptotic protein Bax remains constant. Following N-cadherin homophilic adhesion the phosphatidylinositol 3-kinase p85 subunit is found in immunoprecipitates of the N-cadherin/catenin complex. The recruitment of phosphatidylinositol 3-kinase is dependent on both N-cadherin homophilic adhesion and N-cadherin binding to an intact actin cytoskeleton. These results suggest that the association of the N-cadherin/catenin complex with the actin cytoskeleton acts as a scaffold to localize the activation of phosphatidylinositol 3-kinase/Akt signaling pathway at adherens junctions. The identification of outside-in signal transduction mediated by N-cadherin adhesion provides new information on anti-apoptotic cell-cell adhesion mechanisms enhancing the activity of the phosphatidylinositol 3-kinase/Akt cell survival pathway in metastatic prostate carcinoma. Collectively, these observations indicate that alterations in cadherin expression play a role in prostate cancer progression that may have a profound affect on metastatic cell survival.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectBiology, Cell.en_US
dc.subjectHealth Sciences, Medicine and Surgery.en_US
dc.subjectHealth Sciences, Oncology.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineCancer Biologyen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorHeimark, Ronalden_US
dc.identifier.proquest3050324en_US
dc.identifier.bibrecord.b42724168en_US
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