Novel Coactivators for Androgen Receptor
Abstract
The point of contact between the extracellular matrix (ECM) and specific cell surface proteins of contact between the extracellular matrix (ECM) and specific cell surface proteins (i.e. integrins) occurs at specialized structures termed focal adhesions, which include several signal transduction molecules such as focal adhesion kinase (FAK). Intracellular signaling pathways that are responsive to ECM attachment influence cell proliferation and are altered in cancer cells. For example, FAK is overexpressed in invasive and metastatic human tumors. Furthermore, FAK is elevated in metastatic prostate cancers and preferentially associated with tyrosine-phosphorylated paxillin, a direct target of FAK. We have found that in addition to its localization to focal adhesions, paxillin is also present within nuclei and can target to the nuclear matrix of CV-1 cells, cultured prostate cancer cell lines and human prostate tissue. Furthermore, paxillin functions as a coactivator for androgen receptor and glucocorticoid receptor, but not estrogen receptor and was found to directly interact with the androgen receptor via its carboxyl-terminal LIM domain. Thus, paxillin, a protein that responds to the metastatic state of prostate cancer cells, can directly influence androgen receptor transactivation. Future studies will be directed towards the assessment of ECM effects on this novel nuclear function of paxillin as it relates to androgen action.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2003
- Accession Number
- ADA415941
Entities
People
- Donald B. Defranco
Organizations
- University of Pittsburgh