This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kim, J. Articles by Freeman, M. R. Search for Related Content PubMed PubMed Citation Articles by Kim, J. Articles by Freeman, M. R.

The Phosphoinositide Kinase PIKfyve Mediates Epidermal Growth Factor Receptor Trafficking to the Nucleus

¹ The Urological Diseases Research Center, Children's Hospital Boston; Departments of ² Surgery and Biological Chemistry and Molecular Pharmacology and ³ Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; ⁴ Department of Ophthalmology and Department of Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, South Carolina; and ⁵ Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan

Requests for reprints: Michael R. Freeman, Enders Research Laboratories, Room 1161, 300 Longwood Avenue, Boston, MA 02115. Phone: 617-919-2644; Fax: 617-730-0238; E-mail: michael.freeman{at}childrens.harvard.edu.

ErbB receptor tyrosine kinases can transit to nuclei in tumor cells, where they have been shown to regulate gene expression as components of transcriptional complexes. Quantitative analysis of a human bladder cancer tissue microarray identified nuclear epidermal growth factor receptor (EGFR) in tumor cells and also showed an increased frequency of this histologic feature in cancer relative to normal tissues. This observation suggests a potential role for nuclear EGFR in bladder cancer. We confirmed that EGFR could be induced to transit to nuclei in cultured human bladder cancer cells in response to the urothelial cell growth factor and EGFR ligand heparin-binding EGF-like growth factor (HB-EGF). Mass spectrometric analysis of EGFR immune complexes from a transitional carcinoma cell line (TCCSUP) identified the phosphoinositide kinase, PIKfyve, as a potential component of the EGFR trafficking mechanism. RNA silencing indicated that PIKfyve is a mediator of HB-EGF–stimulated EGFR nuclear trafficking, EGFR binding to the cyclin D1 promoter, and cell cycle progression. These results identify a novel mediator of the EGFR transcription function and further suggest that nuclear EGFR and the lipid kinase PIKfyve may play a role in bladder oncogenesis. [Cancer Res 2007;67(19):9229–37]