The phosphoinositide kinase PIKfyve mediates epidermal growth factor receptor trafficking to the nucleus.
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.
Kim
Jayoung
J
The Urological Diseases Research Center, Children's Hospital Boston, MA, USA.
Jahng
Wan Jin
WJ
Di Vizio
Dolores
D
Lee
Julie S
JS
Jhaveri
Raj
R
Rubin
Mark A
MA
Shisheva
Assia
A
Freeman
Michael R
MR
D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000201:enzymology; D019938:Cyclin D1 / Q000235:genetics; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D013058:Mass Spectrometry; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000235:genetics; D015398:Signal Transduction; D014162:Transfection; D001749:Urinary Bladder Neoplasms / Q000201:enzymology* / Q000235:genetics
D034741:RNA, Small Interfering; D019938:Cyclin D1; D019869:Phosphatidylinositol 3-Kinases; C492139:PIKFYVE protein, human; D066246:ErbB Receptors