Expression of mTOR signaling pathway markers in prostate cancer progression
Article first published online: 1 MAY 2006
Copyright © 2006 Wiley-Liss, Inc.
Volume 66, Issue 11, pages 1203–1212, 1 August 2006
How to Cite
Kremer, C. L., Klein, R. R., Mendelson, J., Browne, W., Samadzedeh, L. K., Vanpatten, K., Highstrom, L., Pestano, G. A. and Nagle, R. B. (2006), Expression of mTOR signaling pathway markers in prostate cancer progression. Prostate, 66: 1203–1212. doi: 10.1002/pros.20410
- Issue published online: 22 JUN 2006
- Article first published online: 1 MAY 2006
- Manuscript Accepted: 13 DEC 2005
- Manuscript Received: 3 OCT 2005
- NIH. Grant Numbers: T32CA09213, P01CA56666
- prostate tissue array;
- prostate cancer
The PI3K/AKT/mTOR pathway is central to prostate cancer progression. A preliminary investigation of immuno-histochemical expression of mammalian target of rapamycin (mTOR) pathway markers was undertaken to identify patterns of expression in prostate tissue.
Immunohistochemistry was performed on a custom-made prostate tissue array. Mean long scores and variability of long scores for each marker were recorded for normal lumenal cells, prostate intraepithelial neoplasia (PIN), and cancer.
Expression of PTEN decreased and mTOR signaling pathway markers increased in PIN and in cancer as compared to normal cells in the majority of samples. Overexpression of 4E-BP1 and p-4E-BP1 was observed in PIN and cancer. However, in cancer, the overexpression of 4E-BP1 was significantly higher than with any other marker.
Results suggest that 4E-BP1 overexpression is strongly associated with prostate cancer, especially when combined with PTEN and mTOR expression data. Hierarchical clustering analysis utilizing PTEN, mTOR, and 4E-BP1 separated normal from cancer cell populations in most cases. Prostate © 2006 Wiley-Liss, Inc.