Endocrine-Related Cancer 16
(3)
795
-808
DOI: 10.1677/ERC-08-0175
Copyright © 2009 by the Society for Endocrinology
Novel mechanism of IGF-binding protein-3 action on prostate cancer cells: inhibition of proliferation, adhesion, and motility
Petra Massoner,
Daniela Colleselli,
Andrea Matscheski1,
Haymo Pircher1,
Stephan Geley2,
Pidder Jansen Dürr1 and
Helmut Klocker
Department of Urology, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
1 Institute for Biomedical Aging Research, Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck, Austria
2 Department of Molecular Pathophysiology of the Biocenter, Innsbruck Medical University, Fritz-Pregl Straße 3, 6020 Innsbruck, Austria
(Correspondence should be addressed to H Klocker; Email: helmut.klocker{at}uki.at)
IGF-binding protein-3 (IGFBP-3) is a modulator of the IGF-signaling pathway and was described as an anti-cancer agent in prostate cancer. The molecular mechanisms underlying these effects remained, however, largely undefined. We analyzed the influence of recombinant IGFBP-3 on cell proliferation of PC3, Du145, and LNCaP prostate cancer cells. As expected, IGFBP-3 inhibited IGF-stimulated cell proliferation by blocking IGF-mediated proliferation signals, but we observed an IGF-independent inhibitory effect of IGFBP-3 on prostate cancer cell proliferation in long-term cultures. We further investigated the influence of IGFBP-3 on adhesion, motility, and invasion of prostate cancer cells using adhesion assays, live-cell imaging techniques, and matrigel invasion measurements. There was a clear inhibitory effect of IGFBP-3 on tumor cell adhesion to extracellular matrix components in the presence and absence of IGF, whereas cell–cell adhesion was not affected. The same inhibitory effect of IGFBP-3 was determined on cell motility when real-time cell movements were followed. In addition, IGFBP-3 was able to inhibit tumor cell invasion through matrigel. In summary, we show that IGFBP-3 inhibits proliferation, adhesion, migration, and invasion processes of prostate tumor cells. These newly described mechanisms of IGFBP-3 can be of importance for tumor progression and support a role of IGFBP-3 in therapeutic settings.
Copyright © 2009 by the Society for Endocrinology.