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Sub-category:
Tumor/Cell Biology
Category:
Tumor Biology
Meeting:
2009 ASCO Annual Meeting
Session Type and Session Title:
General Poster Session, Tumor Biology and Human Genetics
Abstract No:
11103
Citation:
J Clin Oncol 27:15s, 2009 (suppl; abstr 11103)
Author(s):
A. Azab, F. Azab, J. Runnels, A. M. Roccaro, J. L. Magnani, A. Sarkar, K. C. Anderson, C. P. Lin, I. M. Ghobrial; Dana-Farber Cancer Institute, Boston, MA; GlycoMimetics Inc.; Massachusetts General Hospital, Boston, MA
Abstract Disclosures
Faculty and Discussant Disclosures
Annual Meeting Planning Committee Disclosures
2009 Annual Meeting Proceedings Part I Errata
Abstracts that were granted an exception in accordance with ASCO's Conflict of Interest Policy are designated with a caret symbol (^) here and in the printed Proceedings.
Abstract:
Background: Multiple myeloma (MM) is characterized by the disseminated involvement of the bone-marrow (BM), and its progression involves a continuous circulation of the MM cells (MMCs) in the peripheral blood and homing back to the BM. Selectins are adhesion molecules involved in the primary interaction of lymphocytes with the endothelial cells (ECs) of blood vessels. In this study we studied the role selectins in the pathogenesis of MM. Methods: We have characterized the expression of E, L and P-selectins and their ligands on MM cell lines, patient sample and plasma cells from normal subjects (NPCs). We have tested the effect of blockade of each of the selectins and selectin-ligands on the interaction of MMCs with ECs. Moreover, we tested the effect of a pan selectin inhibitor on MMCs adhesion to ECs, and trans-well (through filter) and trans-endothelial SDF1-induced migration in vitro, and characterized its effect on cytoskeletal signaling induced by the interaction of MMCs and ECs. Moreover, we have tested the effect of the inhibitor on homing of MMCs to the BM in mice using in vivo flow cytometry to detect the number of circulating cells, and in vivo confocal microscopy to directly visualize the homing. Results: All MM cell lines and patient samples had low expression of all selectins and high expression of L and P, but not E, selectin ligands. While NPCs showed low expression of all selectins and ligands. Blockade of L and P-selectin ligands reduced the interaction of MMCs with ECs in vitro, while blockade of E-selectin ligand or any of selectins did not show any effect. The pan-selectin inhibitor reduced the interaction of MMCs with ECs in vitro, did not alter their SDF1-induced migration through filter, but reduced significantly the migration through ECs. The inhibitor inhibited the activation of FAK and ERK induced by interaction of MMCs and ECs. Moreover, the selectin inhibitor extending the circulation time of MM cells in mice, and reduced the homing of MMCs. Conclusions: We found that L and P selectin ligands are highly expressed in MMCs compared to NPCs, and that those play a major role in homing of MMCs to the BM. Moreover, the pan-selectin inhibitor prevented the homing of MMCs to the BM. This provides a basis for testing the effect of the inhibitor on MM tumor progression and initiation.
 Associated Presentation(s):
Other Abstracts in this Sub-Category:
Abstracts by A. Azab:
Presentations by A. Azab:
Educational Book Manuscripts by A. Azab:
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