In vitro migratory aberrancies of mesenchymal stem cells derived from multiple myeloma patients only partially modulated by bortezomib.

Recent studies indicated that bone marrow mesenchymal stem cells (BM-MSCs) derived from multiple myeloma (MM) patients were different from those of normal subjects in a variety of aspects. However, it is largely unknown whether BM-MSCs derived from MM patients display any aberrant chemotactic migration. To this aim, we compared the chemotactic migration of BM-MSCs derived from MM patients with those from normal subjects. Our results showed that BM-MSCs derived from MM patients migrated more vigorously to myeloma cell line. Furthermore, proteasome inhibitor bortezomib was showed to suppress chemotactic migration of BM-MSCs whatever their origins. However, although the chemotactic migration of BM-MSCs derived from MM patients to myeloma cell line was more significantly suppressed by bortezomib treatment, migration to SDF-1 or FBS of BM-MSCs was less compromised. Both SDF-1 and TNF-α enhanced phosphorylation of iκ-Bα in BM-MSCs. Although bortezomib significantly inhibited the iκ-Bα phosphorylation by SDF-1, it had little effect on iκ-Bα phosphorylation by TNF-α. Collectively, our results suggested that aberrant chemotactic migration of BM-MSCs derived from MM patients and the possible migration-regulatory role of bortezomib treatment.