[Effect of Bone Marrow Mesenchymal Stem Cells in Patients with Multiple Myelima on Migration of Myeloma Cells In Vitro].

OBJECTIVE: To explore the effect of bone marrow mesenchymal stem cells (MSC) in patients with multiple myeloma(MM) on chemotactic migration of myeloma cells in vitro.

METHODS: By in vitro co-culture with diffferent MSC, the myeloma cell U266 was divided into 2 groups: group A in which the U266 cells were co-cultured with normal person MSC (N-MSC) and group B in which the U266 cells were co-cultured with MM-MSC. The expression level of CCR1 in U266 cells, migration rate of U266 cells in Transwell, and the effect of supernantant from co-culture of U266 cells with N-MSC and MM-MSC on the migration in Transwell were compared in condition with or without bortezomib.

RESULTS: After co-culture of U266 cells with N-MSC or MM-MSC, the migration rate of U266 cells in Transwell in B group was higher than that in A group(P<0.05). The difference between 2 groups could not be eliminated after treatment of U266 cells with bortezomib. The CCR1 expression level of U266 cells in B group was higher than that in A group (P<0.05). The culture supernatant of bone marrow MSC showed that in condition without bortezomib the culture supernatant of MSC in MM patients and normal persons both possessed more strong chemotactic ability and enhanced the migration rate of cells in Transwell, compared with SDF-1, meanswhile the culture supernatant in 3 groups reduced the migration rate of cells in condition with bortezomib (P<0.05), but there were no statistical difference in migration rate of U266 cells in Transwell between supernatant of N-MSC and MM-MSC culture (P>0.05), no matter the bortezonib was used or not.

CONCLUSION: The bone marrow MSC in MM patients have same intrinsic defects that affect the chemotaxis of cells in vitro by directly interacting with myeloma cells.