Study of the mechanisme of homing of myeloma cells to the bone marrow: study in the 5T2 MM model

Multiple myeloma (MM) is a B cell malignancy characterised by the monoclonal expansion of plasma cells. One of their properties is their specific localisation in the bone marrow (BM). Our group has already demonstrated that MM cells originate extramedullary. This implies a specific homing of the MM cells to the BM. The aim of this project is to investigate the key mechanisms responsible for the high selectivity of this process. A mouse MM model was selected. In our previous work we demonstrated that these mouse MM cells have properties analogous to that of human MM cells. The main advantage of this model is that the MM cells can be manipulated and followed in vivo. Furthermore syngeneic cocultures are possible. In the project proposed here we will determine whether the MM cells can also enter other organs. If not, this implies a selective transendothelial migration or the selective lysis of the cells in the non-bone marrow organs. On the other hand, the bone marrow might provide an exclusive micro-environment inducing the proliferation of the MM cells. The factors responsible for such specific mechanisms will be investigated.