Role of BAFF in adhesion and growth of human multiple myeloma cells in the bone marrow microenvironment.

Recent studies have underscored the role of B-cell activating factor (BAFF), a member of the tumor necrosis factor superfamily, in promoting the survival of malignant B cells, including human MM. Since the tumor bone marrow microenvironment plays a crucial role in MM cell growth and survival, we here characterize the functional significance of BAFF in the interaction between MM and bone marrow stromal cells (BMSCs), and further defined molecular mechanisms regulating these processes. We first confirmed the expression of BAFF and its receptors (BCMA, TACI, BAFF-R) on majority of MM cell lines and CD138-purified patient MM cells. Significantly, gene expression profiling revealed increased BCMA expression on newly diagnosed and relapsed MM versus normal plasma cells (p