TGFB1 and plasma cell myeloma: Some may contribute to myeloma cell ‘‘tolerance,” including myeloma-derived cytokines such as transforming growth factor-b (TGF-b), which suppresses B cells and T cells via inhibition of interleukin-2 (IL-2) autocrine pathways, inadequate antigen presentation, resistance to NK cell lysis, and defective T, B, and NK cells [8].