Analysis of toll-like receptor (TLR) expression at protein level indicated that TLR1, TLR3, TLR4, TLR7, TLR8, and TLR9, were similarly expressed in most human myeloma cell lines, including L363 and RPMI 8226 cells, as well as in primary cells from MM patients (18). The gene discussed is TLR4; the disease is plasma cell myeloma.