TBC1D4 and plasma cell myeloma: Quantitative RT-PCR performed on a panel of multiple myeloma (MM) cell lines revealed an up-regulation of AS160 at the transcript level in JJN3, KMS11, L363, RPMI8226, and H929 cells (Figure 1A), while MM.1S, U266, and INA6 exhibit low levels of AS160 mRNA expression, comparable to normal B lymphocytes (NBL).