01A inhibits various APRIL-induced signaling cascades and further blocks APRIL-induced adhesion and migration in MM cells. (A) MM1R cells were serum starved, pretreated with 01A, and stimulated with APRIL (100 ng/mL). Cell lysates were made and subjected to immunoblotting with specific Abs. MM1S and H929 cells were also treated with indicated reagents for 4 hours. (B,D) Cell lysates and (C) mRNA were assayed by immunoblotting and real-time qRT-PCR, respectively. (D) NF-κB DNA binding activity assays were performed in cell lysates (right). (E) MM1S and H929 cells, (F) as well as CD138⁺ patient MM cells, were subjected to adhesion assays on BMSC-coated plates, in the presence or absence of 01A and APRIL. (G) H929 and INA6 MM cells were incubated with 01A in APRIL-induced migration assays.