IFN-α and -β induce Apo2L expression in MM.

(A) U266 cells were treated with IFN-β, and the steady state mRNA expression was analyzed by multiprobe RNase protection assay for caspase 8 (casp. 8), Fas, DR4, DR5, Apo2L, and, as a control, L32, as described33,38 and detailed in “Materials and methods.” Apo2L protein levels were determined for U266 cells (B) and plasma cells of MM patients (C) treated with IFNs for 24 hours and then subjected to Western blotting using antibodies against Apo2L, and as a control, β-actin.