To further investigate the dependence of MM cells on IKZF1 or IKZF3 expression for survival and elucidate the mechanism of action of lenalidomide and pomalidomide, we stably transduced lenalidomide- and pomalidomide-sensitive MM1.S and U266 cells for inducible expression of IKZF1 or IKZF3 shRNA (designated shIKZF1 or shIKZF3, respectively). The gene discussed is IKZF1; the disease is Miyoshi myopathy.