In MM, an NF-κB-driven cancer of plasma cells (PCs), our group identified the complex formed by growth arrest and DNA damage inducible beta (GADD45B) and the JNK kinase, mitogen-activated protein kinase kinase 7 (MKK7), as an essential survival module downstream of NF-κB [230,231] and a therapeutic target in MM [229]. The gene discussed is MAPK7; the disease is Miyoshi myopathy.