MAPK8 and Miyoshi myopathy: In line with this hypothesis, in each of five heterogeneous MM cell lines and a B lymphoblastoid cell line, the silencing of the NF-κB subunit RelA (DiDonato et al., 2012) triggered JNK activation and apoptosis (Figures S2A–S2C), and blocking this activation with the JNK inhibitor SP600125 effectively protected NF-κB/RelA-silenced MM cells from cell death (Figures S2D and S2E).