Recently, PSMD14 inhibitors, such as o-phenanthroline (OPA) [7] and CZM [13], were reported to reduce the viability of MM cells by inducing an unfolded protein response (UPR) and stabilizing proteasome substrates, thereby exerting cytotoxicity against even Bz-resistant cancer cells [7,13]. Here, PSMD14 is linked to Miyoshi myopathy.