ERN1 and Miyoshi myopathy: To check if bortezomib and CK2 inhibitors could interact in the ER stress pathways and proteotoxicity, we performed WB analysis of Ire1α, total and phospho Ser51 eIF2α and poly-Ub proteins in MM cells upon exposure to bortezomib, CK2 inhibitors or the combination of the two drugs.