U266B1 cells co-cultured with normal, overweight, or obese adipocytes increased activation of caspase-8 in response to bortezomib 2.3-fold (normal), 1.2-fold (overweight), and 2.5-fold (obese) higher than non-co-cultured MM cells. The gene discussed is CASP8; the disease is Miyoshi myopathy.