To obtain insights into the molecular basis of observed metabolic reprogramming, genetically CD38-overexpressing MM cells were analyzed for their total respiratory capacity: as shown in Figure 7A and Figure S10A,B, the measurement of complex I, II, III, and IV activities and protein levels revealed worse capabilities for CD38-modified cells with exposure to FK866, resulting in poorer outcomes. Here, CD38 is linked to Miyoshi myopathy.