Primary PCs cultivated ex vivo released lower levels of cGAMP compared to MM cell lines, while Dox treatment had unpredictable effect on their viability; for this reason, in order to detect a possible difference in cGAMP extracellular level upon CD38 inhibition, we treated PCs with DMSO or CD38i in the absence of Dox, in serum-free medium enriched with IL-3, IL-6, and MnCl2, which boosts cGAS activation.30 This evidence concerns the gene CD38 and Miyoshi myopathy.