<b>Methods</b>: The effects of extracellular ENO1 on stromal activation and tumor-supportive functions were examined in MM using MM-bone marrow stromal cell (BMSC) co-cultures, lactate production and viability assays, immunoblotting, cytokine analyses, and a subcutaneous xenograft model of bortezomib (BTZ)-resistant MM in male 6-7-week-old NOD.Cg-Prkdc<sup>scid</sup> Il2rg<sup>tm1Vst</sup>/Vst (NPG) mice. Here, PRKDC is linked to Miyoshi myopathy.