IL-32 is expressed by MM cells, and high expression is correlated with inferior survival. (A) Heat map of top 25 most highly expressed genes as determined by Nanostring analyses in BM-derived CD138⁺ MM cells obtained from patients (n = 8). (B) IL32 mRNA expression was quantified by quantitative PCR in BM-derived CD138⁺ MM cells (n = 40) and MM cell lines (n = 9). Immunoblotting of total cell lysates from MM cell lines (n = 9) (C) and CD138⁺ primary MM cells (n = 6) (D). (E) IL-32 was quantified by ELISA in BM plasma obtained from healthy persons (n = 5; median, 360 pg/mL), patients with monoclonal gammopathy of unknown significance (MGUS; n = 16; median, 565.6 pg/mL), and patients with MM (n = 41; median, 906.5 pg/mL). The differences between the groups are not statistically significant. (F) Survival curves generated from the CoMMpass data (IA8 release) by comparing the IL32 upper 15th percentile (IL-32 expressors; n = 82; median survival, 464 days) with the lower 85th percentile (IL-32 nonexpressors; n = 466; median survival, 914 days). Log-rank P < .0001. Bars indicate median values in panels A and C.