ING4 expression in MM patients: relationship with IL-8 and BM angiogenesis. ING4 mRNA expression by CD138⁺ MM cells was evaluated in MM patients (n = 50) in relationship with IL-8 mRNA expression. Box plots represent the median −ΔCt ING4 with the 25th to 75th percentiles in MM patients with low levels of IL-8 mRNA (IL-8 ΔCt: > 0) and high IL-8 mRNA levels (IL-8 ΔCt: < 0) (A). ING4 mRNA levels in CD138⁺ MM were evaluated in relationship with bone marrow (BM) IL-8 plasma levels measured by ELISA in a subgroup of 35 MM patients. Plots represent the −ΔCt value of ING4 in MM patients with low and high BM IL-8 levels (B). The potential relationship between BM IL-8 levels and ΔCt ING4 values was analyzed in MM patients by the Spearman 2-tailed test analysis (C). BM angiogenesis was evaluated in bone biopsies of 28 MM patients as described in “BM angiogenesis evaluation.” Plots represent the −ΔCt value of ING4 in MM patients with low and high microvascular density (MVD) (D).