IL6 and acute myeloid leukemia: Third, supra-additive levels (i.e., cytokine levels in coculture supernatants exceeding the summarized levels for MSCs and AML cells cultured alone) were seen for several cytokines and reached statistical significance (Wilcoxon’s signed-rank tests, p ≤ 0.005 if not stated otherwise) when comparing the overall results for CCL3, CCL4 (p = 0.043), CXCL1, CXCL5, CXCL8, CXCL10, CXCL11 (p = 0.014), IL-1β, IL-6, IL-10, TNFα (p = 0.037), bFGF, G-CSF, GM-CSF, MMP-1, and MMP-2.