Neither imatinib nor nilotinib induce a decrease of LTC-IC frequency.

<p>(<b>A</b>)<b>:</b> Influence of a 48-hour pre-culture with imatinib or nilotinib at a final concentration of 1 or 5 µM on LTC-IC frequencies. (<b>B</b>)<b>:</b> LTC-IC generation with TKIs in a 6-week LTC-IC assay. Results are expressed as mean ± SD. n = 3, Student’s paired t tests. CTL: control condition without TKIs.</p

Cell surface expression of VLA-4 and VLA-5 were decreased after a 48 h cell-culture with TKIs while CXCR-4 expression was not affected.

<p>Influence of 48-hour pre-culture in presence of either imatinib or nilotinib on <b>(</b>A<b>):</b> VLA-4 <b>(</b>B<b>):</b> VLA-5 and <b>(</b>C<b>):</b> CXCR-4. Results are expressed as the mean channel fluorescence ratio (MCFR) ± SD. n ≥3, *p<0.05, **p<0.01, ***p<0.001 versus CTL, Student’s paired t tests. CTL: control condition without TKIs.</p

Influence of TKIs on adhesion and migration of human cord blood CD34⁺ cells.

<p>(<b>A</b>)<b>:</b> Adhesion of CD34⁺ cells to retronectin was significantly reduced in presence of the highest doses of TKIs. Results are expressed as the percentage of adherent cells ± SD. n = 10, *p<0.05 versus CTL, Student’s paired t tests. (<b>B</b>)<b>:</b> Migration of human HSCs toward a SDF-1α gradient was not modified by a 48 hour pre-culture period in the presence of TKIs. Results are expressed as the percentage of migrating cells ± SD. n = 4, Student’s paired t tests. CTL: control condition without TKIs.</p

TKIs dramatically decrease CFC formation.

<p>(<b>A</b>)<b>:</b> Influence of a 48-hour pre-culture in the presence of either imatinib or nilotinib on CFC formation. (<b>B</b>)<b>:</b> CFC generation in CFC assays supplemented with TKIs. Results are expressed as mean percentages relative to control experiments without TKIs ± SD. n = 4, *p<0.05, **p<0.005 versus CTL, Student’s paired t tests. CTL: control condition without TKIs.</p

Colony formation in presence of tyrosine kinase inhibitors were decreased due to the inhibition of cell cycle entry.

<p>Human cord blood CD34⁺ were cultured for 48 hours in presence/absence of either imatinib or nilotinib and then stained with propidium iodide using the CycleTEST™ Plus DNA Reagent Kit. Results are expressed as mean percentages relative to control experiments without TKIs ± SD. n = 3, *p<0.05, **p<0.01 versus CTL, Student’s paired t tests. CTL: control condition without TKIs.</p

Effects of TKIs in a mouse model of transplantation.

<p>(<b>A</b>)<b>:</b> Daily doses of TKIs for 42 days did not affect bone marrow cellularity. Results are expressed as the mean number of cells per femur ± SD. n ≥8, Student’s unpaired t tests. (<b>B</b>)<b>:</b> Effect of continuous administration of TKIs on bone marrow chimerism. Imatinib did not affect the percentage of human cells in the bone marrow while nilotinib slightly decreased it compared to the control group. Results are expressed as the mean percentage ± SD. n ≥8, *p = 0.0314 versus CTL, Student’s unpaired t tests. CTL: control condition without TKIs.</p

Inhibitory effects of TKIs on c-Kit phosphorylation in human CD34⁺ cord blood HSCs.

<p>The phosphorylated c-Kit receptor was detected by western blot after a 48-hour culture in presence of either imatinib or nilotinib. Representative picture from 4 independent experiments (n = 4).</p

Cumulative incidence of grade II–IV acute GVHD according to day 7 IL-7 plasma levels among nonmyeloablative recipients (P = 0.4) (A).

<p>Cumulative incidence of grade II–IV acute GVHD according to day 14 IL-7 plasma levels among nonmyeloablative recipients (P = 0.18) (B). Cumulative incidence of grade II–IV acute GVHD according to day 7 IL-15 serum levels among nonmyeloablative recipients (P = 0.8) (C). Cumulative incidence of grade II–IV acute GVHD according to day 14 IL-15 serum levels among nonmyeloablative recipients (P = 0.6) (D).</p

Mithramycin Exerts an Anti-Myeloma Effect and Displays Anti-Angiogenic Effects through Up-Regulation of Anti-Angiogenic Factors

<div><p>Mithramycin (MTM), a cytotoxic compound, is currently being investigated for its anti-angiogenic activity that seems to be mediated through an inhibition of the transcription factor SP1. In this study we evaluated its anti-myeloma effects in the syngenic 5TGM1 model <i>in vitro</i> as well as <i>in vivo</i>. <i>In vitro</i>, MTM inhibited DNA synthesis of 5TGM1 cells with an IC50 of 400 nM and induced an arrest in cell cycle progression at the G1/S transition point. Western-blot revealed an up-regulation of p53, p21 and p27 and an inhibition of c-Myc, while SP1 remained unaffected. In rat aortic ring assays, a strong anti-angiogenic effect was seen, which could be explained by a decrease of VEGF production and an up-regulation of anti-angiogenic proteins such as IP10 after MTM treatment. The administration of MTM to mice injected with 5TGM1 decreased 5TGM1 cell invasion into bone marrow and myeloma neovascularisation. These data suggest that MTM displays anti-myeloma and anti-angiogenic effects that are not mediated by an inhibition of SP1 but rather through c-Myc inhibition and p53 activation.</p></div

Patients’ characteristics.

*<p>double blind randomized study: The information of which of these 3 patients (if any) have been given MSC has been given by the director of the Cell Laboratory only to LS (the statistician); TBI, total body irradiation; MMF, mycophenolate mofetil.</p