Dirk Hose

Baseline characteristics, chromosomal alterations, and treatment affecting prognosis of deletion 17p in newly diagnosed myeloma.

Deletion 17p13, del(17p), is associated with poor outcome in myeloma but some patients show long‐term survival. With the current study we intended to identify factors impacting outcome of such high risk patients. We analyzed 110 newly diagnosed, symptomatic patients with del(17p) detected by fluorescence in situ hybridization (FISH) in CD138‐purified myeloma cells to identify prognostic factors for survival. Age >65 years, ISS III, and elevated LDH negatively impacted survival. Patients with subclonal (10–60% of plasma cells) del(17p) had longer progression‐free survival (PFS) than patients with del(17p) in >60% of plasma cells (26 vs. 19 months, Pu2009=u20090.03). Additional gain of 1q21 was associated with shorter PFS (17 vs. 25 months, Pu2009=u20090.01). Hyperdiploidy did not ameliorate impact of del(17p), but gain 19q13 predicted longer PFS (30 vs. 18 months, Pu2009=u20090.01) and overall survival (50 vs. 29 months, Pu2009=u20090.01). Multivariate analysis in transplant eligible patients (≤65 years) revealed better survival for patients treated with upfront autologous transplantation (hazard ratio, [95% confidence interval]: 0.15 [0.04, 0.58], Pu2009=u20090.006). Application of maintenance therapy was associated with better survival in transplant‐eligible patients (0.30 [0.09, 0.99], Pu2009=u20090.05). We demonstrate heterogeneous outcome of patients with del(17p) according to baseline characteristics and treatment. 19q13 should be included in routine FISH panel, since gains were associated with better survival. Am. J. Hematol. 91:E473–E477, 2016.

The AP-1 transcription factor JunB is essential for multiple myeloma cell proliferation and drug resistance in the bone marrow microenvironment

Despite therapeutic advances, multiple myeloma (MM) remains an incurable disease, predominantly because of the development of drug resistance. The activator protein-1 (AP-1) transcription factor family has been implicated in a multitude of physiologic processes and tumorigenesis; however, its role in MM is largely unknown. Here we demonstrate specific and rapid induction of the AP-1 family member JunB in MM cells when co-cultured with bone marrow stromal cells. Supporting a functional key role of JunB in MM pathogenesis, knockdown of JUNB significantly inhibited in vitro MM cell proliferation and survival. Consistently, induced silencing of JUNB markedly decreased tumor growth in a murine MM model of the microenvironment. Subsequent gene expression profiling revealed a role for genes associated with apoptosis, DNA replication and metabolism in driving the JunB-mediated phenotype in MM cells. Importantly, knockdown of JUNB restored the response to dexamethasone in dexamethasone-resistant MM cells. Moreover, 4-hydroxytamoxifen-induced activation of a JunB-ER fusion protein protected dexamethasone-sensitive MM cells against dexamethasone- and bortezomib-induced cytotoxicity. In summary, our results demonstrate for the first time a specific role for AP-1/JunB in MM cell proliferation, survival and drug resistance, thereby strongly supporting that this transcription factor is a promising new therapeutic target in MM.

Stability of the proteasome inhibitor bortezomib in cell based assays determined by ultra-high performance liquid chromatography coupled to tandem mass spectrometry

Bortezomib represents the first clinically approved proteasome inhibitor for multiple myeloma. Research conducted on its intracellular kinetics in target cells and on possibly related mechanisms of resistance is sparse so far. We therefore developed and validated a highly sensitive ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC/MS/MS) method for bortezomib quantification within cultured myeloma cells and media. Fast gradient UPLC based on a BEH C18 column (1.7 μm particle size) with aqueous formic acid and acetonitrile as mobile phase. Selective extraction procedures using protein precipitation extraction (PPE) and liquid-liquid extraction (LLE) were established and compared. Extracted bortezomib was quantified by positive electrospray tandem mass spectrometry using deuterated D8-bortezomib as internal standard. The calibrated ranges were 0.5-2500 pg per sample. For LLE, overall accuracies varied between 99.2% and 112% (medium) and 89.9% and 111% (cells), while overall precision ranged from 1.13% to 13.0% (medium) and 2.80% to 12.7% (cells), respectively. Recovery rates (cells/medium) were >77%/>65% for LLE and >89%/63% for PPE. Matrix effects were generally lower for LLE compared to PPE. Regardless of the extraction method, retrievable amounts of bortezomib were considerably reduced after 24h of incubation (0.2, 1, 5, and 25 nM). Revealing greater dependence on the extent of acidification, retrieval of bortezomib can be increased distinctly in acidified solution or acidified culture medium. Thus, particular attention needs to be paid to the occurring bortezomib degradation in neutral culture medium since correct quantification of intracellular bortezomib can only be achieved in relation to the corresponding extracellular concentration.

Association between magnetic resonance imaging patterns and baseline disease features in multiple myeloma: analyzing surrogates of tumour mass and biology.

AbstractObjectiveTo assess associations between bone marrow infiltration patterns and localization in magnetic resonance imaging (MRI) and baseline clinical/prognostic parameters in multiple myeloma (MM).MethodsWe compared baseline MM parameters, MRI patterns and localization of focal lesions to the mineralized bone in 206 newly diagnosed MM patients.ResultsA high tumour mass (represented by International Staging System stage III) was significantly associated with severe diffuse infiltration (pu2009=u20090.015) and a higher number of focal lesions (pu2009=u20090.006). Elevated creatinine (pu2009=u20090.003), anaemia (pu2009<u20090.001) and high LDH (pu2009=u20090.001) correlated with severe diffuse infiltration. A salt and pepper diffuse pattern had a favourable prognosis. A higher degree of destruction of mineralized bone (assessed by X-ray or computed tomography) was associated with an increasing number of focal lesions on MRI (pu2009<u20090.001). Adverse cytogenetics (del17p/gain1q21/t(4;14)) were associated with diffuse infiltration (pu2009=u20090.008). The presence of intraosseous focal lesions exceeding the mineralized bone had a borderline significant impact on prognosis.ConclusionsDiffuse bone marrow infiltration on MRI correlates with adverse cytogenetics, lowered haemoglobin values and high tumour burden in newly diagnosed MM whereas an increasing number of focal lesions correlates with a higher degree of bone destruction. Focal lesions exceeding the cortical bone did not adversely affect the prognosis.Key Points• Diffuse MRI correlates with adverse cytogenetics, lowered haemoglobin and high tumour burden.n • Higher numbers of MRI focal lesions correlate with increasing degree of bone destruction.n • Focal lesions exceeding the cortical bone borderline significantly influence survival.n • Moderate/severe diffuse infiltration and more than 23 focal lesions adversely affect survival.

Cellular uptake kinetics of bortezomib in relation to efficacy in myeloma cells and the influence of drug transporters

PurposeDespite overall successful application to multiple myeloma patients, clinical efficacy of the proteasome inhibitor bortezomib is typically challenged by primary and secondary resistance of unknown origin. So far, the potential impact of intracellular concentrations on drug efficacy of bortezomib and the influence of drug transporters are unknown.MethodsWe determined cellular bortezomib kinetics in nine myeloma cell lines using ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry. The potential influence of drug transporters on the uptake kinetics observed in these cell lines was investigated by testing substrate characteristics of bortezomib for several transporters in over-expressing model cells. Additionally, transporter mRNA expression was quantified in myeloma cell lines by real-time polymerase chain reaction (RT-PCR).ResultsAll myeloma cells revealed an extensive intracellular bortezomib accumulation (47.5–183xa0ng/ml) exceeding extracellular concentrations (0.04–0.17xa0ng/ml) by more than factor 1,000. Only organic anion-transporting polypeptide 1B1 facilitated the uptake in over-expressing cells, however, to a negligible extent (factor 1.36). Bortezomib efflux via P-glycoprotein was confirmed by demonstrating reduced sensitivity (IC50 11.6 vs. 2.8xa0ng/ml) and intracellular concentrations (−56.1xa0%) in over-expressing cells compared to controls. RT-PCR revealed a varying but overall weak transporter expression in the studied myeloma cells without any correlation to intracellular concentrations. Although principally valid as demonstrated in the P-glycoprotein over-expressing cell model, there was no significant correlation between intracellular concentrations and bortezomib efficacy in myeloma cell lines.ConclusionDifferences in intracellular concentrations in myeloma cell lines neither result from variable transporter expression nor represent the main factor determining bortezomib efficacy in vitro.

Rationale and design of the German-Speaking Myeloma Multicenter Group (GMMG) trial ReLApsE: a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma

BackgroundDespite novel therapeutic agents, most multiple myeloma (MM) patients eventually relapse. Two large phase III trials have shown significantly improved response rates (RR) of lenalidomide/dexamethasone compared with placebo/dexamethasone in relapsed MM (RMM) patients. These results have led to the approval of lenalidomide for RMM patients and lenalidomide/dexamethasone has since become a widely accepted second-line treatment. Furthermore, in RMM patients consolidation with high-dose chemotherapy plus autologous stem cell transplantation has been shown to significantly increase progression free survival (PFS) as compared to cyclophosphamide in a phase III trial. The randomized prospective ReLApsE trial is designed to evaluate PFS after lenalidomide/dexamethasone induction, high-dose chemotherapy consolidation plus autologous stem cell transplantation and lenalidomide maintenance compared with the well-established lenalidomide/dexamethasone regimen in RMM patients.Methods/DesignReLApsE is a randomized, open, multicenter phase III trial in a planned study population of 282 RMM patients. All patients receive three lenalidomide/dexamethasone cycles and - in absence of available stem cells from earlier harvesting - undergo peripheral blood stem cell mobilization and harvesting. Subsequently, patients in arm A continue on consecutive lenalidomide/dexamethasone cycles, patients in arm B undergo high dose chemotherapy plus autologous stem cell transplantation followed by lenalidomide maintenance until discontinuation criteria are met. Therapeutic response is evaluated after the 3rd (arm Au2009+u2009B) and the 5th lenalidomide/dexamethasone cycle (arm A) or 2xa0months after autologous stem cell transplantation (arm B) and every 3xa0months thereafter (arm Au2009+u2009B). After finishing the study treatment, patients are followed up for survival and subsequent myeloma therapies. The expected trial duration is 6.25xa0years from first patient in to last patient out. The primary endpoint is PFS, secondary endpoints include overall survival (OS), RR, time to best response and the influence of early versus late salvage high dose chemotherapy plus autologous stem cell transplantation on OS.DiscussionThis phase III trial is designed to evaluate whether high dose chemotherapy plus autologous stem cell transplantation and lenalidomide maintenance after lenalidomide/dexamethasone induction improves PFS compared with the well-established continued lenalidomide/dexamethasone regimen in RMM patients. Trial registration: ISRCTN16345835 (date of registration 2010-08-24).

Longitudinal fluorescence in situ hybridization reveals cytogenetic evolution in myeloma relapsing after autologous transplantation

To investigate cytogenetic evolution after upfront autologous stem cell transplantation for newly diagnosed myeloma we retrospectively analyzed fluorescence in situ hybridization results of 128 patients with paired bone marrow samples from the time of primary diagnosis and at relapse. High-risk cytogenetic abnormalities (deletion 17p and/or gain 1q21) occurred more frequently after relapse (odds ratio: 6.33; 95% confidence interval: 1.86–33.42; P<0.001). No significant changes were observed for defined IGH translocations [t(4;14); t(11;14); t(14;16)] or hyperdiploid karyotypes between primary diagnosis and relapse. IGH translocations with unknown partners occurred more frequently at relapse. New deletion 17p and/or gain 1q21 were associated with cytogenetic heterogeneity, since some de novo lesions with different copy numbers were present only in subclones. No distinct baseline characteristics were associated with the occurrence of new high-risk cytogenetic abnormalities after progression. Patients who relapsed after novel agent-based induction therapy had an increased risk of developing high-risk aberrations (odds ratio 10.82; 95% confidence interval: 1.65–127.66; P=0.03) compared to those who were treated with conventional chemotherapy. Survival analysis revealed dismal outcomes regardless of whether high-risk aberrations were present at baseline (hazard ratio, 3.53; 95% confidence interval: 1.53–8.14; P=0.003) or developed at relapse only (hazard ratio, 3.06; 95% confidence interval: 1.09–8.59; P=0.03). Our results demonstrate cytogenetic evolution towards high-risk disease after autologous transplantation and underline the importance of repeated genetic testing in relapsed myeloma (EudraCT number of the HD4 trial: 2004-000944-26).

Osteocyte Regulation of Receptor Activator of NF-κB Ligand/Osteoprotegerin in a Sheep Model of Osteoporosis

Osteoporosis induction in a sheep model by steroid administration combined with ovariectomy recapitulates decreased bone formation and substandard matrix mineralization in patients. Recently, the role of osteocytes has been frequently addressed, with focus on their role in osteoclastogenesis. However, the quantification of receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) signaling in osteocytes was not studied in sheep. The current study reproduced the sheep model of osteoporosis to study the RANKL/OPG ratio correlation to the method of osteoporosis induction. We investigated the induction of osteoporosis after 8 months using 31 female merino land sheep divided into four groups: control, ovariectomy, ovariectomy with dietary limitation, and ovariectomy with dietary limitation and steroid injection. In accordance to previous reports, the present study showed trabecular thinning, higher numbers of apoptotic osteocytes, and imbalanced metabolism, leading to defective mineralization. The global RANKL/OPG ratio in the spine after 8 months of steroid and dietary treatment was not different from that of the control. Interestingly, assessment of the osteocyte-specific RANKL/OPG ratio showed that the steroid-induced osteoporosis in its late progressive phase stimulates RANKL expression in osteocytes. Sclerostin is suggested to induce RANKL expression in osteocytes. Thexa0findings of this study can contribute to further explain the success of sclerostin antibodies in treating osteoporotic patients despite increased osteocyte-expressed RANKL.

B152 First Analysis of HOVON-65/GMMG-HD4 Randomized Phase III Trial Comparing Bortezomib, Doxorubicin, Dexamethasone (PAD) vs. VAD as Induction Treatment Prior to High-dose Melphalan (HDM) in Patients with Newly Diagnosed Multiple Myeloma (MM)

The randomized, open-label, phase III trial HOVON-65/GMMG-HD4 was designed to evaluate the efficacy of bortezomib prior to HDM for response and progression-free survival (PFS) in patients with newly diagnosed MM. The trial was performed in 75 referral centers in the Netherlands and Belgium (HOVON group) and Germany (GMMG group). Patients with Salmon & Durie (SD) stage II or III, age 18-65 years inclusive, were randomly assigned to 3 cycles of VAD (vincristine 0.4 mg, adriamycine 9 mg/m2 days 1-4, dexamethasone 40 mg days 1-4, 9-12, and 17-20) or PAD (bortezomib 1.3 mg/m2 days 1,4,8,11, adriamycine 9 mg/m2 days 1-4, dexamethasone 40 mg days 1-4, 9-12, and 17-20). No thrombosis prophylaxis was given. Stem cells were mobilized using the CAD regimen, including cyclophosphamide 1000 mg/m2 iv day 1, and G-CSF. After induction therapy, all patients were to receive 1 or 2 cycles of high-dose melphalan (HDM) 200 mg/m2 with autologous stem cell rescue followed by maintenance with thalidomide 50 mg daily (VAD arm) or bortezomib, 1.3 mg/m2 once every 2 weeks (PAD arm) for 2 years. Between May 4, 2005 and May 16, 2008, 833 patients were randomized. After the trial was closed, we here report the planned interim analysis data on response after induction and HDM-1 of the initial 300 (150 per arm) randomized patients. The 2 randomization arms were equal for SD stage of disease, ISS stage, and distribution of chromosomal abnormalities. 137 patients (91%) completed PAD or 136 (91%) completed VAD and 132 patients (88%) in each arm completed HDM-1. Full dose bortezomib could be administered in 95% (PAD1), 89% (PAD2) and 85% (PAD3) of patients. Successful stem cell apheresis was achieved in all 137 PAD treated patients who received CAD mobilization . Peripheral polyneuropathy CTC grade 3-4 during PAD vs VAD was 16% vs 6%, while DVT/pulmonary embolism was diagnosed in 3% during VAD and 4% during PAD. Responses were assessed according to EBMT criteria including VGPR and nCR after PAD/VAD, after HDM-1 and best response on protocol treatment. Complete Response (CR/nCR), Very Good Partial Response (VGPR) and Partial Response (PR) in both arms were compared by logistic regression (table 1). Deletion of chromosome 13q or presence of t(4;14) did not have a significant impact on VGPR or (n)CR. We conclude that PAD induces significantly more PR+VGPR+(n)CR as compared with VAD, and that this effect is sustained after HDM-1.

Visfatin alters the cytokine and matrix-degrading enzyme profile during osteogenic and adipogenic MSC differentiation

OBJECTIVESnAge-related bone loss is associated with bone marrow adiposity. Adipokines (e.g., visfatin, resistin, leptin) are adipocyte-derived factors with immunomodulatory properties and might influence differentiation of bone marrow-derived mesenchymal stem cells (MSC) in osteoarthritis (OA) and osteoporosis (OP). Thus, the presence of adipokines and MMPs in bone marrow and their effects on MSC differentiation were analyzed.nnnMETHODSnMSC and ribonucleic acid (RNA) were isolated from femoral heads after hip replacement surgery of OA or osteoporotic femoral neck fracture (FF) patients. Bone structural parameters were evaluated by microcomputed tomography (μCT). MSC were differentiated towards adipocytes or osteoblasts with/without adipokines. Gene expression (adipokines, bone marker genes, MMPs, TIMPs) and cytokine production was evaluated by realtime-polymerase chain reaction (realtime-PCR) and enzyme-linked immunosorbent assay (ELISA). Matrix mineralization was quantified using Alizarin red S staining.nnnRESULTSnμCT showed an osteoporotic phenotype of FF compared to OA bone (reduced trabecular thickness and increased ratio of bone surface vs volume of solid bone). Visfatin and leptin were increased in FF vs OA. Visfatin induced the secretion of IL-6, IL-8, and MCP-1 during osteogenic and adipogenic differentiation. In contrast to resistin and leptin, visfatin increased MMP2 and MMP13 during adipogenesis. In osteogenically differentiated cells, MMPs and TIMPs were reduced by visfatin. Visfatin significantly increased matrix mineralization during osteogenesis, whereas collagen type I expression was reduced.nnnCONCLUSIONnVisfatin-mediated increase of matrix mineralization and reduced collagen type I expression could contribute to bone fragility. Visfatin is involved in impaired bone remodeling at the adipose tissue/bone interface through induction of proinflammatory factors and dysregulated MMP/TIMP balance during MSC differentiation.