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Anti-CD38 monoclonal antibodies have consistently shown increased efficacy when added to standard of care for patients with multiple myeloma. We aimed to assess the efficacy of isatuximab in addition to lenalidomide, bortezomib, and dexamethasone in patients with newly diagnosed transplantation-eligible multiple myeloma.This open-label, multicentre, randomised, active-controlled, phase 3 trial was done at 67 academic and oncology practice centres in Germany. This study is ongoing and divided into two parts; herein, we report results from part 1. Eligible patients were aged 18-70 years; had a confirmed diagnosis of untreated multiple myeloma requiring systemic treatment and a WHO performance status of 0-2; and were eligible for induction therapy, high-dose melphalan and autologous haematopoietic stem-cell transplantation, and maintenance treatment. Patients were randomly assigned (1:1) to receive three 42-day cycles of induction therapy either with isatuximab plus lenalidomide, bortezomib, and dexamethasone (isatuximab group) or lenalidomide, bortezomib, and dexamethasone alone (control group) using a web-based system and permuted blocks. Patients in both groups received lenalidomide (25 mg orally on days 1-14 and 22-35), bortezomib (1·3 mg/mBetween Oct 23, 2018, and Sep 22, 2020, 660 patients were included in the ITT analysis (331 in the isatuximab group and 329 in the control group). 654 (99%) patients were White, two were African, one was Arabic, and three were Asian. 250 (38%) were women and 410 (62%) were men. The median age was 59 years (IQR 54-64). MRD negativity after induction therapy was reached in 166 (50%) patients in the isatuximab group versus 117 (36%) in the control group (OR 1·82 [95% CI 1·33-2·48]; p=0·00017). Median follow-up time from start to end of induction therapy was 125 days (IQR 125-131) versus 125 days (125-132). At least one grade 3 or 4 adverse event occurred in 208 (63%) of 330 patients versus 199 (61%) of 328 patients. Neutropenia of grade 3 or 4 occurred in 77 (23%) versus 23 (7%) patients and infections of grade 3 or 4 occurred in 40 (12%) versus 32 (10%) patients. Among 12 deaths during induction therapy, one death due to septic shock in the isatuximab group and four deaths (one cardiac decompensation, one hepatic and renal failure, one cardiac arrest, and one drug-induced enteritis) in the control group were considered treatment-related.Addition of isatuximab to lenalidomide, bortezomib, and dexamethasone for induction therapy improved rates of MRD negativity with no new safety signals in patients with newly diagnosed transplantation-eligible multiple myeloma.Sanofi and Bristol Myers Squibb (Celgene).

COVID-19 may affect many endocrine tissues as well as thyroid gland and hypothalamus-pituitary-thyroid axis. It has been shown that COV D-19 infection suppresses thyroid hormones in some studies and causes subacute thyroiditis in the others so that its effects are still not fully known. The aim of our study is to retrospectively evaluate thyroid functions, clinical findings, biochemical and inflammatory markers in PCR positive patients infected with COVID-19; and to evaluate the relationship between abnormal thyroid function tests (TFT) and clinical and laboratory findings and whether it has potential prognostic significance.The data of patients aged 18 years and older, 201 patients who applied to Mersin City Training and Research Hospital due to COVID-19 infection between 1st of March and 1st of April in 2021 and received inpatient treatment were evaluated retrospectively.Large TFT (TSH, T3, T4, anti-TPO) and laboratory data of 201 patients with mild, moderate or severe pneumonia on CT were scanned retrospectively. 121 (60.2%) of the patients were male, mean age was 51.9 ± 14.6 years, and the most common comorbid disease was hypertension in 65 (32.3%) patients.It has been determined that the deterioration in TFTs is associated with LDH and D-dimer which are indicators of cell and endothelial damage, duration of hospitalization, clinical severity, and having mutant strains and it has been concluded that low TSH can be used as a prognostic indicator in COVID-19 patients. Further studies with healthy control groups, quantitative RT-PCR tests, histological and pathological correlations, and long-term follow-up are needed.COVID-19 može uticati na mnoga endokrina tkiva, kao i na štitnu žlezdu i osovinu hipotalamus-hipofiza-štitna žlezda. Pokazalo se da infekcija COVID-19 potiskuje hormone štitne žlezde u nekim studijama, a izaziva subakutni tiroiditis u drugim, tako da njeni efekti još uvek nisu u potpunosti poznati. Cilj našeg istraživanja je da se retrospektivno proceni funkcije štitne žlezde, klinički nalazi, biohemijski i inflamatorni markeri kod PCR pozitivnih pacijenata inficiranih COVID-19; i da proceni odnos između abnormalnih testova funkcije štitaste žlezde (TFT) i kliničkih i laboratorijskih nalaza i da li ima potencijalni prognostički značaj.Podaci o 201 pacijenta starijih od 18 godina, koji su se prijavili u bolnicu za obuku i istraživanje u gradu Mersin zbog COVID-19 infekcije između 1. marta i 1. aprila 2021. godine i koji su primili bolničko lečenje, procenjeni su retrospektivno.Retrospektivno su skenirani veliki TFT (TSH, T3, T4, anti-TPO) i laboratorijski podaci 201 pacijenta sa blagom, umerenom ili teškom pneumonijom na CT. 121 (60,2%) obolelih bilo je mu{kog pola, prosečne starosti 51,9 ± 14,6 godina, a načešća komorbidna bolest bila je hipertenzija kod 65 (32,3%) bolesnika.Utvrđeno je da je pogoršanje TFT-a povezano sa LDH i D-dimerom koji su indikatori oštećenja ćelija i endo-tela, trajanja hospitalizacije, kliničke težine i postojanja mutantnih sojeva i zaključeno je da se može koristiti nizak TSH kao prognostički indikator kod pacijenata sa COVID-19. Potrebne su dalje studije sa zdravim kontrolnim grupama, kvantitativni RT-PCR testovi, histološke i patološke korelacije i dugotrajno praćenje.

Introduction: Vitamin D deficiency plays a role also in the occurrence of autoimmune diseases, including heart disease, cancer, inflammatory bowel diseases, diabetes, and rheumatological diseases. In addition, vitamin B12 deficiency, one of the autoimmune diseases, can also be seen in cases of Vitamin D deficiency. Furthermore, Vitamin D is also associated with insulin secretion and increased insulin sensitivity in target cells, and relevant studies reported Vitamin D deficiency at the initial stage of diabetes mellitus (DM). Accordingly, the present study aimed to investigate the relationship between Vitamin D, DM, Vitamin B12, and ferritin in patients presented to the internal medicine outpatient clinic. Materials and Methods: The data from adults aged 18 years and over, who presented to the Internal Medicine Outpatient Clinic of the Mersin City Training and Research Hospital between 01 June 2021 and 31 December 2021 were retrospectively investigated. Results: 476 (95.2%) patients had vitamin D levels below 30 ng/ml, 20 (4.0%) had vitamin B12 levels below 200 pg/ml, and 319 (63.8%) patients had ferritin levels below 20 ng/ml. There was a significant decrease in ferritin in female gender (p

ÖZ Amaç:. Çalışmada hastanemizde yapılan tiroid ultrason sonuçlarının TIRADS şekliyle yorumlanması, tiroid İİAB sonuçlarını, cerrahi uygulanan hastaların histopatolojik bulgularını güncel literatür eşliğinde retrospektif olarak değerlendirmeyi amaçladık. Gereç ve Yöntemler: Mersin Şehir Eğitim ve Araştırma Hastanesinde, 01.01.2020-31.12.2020 tarihleri arasında 869 hastanın yapılan ultrason, ardışık tiroid İİAB işlemleri ve opere olan hastaların patoloji sonuçları retrospektif olarak incelenmiştir. Bulgular: Nodüllerin 691(%79.5) solid, 142 (%16.3) mix ve 36 (%4.1) kistik yapıda olup, 296 (%34.1) hastada tek nodül saptanırken, 572 (%65.8) hastada multiple nodül mevcuttu. Nodül boyutunu küçüldükçe malign olma potansiyelindeki artış (p=0.008) istatiksel olarak anlamlı olarak değerlendirildi. Opere edilen 61(%7) hastanın histopatolojik sonuçları, 32 (%52.4) adet benign, 20 (%32.8) adet papiller karsinom, 8 (%13.1) adet papiller mikrokarsinom, 1(%1.6) adet foliküler neoplazi olarak rapor edildi. Benign sitolojiye sahip 32 (%52.4) olan hastalarda en çok 10(%16.4)’ü Bethesda 3/ TIRADS 4 olarak tespit edildi. En sık tespit edilen papiller karsinoma 20(%32.7) sahip olan hastaların 3 (%4.9) Bethesda 3/TRIADS 4 ;3 (%4.9) Bethesda 3/TRIADS 5 tespit edildi. Sonuç: Çalışmada TIRADS’a göre malign olarak kategorize edilmesine rağmen Bethesda’ya göre benign grup olarak kabul edilen özellikle Bethesda 1-2-3 hastaları, TIRADS ve Bethesda sistemi birlikte değerlendirildiğinde erken dönemde maligniteyi yakalayabildiği gibi, gereksiz cerrahileri azaltılabileceğinin göz önünde tutulması önerilmektedir. Sonuç olarak iki yöntemin birleştirilerek kullanılması desteklenmektedir; tiroid ultrasonu yapan radyologların, klinisyenlerin ve cerrahların ultrason raporlarını ACR-TIRADS ile ilişkilendirmeleri ve sonuçlarını da takip etmeleri tavsiye edilmektedir..

The molecular causes of myeloproliferative neoplasms (MPNs) have not yet been fully elucidated. Approximately 7% to 8% of the patients carry predisposing genetic germline variants that lead to driver mutations, which enhance JAK-STAT signaling. To identify additional predisposing genetic germline variants, we performed whole-exome sequencing in 5 families, each with parent-child or sibling pairs affected by MPNs and carrying the somatic JAK2 V617F mutation. In 4 families, we detected rare germline variants in known tumor predisposition genes of the DNA repair pathway, including the highly penetrant BRCA1 and BRCA2 genes. The identification of an underlying hereditary tumor predisposition is of major relevance for the individual patients as well as for their families in the context of therapeutic options and preventive care. Two patients with essential thrombocythemia or polycythemia vera experienced progression to acute myeloid leukemia, which may suggest a high risk of leukemic transformation in these familial MPNs. Our study demonstrates the relevance of genetic germline diagnostics in elucidating the causes of MPNs and suggests novel therapeutic options (eg, PARP inhibitors) in MPNs. Furthermore, we uncover a broader tumor spectrum upon the detection of a germline mutation in genes of the DNA repair pathway.

Annals of hematology 100(12), 2943-2956 (2021). doi:10.1007/s00277-021-04615-8, Published by Springer, Berlin ; Heidelberg ; New York

COVID-19 disease caused by the novel coronavirus (SARS-CoV-2) results in several manifestations involving the lungs, upper respiratory tract, gastrointestinal tract, and hematological system. During the ongoing COVID-19 pandemic, skin lesions were observed. These lesions resolve rapidly on treatment with corticoid creams and antihistamines. In this report, we present a case of COVID-19 with cutaneous manifestations.

Bu makale, ketiapin doz aşımına bağlı miyokarditi bildirmektedir. Anksiyete bozukluğu nedeniyle 25 mg ketiapin kullanan 18 yaşında kadın hasta, 20 adet ketiapin hapı ile intihar girişiminde bulundu. Acil serviste hastada çarpıntı, nefes darlığı, plöretik göğüs ağrısı ve konfüzyon gelişti. Hastanın EKG'sinde D1-aVL derivasyonlarında ST elevasyonu ve sağ dal bloğu saptandı. Kardiyak belirteçler önemli ölçüde yükseldi. Hasta dahiliye yoğun bakım ünitesinde tedavi altına alındı. İlaca bağlı miyokardit, iki haftalık tedaviyle düzeldi. Bu vaka raporu, ketiapin doz aşımının neden olduğu bir miyokardit vakasını sunmaktadır.

In the past years, high dose chemotherapy (HDT) with autologous stem cell transplantation (ASCT)has more extensively been performed in elderly patients with multiple myeloma (MM). Several studies found a similar survival benefit compared to younger patients. The objective of our retrospective study is to analyse the tolerability of HDT + ASCT in elderly patients.We compared 26 ASCT performed in MM patients ≥65 years to 127 ASCT in patients65 years by evaluating treatment-tolerability, length of hospital stay and number of transfusions.There was no significant difference in the duration of hospitalisation (16 days (range 14-47) in the elderly vs. 17 days (range 14-71) days, P = 0.0903), median time of cytopenia (neutrophils500/μl: 5 days (range 4-24) vs. 6 days (range 3-28) days, P = 0.1091; platelets30 000/μl: 6 days (range 3-36) vs. 7 days (range 0-53) days, P = 0.274) or incidence of, or degree of complications between the two age-groups. Immediate and day 100 treatment related mortality (TRM) was comparable in both groups (3.85% vs. 1.58%, P = 0.4304).our findings support the concept that HDT + ASCT can be safely administered as first-line option for well-selected patients≥65 years.

Annals of hematology 101(12), 2655-2663 (2022). doi:10.1007/s00277-022-05000-9, Published by Springer, Berlin ; Heidelberg ; New York

Classical Philadelphia chromosome-negative myeloproliferative neoplasms (MPN) are a heterogeneous group of hematopoietic malignancies including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). The JAK2V617F mutation plays a central role in these disorders and can be found in 90% of PV and ~50-60% of ET and PMF. Hypoxia-inducible factor 1 (HIF-1) is a master transcriptional regulator of the response to decreased oxygen levels. We demonstrate the impact of pharmacological inhibition and shRNA-mediated knockdown (KD) of HIF-1α in JAK2V617F-positive cells. Inhibition of HIF-1 binding to hypoxia response elements (HREs) with echinomycin, verified by ChIP, impaired growth and survival by inducing apoptosis and cell cycle arrest in Jak2V617F-positive 32D cells, but not Jak2WT controls. Echinomycin selectively abrogated clonogenic growth of JAK2V617F cells and decreased growth, survival, and colony formation of bone marrow and peripheral blood mononuclear cells and iPS cell-derived progenitor cells from JAK2V617F-positive patients, while cells from healthy donors were unaffected. We identified HIF-1 target genes involved in the Warburg effect as a possible underlying mechanism, with increased expression of Pdk1, Glut1, and others. That was underlined by transcriptome analysis of primary patient samples. Collectively, our data show that HIF-1 is a new potential therapeutic target in JAK2V617F-positive MPN.

Calreticulin (CALR) mutations are driver mutations in myeloproliferative neoplasms (MPNs), leading to activation of the thrombopoietin receptor, and causing abnormal megakaryopoiesis. Here, we generated patient-derived CALRins5- or CALRdel52-positive induced pluripotent stem (iPS) cells to establish a MPN disease model for molecular and mechanistic studies. We demonstrated myeloperoxidase deficiency in CD15+ granulocytic cells derived from homozygous CALR-mutant iPS cells, rescued by repairing the mutation using CRISPR/Cas9. iPS cell-derived megakaryocytes showed characteristics of primary megakaryocytes such as formation of demarcation membrane system and cytoplasmic pro-platelets protrusions. Importantly, CALR mutations led to enhanced megakaryopoiesis and accelerated megakaryocytic development in a thrombopoietin-independent manner. Mechanistically, our study identified differentially regulated pathways in mutated vs. unmutated megakaryocytes, such as hypoxia signaling, which represents a potential target for therapeutic intervention. Altogether, we demonstrate key aspects of mutated CALR-driven pathogenesis, dependent on its zygosity and found known and novel therapeutic targets, making our model a valuable tool for clinical drug screening in MPNs.

The therapeutic armamentarium in multiple myeloma has been significantly broadened by proteasome inhibitors, highly efficient means in controlling of multiple myeloma. Despite the developments of therapeutic regimen in treatment of multiple myeloma, still the complete remission requires a novel therapeutic strategy with significant difference in outcomes. Proteasome inhibitors induce autophagy and ER stress, both pivotal pathways for protein homeostasis. Recent studies showed that the IRE1α-XBP1 axis of the unfolded protein response (UPR) is up-regulated in multiple myeloma patients. In addition, XBP1 is crucial for the maintenance of viability of acute lymphoblastic leukemia (ALL).We analyzed the efficacy of targeting IRE1α-XBP1 axis and autophagy in combination with proteasome inhibitor, ixazomib in treatment of multiple myeloma. In this present study, we first show that targeting the IRE1α-XBP1 axis with small molecule inhibitors (STF-083010, A106) together with the ixazomib induces cell cycle arrest with an additive cytotoxic effect in multiple myeloma. Further, we examined the efficacy of autophagy inhibitors (bafilomycin A, BAF and chloroquine, CQ) together with ixazomib in multiple myeloma and observed that this combination treatment synergistically reduced cell viability in multiple myeloma cell lines (viable cells Ixa: 51.8 ± 3.3, Ixa + BAF: 18.3 ± 7.2, Ixa + CQ: 38.4 ± 3.7) and patient-derived multiple myeloma cells (Ixa: 59.6 ± 4.4, Ixa + CQ: 7.0 ± 2.1). We observed, however, that this combined strategy leads to activation of stress-induced c-Jun N-terminal kinase (JNK). Cytotoxicity mediated by combined proteasome and autophagy inhibition was reversed by addition of the specific JNK inhibitor JNK-In-8 (viable cells: Ixa + BAF: 11.6 ± 7.0, Ixa + BAF + JNK-In-8: 30.9 ± 6.1).In this study we showed that combined inhibition of autophagy and the proteasome synergistically induces cell death in multiple myeloma. Hence, we consider the implication of pharmaceutical inhibition of autophagy together with proteasome inhibition and UPR-directed therapy as promising novel in vitro treatment strategy against multiple myeloma.

Summary Calreticulin (CALR) mutations are driver mutations in myeloproliferative neoplasms (MPNs), leading to activation of the thrombopoietin receptor and causing abnormal megakaryopoiesis. Here, we generated patient-derived CALRins5- or CALRdel52-positive induced pluripotent stem cells (iPSCs) to establish an MPN disease model for molecular and mechanistic studies. We demonstrated myeloperoxidase deficiency in granulocytic cells derived from homozygous CALR mutant iPSCs, rescued by repairing the mutation using CRISPR/Cas9. iPSC-derived megakaryocytes showed characteristics of primary megakaryocytes such as formation of demarcation membrane system and cytoplasmic pro-platelet protrusions. Importantly, CALR mutations led to enhanced megakaryopoiesis and accelerated megakaryocytic development in a thrombopoietin-independent manner. Mechanistically, our study identified differentially regulated pathways in mutated versus unmutated megakaryocytes, such as hypoxia signaling, which represents a potential target for therapeutic intervention. Altogether, we demonstrate key aspects of mutated CALR-driven pathogenesis dependent on its zygosity, and found novel therapeutic targets, making our model a valuable tool for clinical drug screening in MPNs., Graphical abstract, Highlights • CALR-mutated iPSCs allow efficient modeling of human MPN disease • CRISPR-mediated repair of CALR mutations rescues normal iPSC function • Megakaryopoiesis in CALR-mutated iPSCs is hyperplastic and accelerated • Transcriptome screen of mutated megakaryocytes identifies novel therapeutic options, In this article, Koschmieder and colleagues establish a novel MPN patient-specific iPSC model to investigate the impact of calreticulin (CALR) frameshift mutations in hematopoiesis. They report hyperplastic and accelerated megakaryopoiesis caused by CALR mutations. RNA sequencing of iPSC-derived megakaryocytes highlights transcriptomic differences between mutated and unmutated megakaryocytes, such as upregulation of hypoxia-related pathways.

Pegylated interferon-α (peg-IFNa) treatment induces molecular responses (MR) in patients with myeloproliferative neoplasms (MPNs), including partial MR (PMR) in 30–40% of patients. Here, we compared the efficacy of IFNa treatment in JAK2V617F- vs. calreticulin (CALR)-mutated cells and investigated the mechanisms of differential response. Retrospective analysis of MPN patients treated with peg-IFNa demonstrated that patients harboring the JAK2V617F mutation were more likely to achieve PMR than those with mutated CALR (p = 0.004), while there was no significant difference in hematological response. In vitro experiments confirmed an upregulation of IFN-stimulated genes in JAK2V617F-positive 32D cells as well as patient samples (peripheral blood mononuclear cells and CD34+ hematopoietic stem cells) compared to their CALR-mutated counterparts, and higher IFNa doses were needed to achieve the same IFNa response in CALR− as in JAK2V617F-mutant 32D cells. Additionally, Janus-activated kinase-1 (JAK1) and signal transducers and activators of transcription 1 (STAT1) showed constitutive phosphorylation in JAK2V617F-mutated but not CALR-mutated cells, indicating priming towards an IFNa response. Moreover, IFN-induced growth arrest was counteracted by selective JAK1 inhibition but enhanced by JAK2 inhibition. In conclusion, our data suggest that, clinically, higher doses of IFNa are needed in CALR-mutated vs. JAK2V617F-positive patients and we suggest a model of JAK2V617F-JAK1/STAT1 crosstalk leading to a priming of JAK2V617F-positive cells to IFNa resulting in differential sensitivity.

Background: In newly-diagnosed multiple myeloma (NDMM), lenalidomide/bortezomib/dexamethasone (RVd) is one of the most widely used combination regimens. Anti-CD38 monoclonal antibodies (CD38-moAb) increase efficacy when added to standard-of-care regimens. Here we present the first primary endpoint of the randomized, open-label, multicenter, phase III GMMG-HD7 trial, comparing RVd without (arm IA) or with the CD38-moAb isatuximab (Isa, arm IB) with regard to the rate of minimal residual disease (MRD) negativity after induction therapy in patients with transplant-eligible NDMM. Patients and Methods: Patients with transplant-eligible NDMM at 67 sites in Germany were equally randomized to receive three 42-day cycles of RVd (lenalidomide 25 mg/d p.o., d1-14 and d22-35; bortezomib 1.3 mg/m 2 s.c. d1, 4, 8, 11, 22, 25, 29, 32; dexamethasone 20 mg/d d1-2, 4-5, 8-9, 11-12, 15, 22-23, 25-26, 29-30, 32-33) in both arms. Isa was added to arm IB only (10 mg/kg i.v., cycle 1: d 1, 8, 15, 22, 29; cycles 2-3: d 1, 15, 29). Randomization for induction was stratified according to revised International Staging System (R-ISS). Primary endpoint of the trial was MRD negativity assessed by next-generation flow (NGF, cut off 1x10 -5) after induction. Secondary endpoints included rates of complete response (CR) after induction and safety. Data cut-off for the present analysis was April 2021. Results: Between 10/2018 and 09/2020, 662 patients were included in the trial. 660 patients were eligible for intention-to-treat analysis and 658 patients started induction (RVd: 329/328 and Isa-RVd: 331/330). Median age was 58 (range 26-70) years and baseline characteristics were well balanced between treatment arms. On induction, 35 (10.6%) and 18 (5.4%) patients discontinued treatment in the RVd vs. Isa-RVd arms (p=0.02). Among these, 8 (2.4%, RVd) vs. 7 (2.1%, Isa-RVd) patients discontinued induction due to adverse events (AE). 293 (89.1%) vs. 312 (94.3%) patients in the RVd vs. Isa-RVd arms continued further study treatment after induction. MRD negativity rates after induction were 35.6% vs. 50.1% (odds ratio [OR]=1.83, 95% confidence interval [95% CI]: 1.34-2.51, p At least one AE (grade ≥3) on induction occurred in 61.3% (RVd) and 63.6% (Isa-RVd) of patients (p=0.57). Most common AE (grade ≥3) by system organ class (SOC) for RVd vs. Isa-RVd were: "investigations": 23.5% vs. 23.9% (p=0.93), "blood and lymphatic system disorders": 16.8% vs. 25.8% (p=0.006), "infections and infestations": 10.4% vs. 13.0% (p=0.33) and "nervous system disorders": 10.1% vs. 8.5% (p=0.50). Rates of serious AE (SAE, any grade) on induction were similar between RVd and Isa-RVd (36.3% vs. 34.8%, p=0.75). Eight (RVd) and four (Isa-RVd) patients died during induction. Conclusions: The GMMG-HD7 trial met its primary endpoint. To the best of our knowledge this is the first phase III trial to demonstrate superiority of MRD negativity rates after induction by adding a CD38-moAb to RVd. There were no increased rates of SAE or early discontinuation in patients treated with Isa-RVd compared to RVd. The trial is ongoing, including analyses post autologous transplantation, which is followed by a second randomization to compare the efficacy of the addition of Isa to lenalidomide maintenance. Disclosures Goldschmidt: Takeda: Consultancy, Research Funding; Sanofi: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Adaptive Biotechnology: Consultancy; Incyte: Research Funding; GSK: Honoraria; Chugai: Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Celgene: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; BMS: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Janssen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Johns Hopkins University: Other: Grant; Molecular Partners: Research Funding; MSD: Research Funding; Mundipharma: Research Funding; Dietmar-Hopp-Foundation: Other: Grant; Novartis: Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding. Mai: Celgene / BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding; Glaxo Smith Kline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding. Fenk: Takeda: Honoraria; GSK: Honoraria; Amgen: Honoraria; Janssen: Honoraria; BMS/Celgene: Honoraria. Besemer: Takeda: Honoraria; Janssen: Honoraria; GSK: Honoraria. Dürig: Janssen: Membership on an entity's Board of Directors or advisory committees, Other: Travel Support, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Other: Travel Support, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees. Schroers: BMS/Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; GSK: Consultancy, Honoraria; Takeda: Honoraria. Metzler: Takeda: Consultancy; BMS: Consultancy; GSK: Consultancy; Amgen: Consultancy; Janssen: Consultancy; AstraZeneca: Consultancy; Pfizer: Consultancy; Sanofi: Consultancy. Haenel: Takeda: Consultancy, Honoraria; Jazz: Consultancy, Honoraria; GSK: Consultancy; Bayer Vital: Honoraria; Roche: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Amgen: Consultancy; Celgene: Consultancy, Honoraria. Mann: Cellgene: Consultancy. Asemissen: GSK: Honoraria; Pfizer: Honoraria; Celgene BMS: Honoraria. Heilmeier: Sanofi-Aventis Dtld. GmbH: Consultancy. Kriegsmann: Sanofi: Honoraria. Weinhold: Sanofi: Honoraria. Holderried: Amgen: Speakers Bureau; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees; Eurocept Pharmaceuticals: Other: Travel support; MSD: Speakers Bureau; Gilead Sciences: Consultancy, Membership on an entity's Board of Directors or advisory committees; Abbvie: Other: Travel support; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Other: Travel support; Therakos: Other: Travel support; Daiichi Sankyo: Other: travel support; Medac: Other: Travel support; Jazz Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees. Trautmann-Grill: Sanofi: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; GSK: Consultancy, Honoraria. Gezer: Amgen: Consultancy, Other: Invited Speaker; Takeda: Consultancy, Other: Invited Speaker; BMS: Consultancy, Other: Invited Speaker; Celgene: Consultancy, Other: Invited Speaker. Khandanpour: GSK: Honoraria; Takeda: Honoraria; Janssen: Honoraria; AstraZeneca: Honoraria, Research Funding; Pfizer: Honoraria; Sanofi: Honoraria, Research Funding; BMS/Celgene: Honoraria. Knauf: Amgen: Honoraria; Abbvie: Honoraria; Beigene: Consultancy, Honoraria; BMS: Honoraria; Celgene: Honoraria; Janssen: Consultancy, Honoraria; Sanofi: Honoraria; AstraZeneca: Consultancy, Honoraria. Munder: GSK: Consultancy; Amgen: Honoraria; Sanofi: Consultancy; Takeda: Consultancy, Honoraria; Abbvie: Consultancy; BMS: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Incyte: Research Funding. Hoffmann: Sanofi-Aventis: Consultancy. Raab: Roche: Consultancy; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Honoraria; Janssen: Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees. Salwender: GlaxoSmithKline: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Sanofi: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Chugai: Honoraria; Oncopeptides: Honoraria; Takeda: Honoraria; Amgen: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; AbbVie: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Janssen-Cilag: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Bristol-Myers Squibb/Celgene: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Pfizer: Honoraria. Weisel: Adaptive Biotechnologies: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy; Novartis: Honoraria; Pfizer: Honoraria. OffLabel Disclosure: Isatuximab prior to ASCT in NDMM

Increased energy requirement and metabolic reprogramming are hallmarks of cancer cells. We show that metabolic alterations in hematopoietic cells are fundamental to the pathogenesis of mutant JAK2-driven myeloproliferative neoplasms (MPNs). We found that expression of mutant JAK2 augmented and subverted metabolic activity of MPN cells, resulting in systemic metabolic changes in vivo, including hypoglycemia, adipose tissue atrophy, and early mortality. Hypoglycemia in MPN mouse models correlated with hyperactive erythropoiesis and was due to a combination of elevated glycolysis and increased oxidative phosphorylation. Modulating nutrient supply through high-fat diet improved survival, whereas high-glucose diet augmented the MPN phenotype. Transcriptomic and metabolomic analyses identified numerous metabolic nodes in JAK2-mutant hematopoietic stem and progenitor cells that were altered in comparison with wild-type controls. We studied the consequences of elevated levels of Pfkfb3, a key regulatory enzyme of glycolysis, and found that pharmacological inhibition of Pfkfb3 with the small molecule 3PO reversed hypoglycemia and reduced hematopoietic manifestations of MPNs. These effects were additive with the JAK1/2 inhibitor ruxolitinib in vivo and in vitro. Inhibition of glycolysis by 3PO altered the redox homeostasis, leading to accumulation of reactive oxygen species and augmented apoptosis rate. Our findings reveal the contribution of metabolic alterations to the pathogenesis of MPNs and suggest that metabolic dependencies of mutant cells represent vulnerabilities that can be targeted for treating MPNs.

Philadelphia negative (Ph-neg) myeloproliferative neoplasms (MPN) are a heterogenous group of clonal stem cell disorders. Approved treatment options include hydroxyurea, anagrelide, and ruxolitinib, which are not curative. The concept of synthetic lethality may become an additional therapeutic strategy in these diseases. In our study, we show that DNA repair is altered in classical Ph-neg MPN, as analyzed by gene expression analysis of 11 genes involved in the homologous recombination repair pathway (HRR), the non-homologous end-joining pathway (NHEJ), and the single-strand break repair pathway (SSB). Altogether, peripheral blood-derived cells from 57 patients with classical Ph-neg MPN and 13 healthy controls were analyzed. LIG3 as an essential part of the SSB was significantly lower expressed compared to controls in all three entities (essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF)). In addition, while genes of other DNA-repair pathways showed-possibly compensatory-increased expression in ET (HRR, NHEJ) and PV (NHEJ), MF samples displayed downregulation of all genes involved in NHEJ. With regard to the JAK2 mutational status (analyzed in ET and MF only), no upregulation of the HRR was detected. Though further studies are needed, based on these findings, we conclude that synthetic lethality may become a promising strategy in treating patients with Ph-neg MPN.

Molecular carcinogenesis 59(1), 87-103 (2020). doi:10.1002/mc.23131, Published by Wiley Interscience, New York, NY

Bosutinib is one of the five tyrosine kinase inhibitors which are currently approved for the treatment of chronic myeloid leukemia. By its dual inhibition of Src and ABL kinase and also targeting further kinases, it creates a unique target portfolio which also explains its unique side effect profile. The approval of bosutinib in 2013 made the drug available for patients previously treated with one or more tyrosine kinase inhibitor(s) and for whom imatinib, nilotinib, and dasatinib are not considered appropriate treatment options. As initially the first-line clinical trial comparing bosutinib with imatinib in CML patients in chronic phase did not reach its primary endpoint and therefore the product was not licensed for first-line therapy, a second first-line trial, the so-called BFORE study, was performed and just recently the promising results have been published predicting a quick expansion of the existing label. In comparison with the other approved TKIs, bosutinib harbors a distinct side effect profile with only very few cardiovascular and thromboembolic events and minimal long-term safety issues with most adverse events happening during the first months of treatment. On the other hand, gastrointestinal side effects are very common (e.g., diarrhea rates in more than 80% of the patients) with bosutinib surprising some of the investigators during the early clinical trials evaluating bosutinib. Until then, several approaches have been used to face this problem resulting in extensive supportive efforts (such as early loperamid treatment) as well as new trials testing alternative dosing strategies with early dose adjustment schedules. This article reports preclinical and clinical data available for bosutinib both in hematologic diseases such as CML or ALL and solid tumours as well as other diseases and envisions future perspectives including additional patient groups in which bosutinib might be of clinical benefit.

Macrophages are key mediators of the therapeutic effects exerted by monoclonal antibodies, such as the anti-CD38 antibody MOR202, currently introduced in multiple myeloma (MM) therapy. Therefore, it is important to understand how antibody-mediated effector functions of myeloma-associated macrophages (MAMs) are regulated. Here, we focused on the effects of vitamin D, a known regulator of macrophage effector functions. Consequently, it was the aim of this study to assess whether modulation of the vitamin D pathway alters the tumoricidal activity of MAMs. Here, we demonstrate that MAMs display a defective vitamin D pathway with reduced expression level of CYP27B1 and limited tumoricidal activity which can be restored by the IMiD lenalidomide in vitro. Furthermore, our data indicate that the vitamin D pathway of MAMs from MM patients does recover during an IMiD-containing therapy shown by an improved MOR202-mediated cytotoxic activity of these MAMs against primary MM cells ex vivo. Here, the ex vivo cytotoxic activity could be further enhanced by vitamin D supplementation. These data suggest that vitamin D holds a key role for the effector functions of MAMs and that vitamin D supplementation in IMiD combination trials could further increase the therapeutic efficacy of anti-CD38 antibodies such as MOR202, which remains to be investigated in clinical studies.

Activated carbons were prepared from chestnut shell by phosphoric acid activation and the prepared activated carbons were used to remove lead(II) from aqueous solutions. The effects of impregnation ratio (IR) and activation temperature on activated carbon production were investigated. The produced activated carbons were characterized by N2 adsorption, scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. The highest surface area (1611 m2/g) and total pore volume (0.7819 cm3/g) were obtained at a carbonization temperature of 500°C with an impregnation ratio of 3/1. The resulting activated carbon was used for removal of lead(II) from aqueous solution. The effects of temperature, contact time, and adsorbent dosage were investigated. The adsorption isotherm studies were carried out and the obtained data were analyzed by the Langmuir, Freundlich, and Temkin equations. The rate of adsorption was found to conform to the pseudo-second-order kinetic model. The Langmuir isotherm equation...

Introduction: Interferon alpha (IFNa) is a cytokine with anti-viral and anti-tumoral properties which, either in its unmodified or pegylated form, is successfully used in the treatment of patients with myeloproliferative neoplasms (MPN), including polycythemia (PV), essential thrombocythemia (ET) and early primary myelofibrosis (PMF). Despite its efficacy including molecular responses and thus its potential disease modifying capabilities, IFNa carries the risk of significant adverse events, including liver toxicity, autoimmunity, and depression. This has prompted the development of interferons with improved features including better tolerability. However, biomarkers for response have been lacking, mostly due to the heterogeneity of cells analyzed and the difficulty in obtaining them from the bone marrow. Methods: Therefore, we have set up a clonogenic assay from Ficoll-isolated mononuclear cells of the peripheral blood of patients (PBMC) with MPN (n=51, including 17 PV, 14 ET, and 14 PMF, 1 MDS/MPN, 2 Post-PV-MF, 2 Post-ET-MF, 1 MPNu) to analyze the in vitro IFNa response (either using 0.5 µg/ml ropeginterferon alfa-2b [ropegIFNa] or 500 U/ml recombinant human IFN-alpha2b [hIFNa] or no treatment control) in the cells that drive malignant clonogenic growth in the patients. After 10-14 days, the number of colonies was assessed. For each patient and condition, twenty-five of the resulting colonies were then genotyped for zygosity of JAK2V617F and three colonies per condition were analyzed for STAT1 RNA expression using RT-qPCR, an important transcriptionally induced IFNa target gene. The number of mutated alleles was determined (zero for wildtype, one for heterozygous, two for homozygous colonies), and, based upon the change in mutant alleles after in vitro hIFNa treatment, samples were categorized into responders (mutant alleles decreased) and non-responders (mutant alleles unchanged or increased). All patients provided written informed consent, and the study was approved by the local ethics committee. Results: To assess potential differences between the two interferons used, a 14-day proliferation assay was performed in Set-2 cells, showing more sustained inhibition of proliferation by ropegIFNa than hIFNa (p=0.007), confirming the longer half-life of ropegIFNa. In the clonogenic assay, different colonies were observed depending on the MPN subtype, ranging from exclusive CFU-E (PV) to exclusive CFU-G and CFU-M (PMF) types of colonies. Both hIFNa and ropegIFNa significantly inhibited colony growth as compared to the control and reduced the colony number to 72.7 % (hIFNa) and 58.5% (ropegIFNa) of the untreated control, with ropegIFNa showing significantly stronger effects than hIFNa (p=0.0137). Interestingly, there were marked differences in the amount of JAK2 alleles in the colonies between the patients (n=24 analyzed), with 16 patients showing a reduction of up to 22% of the allele burden upon in vitro treatment with hIFNa (responders), while 8 patients showed no reduction or even an increase of up to 15% (non-responders) (p=0.0001). Basal STAT1 expression in the colonies (three colonies per patient and treatment) was significantly lower in responders than non-responders (p=0.0200). After treatment with hIFNa, STAT1 expression was induced to similar levels in both responders and non-responders (p=0.6620). As a result, STAT1 fold induction was significantly higher in responders than non-responders (p=0.0013). Interestingly, there was no correlation of the responses with current clinical treatment of the patients (previous interferon exposure did not prevent responses) or with the MPN subtype, confirming clinical reports that patients with myelofibrosis can respond to interferon. Conclusion: In conclusion, clonogenic cells from the peripheral blood of MPN patients can be used to assess their molecular response to IFNa. In vitro, ropegIFNa induced stronger effects than non-pegylated IFNa. The responses were heterogeneous at the molecular level, but, when combined with RNA expression analysis, we were able to dissect molecular responders from non-responders. The mechanisms for these differences and their clinical impact are currently being studied. Disclosures Gezer: AMGEM: Membership on an entity's Board of Directors or advisory committees. Isfort:Mundipharma: Other: Travel reimbursement; Amgen: Other: Travel reimbursement; Hexal: Other: Travel reimbursement; BMS: Honoraria; Ariad: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria, Other: Travel reimbursement; Novartis: Consultancy, Honoraria, Other: Travel reimbursement; Roche: Other: Travel reimbursement; Alexion: Other: Travel reimbursement. Brümmendorf:Ariad: Consultancy; Janssen: Consultancy; Pfizer: Consultancy, Research Funding; University Hospital of the RWTH Aachen: Employment; Novartis: Consultancy, Research Funding; Merck: Consultancy. Koschmieder:Ariad: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis Foundation: Research Funding; Bayer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Shire: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AOP Pharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers-Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; CTI: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.

Guitart et al. performed an in vivo genetic dissection of the Krebs cycle enzyme fumarate hydratase (Fh1) in the hematopoietic system. Their investigations revealed multifaceted functions of Fh1 in the regulation of hematopoietic stem cell biology and leukemic transformation., Strict regulation of stem cell metabolism is essential for tissue functions and tumor suppression. In this study, we investigated the role of fumarate hydratase (Fh1), a key component of the mitochondrial tricarboxylic acid (TCA) cycle and cytosolic fumarate metabolism, in normal and leukemic hematopoiesis. Hematopoiesis-specific Fh1 deletion (resulting in endogenous fumarate accumulation and a genetic TCA cycle block reflected by decreased maximal mitochondrial respiration) caused lethal fetal liver hematopoietic defects and hematopoietic stem cell (HSC) failure. Reexpression of extramitochondrial Fh1 (which normalized fumarate levels but not maximal mitochondrial respiration) rescued these phenotypes, indicating the causal role of cellular fumarate accumulation. However, HSCs lacking mitochondrial Fh1 (which had normal fumarate levels but defective maximal mitochondrial respiration) failed to self-renew and displayed lymphoid differentiation defects. In contrast, leukemia-initiating cells lacking mitochondrial Fh1 efficiently propagated Meis1/Hoxa9-driven leukemia. Thus, we identify novel roles for fumarate metabolism in HSC maintenance and hematopoietic differentiation and reveal a differential requirement for mitochondrial Fh1 in normal hematopoiesis and leukemia propagation.

Background and Design: Allergic reactions to Hymenoptera venoms are significant health problems because of their serious outcomes. The aim of this study was to investigate the sensitization rates of Hymenoptera venoms in Mersin region, which are indirect measures of Hymenoptera venom allergy.Material and Method: By using questionnaires, total IgE determination with nephelometric method and phadiotop determinations with fluoroimmunoassay, we performed epidermal/intradermal testing with Apidae, Vespidae and Polistes venom extracts, to determine the sensitization rates among 209 volunteers (86 males, 123 females) with a mean age of 38.4 years. Sensitization rate to venoms of all three species were 21.0% among 209 subjects. Sensitization rate to more than one species simultaneously, was 52.3% among Hymenoptera sensitive subjects. With the aid of questionnanires we found that sting reactions were “normal reactions” in 80%, “large local reactions” in 11.0% and “systemic reactions” in 9% of the subjects. The rate of positive skin tests was 23.5% among the subjects who had described large local reactions and 21.5% among the subjects who had described systemic reactions. There were no significant difference between the sensitization rates of males and famales; of the stratified age groups of subjects; of the subjects with elevated and normal total IgE values; of the subjects with positive and negative phadiotop determinations; of the subjects living in urban and suburban areas; of the subjects with respect to sting number or time elapsed since the last sting or the varieties of sting reactions.Results: The sensitization rates to hymenoptera venoms are significantly elevated, although low in titer, in Mersin region. So, Hymenoptera venom allergy may contribute to health problems, significantly in this part of the country.

Introduction: Ph-negative myeloproliferative neoplasms (MPN) represent a heterogeneous group of hematological malignancies which differ in various aspects such as clinical manifestation, underlying genetic aberrations, cytomorphological features and life expectancy. However, across all subtypes, patients (pts) with MPN often suffer from severe symptoms, resulting in an impairment of the quality of life (QoL). Methods: The German Study Group for MPN (GSG-MPN) Bioregistry is a non-interventional prospective study including pts of at least 18 years with diagnosis of Ph-negative MPN according to WHO criteria (2008) having provided written informed consent. The Bioregistry study also includes assessment of QoL at baseline and on an annual basis, with all pts completing the standardized MPN-SAF-TSS questionnaire (German version) and an additional item indicating pts' subjective overall QoL on an 11-point Likert scale. Total scores range from 0 to 90 and were calculated if at least 6 items were answered (Emanuel RM et al., J Clin Oncol. 2012; 30 (33): 4098-103.)). Clinical variables, as documented in the registry, included comorbidities, reported symptoms as assessed by the physician, bleeding, and thromboembolic events (TEE). For statistical analysis, standard descriptive methods, Spearman correlation coefficient, Wilcoxon test/Kruskal-Wallis test for significance testing, and Kendall´s tau-b statistics were used. Results: 1,403 pts who had completed at least six items of the QoL assessment at baseline were included in this analysis. Median age at diagnosis was 58 years (interquartile range [IQR] 22), 98% were Caucasian, 50% were female. 494 pts were diagnosed with essential thrombocythemia (ET, 35%), 444 pts with polycythemia vera (PV, 32%), 302 pts with primary myelofibrosis (PMF, 22%), 83 pts with MPN-unclassifiable (MPNu, 6%), 43 pts with post-ET-myelofibrosis (pET-MF, 3%) and 37 pts with post-PV-myelofibrosis (pPV-MF, 3%). The most common complaint reported via the MPN-SAF-TSS was fatigue, occurring in more than 80% of the pts in all entities except MPNu (77%). More than 50 % of pts in each entity reported to suffer from early satiety, night sweats, concentration problems, or overall impairment of QoL. Table 1 summarizes all 9 symptoms and overall QoL from the questionnaire categorized by entity. Interestingly, the pts suffering from PET-MF reported the highest symptom burden, while PPV-MF pts showed the lowest overall symptom burden (median total QoL score of 23 vs. 16; p=0.01). The strongest correlations among the different symptoms were seen for fatigue and overall QoL (Spearman´s rho 0.57, p=6 points. The most concordant symptom was night sweats (further details in table 2). Conclusions: Most MPN pts suffer from a significant symptom burden which impairs their QoL. TEE influence fatigue and concentration problems. The perception of symptoms (particularly with respect to fatigue) differs between pts and treating physician which suggests that questionnaires should be used on a routine basis in order to faithfully reflect patient´s degree of suffering from MPN and/or treatment. Disclosures Isfort: Amgen: Other: i.e. travel support; Mundipharma: Other: i.e. travel support; Roche: Other: i.e. travel support; Incyte/Ariad: Consultancy; Pfizer: Consultancy, Honoraria, Other: i.e. travel support; BMS: Honoraria; Novartis: Consultancy, Honoraria, Other: i.e. travel support; Alexion: Other: i.e. travel support; Hexal: Other: i.e. travel support. Stegelmann:Novartis: Consultancy, Honoraria. Al-Ali:Gilead: Consultancy, Research Funding; Otsuka: Consultancy, Honoraria; Alexion: Honoraria; Novartis: Consultancy, Honoraria, Other: Travel support, Research Funding; Celgene: Honoraria, Other: Travel support, Research Funding. Goethert:BMS: Consultancy, Honoraria, Other: i.e. travel support; Incyte: Consultancy, Honoraria, Other: i.e. travel support; Pfizer: Consultancy, Honoraria; Novartis: Honoraria; Proteros Biostructures: Honoraria; AOP Orphan: Other: i.e. travel support. Haenel:Novartis: Honoraria; Takeda: Honoraria; Roche: Honoraria; Amgen: Honoraria. Platzbecker:Celgene: Research Funding. Griesshammer:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Brümmendorf:Pfizer: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy; Takeda: Consultancy.

Hypereosinophilia (HE) is caused by a variety of disorders, ranging from parasite infections to autoimmune diseases and cancer. Massive overproduction of hyperactive eosinophils leads to enhanced tissue infiltration and, in some cases, severe organ damage. Clonal malignancies with HE involve the FIP1L1-PDGFRA (F/P)-positive neoplasms and other neoplasms harboring PDGFRA and PDGFRB rearrangements, all of which are sensitive to imatinib. However, most subtypes do not carry a defined genetic aberration and, therefore, lack specific treatment. In eosinophils, modulation of the actin cytoskeleton is mandatory for priming and migratory function. In this study, we aimed to target the actin-binding protein LCP1, also termed L-plastin, to reduce eosinophilic burden in HE. LCP1 is a direct target of the serine/threonine kinase PKCß, which phosphorylates LCP1 at serine 5, essential for its full activity. We confirmed high LCP1 expression and Ser5 phosphorylation dependent on F/P activity in the HES cell line Eol-1 and 32D-F/P cells. The PKCβ selective inhibitor enzastaurin led to dephosphorylation of LCP1 in Eol-1 cells, and this was associated with significantly reduced proliferation (p < 0.0001), metabolic activity (p < 0.0001), and colony formation (11.8 fold reduced) as well as enhanced apoptosis (p < 0.0001) and impaired migration to SDF-1 (p < 0.001). Apoptosis was associated with ß-Catenin and c-Jun protein stabilization and increased expression of p73. Reduced surface expression of CD11b was detected (1.5 fold reduction; p=0.0043), which may explain the impaired migration capacity to SDF-1. While enzastaurin did not alter F/P-induced STAT3, STAT5, and ERK1/2 phosphorylation, it specifically inhibited STAT1Tyr701 and AKTSer473 but not AKTThr308 phosphorylation, and shRNA knock-down experiments confirmed that this process was mediated by LCP1. The mTORC2 complex triggers AKTSer473 phosphorylation, and PDK1 is the main Ser/Thr kinase responsible for AKTThr308 phosphorylation. Knockdown of LCP1 protein or reduction of its phosphorylation by enzastaurin treatment resulted in mTORC2 activity loss, while PDK1 activity remained unchanged, suggesting differential phosphorylation of AKTSer473 and AKTThr308. Importantly, AKT substrate activity was significantly reduced upon loss ofAKTSer473 phosphorylation, and SIN1T86 phosphorylation as an indicator of mTORC2 activity was dependent on LCP1 protein, suggesting that targeting of LCP1 reduces mTORC2 activity. Biologically, both enzastaurin treatment and LCP1 knockdown led to impaired IL5-induced eosinophil differentiation of HoxB8-immortalized murine bone marrow progenitor cells (10.1 fold decrease; p=0.021). Moreover, enzastaurin reduced eosinophil differentiation (1.38 fold decrease; p=0.005) and survival (1.6 fold decrease; p=0.0078) of primary peripheral blood-derived samples from HE patients in vitro. In conclusion, our data demonstrate that HE involves active LCP1, which triggers mTORC2 activity and eosinophil migration, and that the PKCβ inhibitor enzastaurin may provide a novel treatment approach for hypereosinophilic disorders. Disclosures Reiter: Incyte: Consultancy, Honoraria. Brümmendorf:Takeda: Consultancy; Pfizer: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Merck: Consultancy; Janssen: Consultancy.

Myeloproliferative neoplasms (MPN) are a heterogeneous group of malignancies including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The JAK2V617F mutation can be found in 90% of PV and approximately 50% of ET and PMF patients. Hypoxia-inducible factors (HIFs) are master transcriptional regulators of the response to decreases in cellular oxygen levels. Unveiling the function of deregulated HIF-1 signaling in normal and malignant hematopoiesis was the aim of several recent publications, highlighting the importance of HIF-1 for the maintenance of leukemic stem cells (LSCs) in acute and chronic myeloid leukemia (AML/CML). In a JAK2V617F knock-in mouse model and in patients, JAK2V617F was shown to induce the accumulation of reactive oxygen species (ROS) in the hematopoietic stem cell compartment, leading to a stabilization of HIF-1α protein. Further, aberrant STAT5 and PI3K/AKT/mTOR signaling induced HIF-1α expression on the transcriptional and translational level. Ruxolitinib treatment inhibited growth and reduced the expression of HIF-1α and its target gene VEGF in the JAK2V617F human erythroleukemia cell line HEL. In several leukemic cell lines constitutive expression of HIF-1α was reported, even under normoxic conditions. However, it still remains unknown whether HIF-1α plays a role in JAK2V617F positive MPN. In this study, we investigated the role HIF-1α signaling in JAK2V617F positive MPN in vitro. We retrovirally transduced the murine bone marrow cell line 32D with JAK2V617F or JAK2WT. Western blot analysis revealed significant increases in HIF-1α protein levels in JAK2V617F positive cells compared to JAK2WT controls after cultivation in normoxic conditions and this effect was abrogated by treatment with the JAK1/JAK2 inhibitor ruxolitinib. Inhibition of HIF-1, binding to hypoxia response elements (HRE), by low doses of echinomycin (1 nM), significantly impaired proliferation and survival. Using an Annexin-V/7-AAD flow cytometry assay apoptosis was found to be selectively induced in JAK2V617F positive, but not JAK2WT cells after echinomycin treatment. Additionally, BrdU/7-AAD cell cycle analysis revealed that only JAK2V617F positive cells were significantly arrested in G0/1 phase. These findings were consistent with shRNA-mediated knockdown (KD) of HIF-1α in JAK2V617F transduced 32D cells in presence but not the absence of HIF-2 antagonist 2. Inhibition of HIF-2 was necessary due to a compensatory increase of HIF-2α protein levels, shown by Western Blot analysis, counteracting HIF-1α-KD mediated effects. We isolated PBMCs and BMMNCs from JAK2V617F positive patients or healthy controls using Ficoll density gradient centrifugation. Echinomycin significantly abrogated the colony formation ability alone and in combination with ruxolitinib. In vitro treatment with echinomycin significantly decreased cell number and viability of 8 JAK2V617F positive BMMNC samples (4 PV, 3 PMF, 1 preMF; p[1nM]=0.0169, p[5nM]=0.0009) and 7 PBMC samples (6 PV, 1 PMF; p[1nM]=0.0156, p[5nM]=0.0156) in a dose-dependent manner. In contrast, PBMCs from 6 healthy donors were unaffected by the treatment. The same effect was observed in heterozygous and homozygous iPS cell-derived progenitors from JAK2V617F positive PV patients, whereas JAK2WT cells were unaffected by the treatment. Collectively, our data indicate that targeting HIF-1 might represent a novel therapeutic approach in classical Philadelphia-chromosome-negative MPN. Disclosures Brümmendorf: Pfizer: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy; Takeda: Consultancy.

We analysed the clinical impact of epigenetic dysregulation of the Wnt pathway in malignant plasma cell disorders. In multiple myeloma (MM) cell lines, aberrant promoter hypermethylation of the secreted Frizzled-related protein (SFRP) genes was a common event, and hypermethylation of SFRP1,-2 and -5 was associated with transcriptional silencing. Among 76 primary patient samples, the frequency of aberrant methylation was 35.5% for SFRP1, 52.6% for SFRP2, 1.3% for SFRP4 and 6.9% for SFRP5. Hypermethylation of SFRP1 and -2 genes was detected in monoclonal gammopathy of undetermined significance and all MM stages including plasma cell leukaemia (PCL), while SFRP5 methylation was restricted to advanced MM stages and PCL. Our data indicate that epigenetic silencing of Wnt antagonists is an early event in MM pathogenesis and that SFRP5 hypermethylation may play a role in disease progression.

Leukemogenesis occurs under hypoxic conditions within the bone marrow (BM). Knockdown of key mediators of cellular responses to hypoxia with shRNA, namely hypoxia-inducible factor-1α (HIF-1α) or HIF-2α, in human acute myeloid leukemia (AML) samples results in their apoptosis and inability to engraft, implicating HIF-1α or HIF-2α as therapeutic targets. However, genetic deletion of Hif-1α has no effect on mouse AML maintenance and may accelerate disease development. Here, we report the impact of conditional genetic deletion of Hif-2α or both Hif-1α and Hif-2α at different stages of leukemogenesis in mice. Deletion of Hif-2α accelerates development of leukemic stem cells (LSCs) and shortens AML latency initiated by Mll-AF9 and its downstream effectors Meis1 and Hoxa9. Notably, the accelerated initiation of AML caused by Hif-2α deletion is further potentiated by Hif-1α codeletion. However, established LSCs lacking Hif-2α or both Hif-1α and Hif-2α propagate AML with the same latency as wild-type LSCs. Furthermore, pharmacological inhibition of the HIF pathway or HIF-2α knockout using the lentiviral CRISPR-Cas9 system in human established leukemic cells with MLL-AF9 translocation have no impact on their functions. We therefore conclude that although Hif-1α and Hif-2α synergize to suppress the development of AML, they are not required for LSC maintenance.

In addition to antimicrobial activity, macrophages regulate tissue development, remodeling, and repair. In terms of neoplastic growth, tumor-associated macrophages (TAMs) are even considered pro-tumorigenic based on their angiogenic and T-cell suppressive properties. In multiple myeloma (MM) macrophages represent an abundant component of the stromal cell compartment and are believed to support proliferation, survival, and drug resistance of MM cells. Those pro-tumorigenic functions are partly instructed by T-helper (TH)-2 cytokines such as interleukin-4 (IL-4) and IL-10, which skew TAM differentiation towards an alternatively activated, or so-called M2-like, phenotype. In contrast, M1 macrophages generally considered as potent effectors in response to microbial products or interferon-γ (IFN-γ), are characterized by superior antigen-presentation, abundant production of pro-inflammatory cytokines such as interleukin-12 (IL-12), and consequently, promote a polarized type I immune response against infections as well as malignant cells. Transcriptional regulation is a key determinant for macrophage polarization. The Ikaros (IKZF1) transcription factor is critical for lymphoid development and is found in all hematopoietic progenitors as well as in T-, B-, NK-cells and macrophages. Interestingly, IKZF1 is overexpressed in MM and selectively degraded by lenalidomide, which is approved in MM therapy. The potential role of IKZF1 in modulating macrophage polarization has not been elucidated yet. Here, we show that IKZF1expression is found highly elevated in M2-like macrophages and in MM TAMs. IKZF1 deletion in human macrophages by small interfering RNA (siRNA) or by lenalidomide yields an upregulation of M1-specific cytokines (IL-12 and IL-1b), chemokines (CXCL10 and CCL5), and costimulatory molecules (CD86 and CD40) and leads to a potent TH1-TH17 response. In fact, lenalidomide-pretreated macrophages display strong tumoricidal effects when co-cultured with MM cell lines as opposed to their untreated counterparts promoting MM proliferation and viability. Utilizing immunoprecipitation-sequencing (ChIP-Seq) we reveal that IKZF1 governs IRF4 and IRF5 expression in human macrophages. Recent studies demonstrate that IRF4 controls M2 macrophage polarization, while IRF5 regulates the M1 phenotype respectively. We could show that a lenalidomid-mediated M1-phenotype induction is efficiently abrogated by IRF4 overexpression or IRF5 silencing. Overall, these findings unravel a novel role for IKZF1 in orchestrating macrophage polarization via the IRF4/IRF5 pathway. Disclosures No relevant conflicts of interest to declare.

Haematopoietic stem cells (HSCs) reside in hypoxic niches in the bone marrow (BM) and sustain long-life haematopoiesis. HSCs are largely quiescent, self-renew, undergo apoptosis and generate progenitor cells, which differentiate to multiple blood lineages. The strict regulation of the balance between these fate decisions is essential for haematopoiesis and their dysregulation in HSCs and progenitor cells can result in leukaemic transformation. HSCs and leukemic stem cells (LSCs) are suggested to share the same niche and are in need to adapt to hypoxic conditions. Hypoxia-inducible-factor-1α (HIF-1α) is a key mediator of cellular responses to hypoxia and is important for the maintenance of HSC functions under stressful conditions. Furthermore, in chronic myeloid leukaemia (CML) and acute myeloid leukaemia (AML) HIF-1α is essential for LSC maintenance and ablation or knockdown of HIF-1α leads to exhaustion of established LSCs. The aim of this study was to investigate the requirement for HIF-1α in the generation of pre-LSCs and the establishment of LSCs. To investigate the role of HIF-1α in the generation of pre-LSCs we retrovirally transduced haematopoietic stem and progenitor cells (HSPCs) from either WT or HIF1-αfl/fl Vav-iCre with MLL-ENL retroviruses. Next we performed serial re-plating assays under normoxic and hypoxic conditions to generate pre-LSCs. Surprisingly, WT and HIF-1α deficient HSPCs generated comparable numbers of colonies in normoxia and hypoxia (Fig. 1a). In addition no significant difference was found in the immunophenotypic profile of colonies (Figure 1b). Furthermore, microscopic examination indicated that colonies of all genotypes were dense consistent with their transformed shape (Fig. 1c). WT and HIF-1α-deficient pre-LSCs cultured under normoxia and hypoxia had similar cloning efficiency, which is known to directly correlate with the numbers of LSCs in vivo (Fig. 2). These results indicate that HIF-1α is dispensable for the generation of pre-LSCs. To test the role of HIF-1α in establishment of LSCs from pre-LSCs we transplanted pre-LSCs into lethally irradiated mice together with support BM and monitored the mice for disease development. No significant difference was found in disease latency (Fig. 3a) or frequency of LSCs in peripheral blood, bone marrow or spleens (Fig. 3b) indicating that pre-LSCs lacking HIF-1α can efficiently generate LSCs that cause aggressive AML. In conclusion, we provide genetic evidence that HIF-1α is dispensable for the generation of pre-LSCs and the establishment of LSCs from pre-LSCs. These surprising findings, together with published results indicating that HIF-1α is essential for maintenance of LSCs, imply that HIF-1α has different roles at different stages of leukaemic transformation. Further studies are required to explain the distinct roles of HIF-1α in different stages of leukaemogenesis. Disclosures: Ratcliffe: RedOx: Founder Other. Holyoake:Novartis: Membership on an entity’s Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity’s Board of Directors or advisory committees; Ariad: Membership on an entity’s Board of Directors or advisory committees.

Multiple myeloma (MM) is a B-cell neoplasm that is characterized by the accumulation of malignant plasma cells in the bone marrow. Previous molecular studies have largely focused on acquired genetic aberrations in MM. There is increasing evidence that in addition to genetic aberrations epigenetic processes play a major role in carcinogenesis. Aberrant methylation of CpG islands near gene promoter regions is the most widely studied epigenetic abnormality in human malignancies and is associated with loss of gene function. This epigenetic event acts as an alternative to mutations and deletions to disrupt tumor suppressor gene function. The Wnt pathway has been recognized to be essential for normal organ development, and a role for Wnt signal transduction at several stages of lymphocyte differentiation and in the self-renewal of hematopoietic stem cells could be demonstrated. Alterations in the Wnt pathway have been shown to contribute to the pathogenesis of various human malignancies. Epigenetic silencing of the family of secreted frizzled-related proteins (SFRPs), which act as Wnt antagonists, was recently reported in several solid tumors and in acute lymphoblastic leukemia. In order to investigate the potential role of abnormal Wnt signaling in MM, we determined the methylation status of the promoter-associated CpG islands of SFRP-1, 2, 4 and 5 in the MM cell lines U266, LP-1, RPMI-8226 and OPM-2. Methylation-specific polymerase chain reaction (MSP) analysis revealed that promoter hypermethylation of the SFRP genes was a frequent event in MM cell lines (SFRP-1: 2/4, SFRP-2: 2/4, SFRP-4: 1/4 and SFRP-5: 3/4). Aberrant methylation of SFRP-1 and SFRP-2 in MM cell lines was associated with transcriptional silencing, as determined by real-time reverse transcriptase polymerase chain reaction. Treatment of cell lines that carry a hypermethylated SFRP-1 and SFRP-2 gene, respectively, with the demethylating agent 5-aza-2′-deoxycytidine resulted in gene reexpression. We then analyzed by MSP the methylation status of SFRP-1, 2, 4 and 5 in 76 specimens obtained from MM patients. The frequency of aberrant methylation among the primary patient samples was 38.2% (29/76) for SFRP-1, 59.2% (45/76) for SFRP-2, 2.6% (2/76) for SFRP-4 and 7.6% (6/76) for SFRP-5. There was a high incidence of concomitant hypermethylation of SFRP-1 and SRFP-2. We conclude that promoter hypermethylation of the SFRP genes is a novel epigenetic event in MM that may contribute to aberrant activation of the Wnt pathway. Further studies are warranted to elucidate the functional consequences of aberrant Wnt signaling by downregulation of the SFRP genes in the pathogenesis of MM. Additionally, the increasing evidence for the important role of DNA methylation changes in malignant plasma cell disorders may serve as a basis for the use of epigenetically targeted therapeutic approaches in MM in the future.