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Cancer is driven by somatic mutations that provide a fitness advantage. While targeted therapies often focus on the mutated gene or its direct downstream effectors, imbalances brought on by cell-state alterations may also confer unique vulnerabilities. In myeloproliferative neoplasms (MPN), somatic mutations in the calreticulin (CALR) gene are disease-initiating through aberrant binding of mutant CALR to the thrombopoietin receptor MPL and ligand-independent activation of JAK-STAT signaling. Despite these mechanistic insights into the pathogenesis of CALR-mutant MPN, there are currently no mutant CALR-selective therapies available. Here, we identified differential upregulation of unfolded proteins, the proteasome and the ER stress response in CALR-mutant hematopoietic stem cells (HSCs) and megakaryocyte progenitors. We further found that combined pharmacological inhibition of the proteasome and IRE1-XBP1 axis of the ER stress response preferentially targets Calr-mutated HSCs and megakaryocytic-lineage cells over wild-type cells in vivo, resulting in an amelioration of the MPN phenotype. In serial transplantation assays following combined proteasome/IRE1 inhibition for six weeks, we did not find preferential depletion of Calr-mutant long-term HSCs. Together, these findings leverage altered proteostasis in Calr-mutant MPN to identify combinatorial dependencies that may be targeted for therapeutic benefit and suggest that eradicating disease-propagating Calr-mutant LT-HSCs may require more sustained treatment.

Myeloproliferative neoplasms (MPNs) are chronic hematological malignancies characterized by increased proliferation of MPN stem and myeloid progenitor cells with or without bone marrow fibrosis that typically lead to increased peripheral blood cell counts. The genetic and cytogenetic alterations that initiate and drive the development of MPNs have largely been defined, and we summarize these here.In recent years, advances in understanding the pathogenesis of MPNs have defined a long-preclinical phase in JAK2-mutant MPN, identified genetic loci associated with MPN predisposition and uncovered mechanistic insights in CALR-mutant MPN. The integration of molecular genetics into prognostic risk models is well-established in myelofibrosis and ongoing studies are interrogating the prognostic implications of concomitant mutations in ET and PV. Despite all these advances, the field is deficient in clonally selective therapies to effectively target the MPN clone at any stage of disease, from pre-clinical to advanced. Although the biological understanding of the pathogenesis of MPNs has progressed quickly, substantial knowledge gaps remain, including in the molecular mechanisms underlying MPN progression and myelofibrotic transformation. An ongoing goal for the MPN field is to translate advances in biological understanding to improved treatments for patients.

Annals of hematology 101(11), 2533-2536 (2022). doi:10.1007/s00277-022-04975-9, Published by Springer, Berlin ; Heidelberg ; New York

Lange Zeit blieb unklar, inwieweit immunologische Mechanismen zur Therapie von malignen Erkrankungen beitragen konnen. Mittlerweile ist jedoch bewiesen, dass unser Immunsystem sich als ein effizientes Verteidigungswerkzeug gegenuber malignen Erkrankungen darstellt. Aufgrund zunehmender Erkenntnisse auf dem Gebiet der Tumorimmunologie und neuer immunologischer Therapieansatze, die zunehmend erfolgversprechend sind, ist die Immunonkologie ein groses Teilgebiet der Krebsmedizin geworden. Der vorliegende komprimierte Ubersichtsartikel soll wesentliche Grundlagen der Tumorimmunologie darstellen mit Schwerpunkt auf immunologischen Mechanismen der Tumorabwehr sowie Verteidigungsmechanismen des Tumors. An gesonderten Stellen wird auf einzelne immuntherapeutische Ansatze in der Klinik hingewiesen, um das Gebiet der immunologischen Onkologie in vereinfachter Darstellung einer breiten Zuhorerschaft zuganglich zu machen. Der Artikel ist auf Basis derzeitiger Lehrmeinungen sowie aktueller Fachliteratur entstanden. Die Literaturrecherche erfolgte primar uber die Datenbank PubMed sowie im Hinblick auf derzeit aktive klinische Studien erfolgte die Datenakquisition uber „Clinicaltrials.gov“. Neue immuntherapeutische Ansatze zeigen sehr vielversprechende Ergebnisse. Es ist zu erwarten, dass ein zunehmendes immunologisches Verstandnis auch zu weiteren neuen Therapien auf dem Gebiet der Onkologie fuhren wird. Besonders die Kombination verschiedenster immuntherapeutischer Mechanismen erscheint zukunftsweisend.

Obesity has negative effects on comorbidities, health-related quality of life and survival. Telomere length (TL) changes after bariatric surgery have been reported, but the studies are contradictory, and analyses using state-of-the art techniques for TL measurement, such as flow-FISH, are sparse. We measured TL dynamics via flow-FISH in patients undergoing bariatric surgery and compared their TL with 105 healthy individuals. Patients with obesity who underwent bariatric surgery were included. Lymphocyte and granulocyte absolute and age-adjusted (aa) TL were analyzed by flow-FISH before (preoperative cohort, n = 45) and after surgery (follow-up cohort, n = 35) at month 5.5 ± 3.9 (mean ± standard deviation [SD]). The initial lymphocyte aaTL was significantly shorter (-0.37 kb ± 0.18 kb, P = 0.045) in patients with obesity, while the granulocyte aaTL was not different from that in the healthy comparison population (0.28 kb ± 0.17 kb, P = 0.11). The telomere dynamics after surgery showed an increase in mean TL in both lymphocytes and granulocytes of patients with a pronounced BMI loss of ≥ 10 kg/m

British journal of nutrition : BJN (2021). doi:10.1017/S0007114521000738, Published by Cambridge University Press, Cambridge

International journal of molecular sciences 22(9), 4401 (2021). doi:10.3390/ijms22094401 special issue: "Special issue "Cardiovascular pharmacology and interventions: future directions for cardioprotection" / special issue editors: Bijan Ghaleh, guest editor; Speranza Rubattu, co-guest editor; Alessandro Di Minno, co-guest editor", Published by Molecular Diversity Preservation International, Basel

Summary Dyskeratosis Congenita (DKC) is a systemic disorder caused by mutations resulting in impaired telomere maintenance. Clinical features include bone marrow failure and an increased risk of developing hematological malignancies. There are conflicting data whether androgen derivatives (AD) can elongate telomeres in vivo and whether AD treatment enhances the risk of gaining myelodysplastic syndrome‐related mutations. Seven TERC or TERT‐mutated DKC patients underwent AD treatment. All patients revealed hematological response. Telomere length of lymphocytes and granulocytes increased significantly and no MDS‐related mutations were detected. Pending longer follow‐up, treatment with AD seems to represent an efficient and safe therapy for DKC patients., publishedVersion

Introduction Zinc is an essential trace element having manifold functions within living cells. Zinc deficiency but also zinc excess impairs cell-specific functions whereas a balanced zinc level is required for an adequate cell behavior. Material and methods This study deals with the impact of cellular priming due to stimulation with interleukin (IL)-1, IL-2, IL-4, IL-6 or the chemokine CXCL12a and its subsequent influence on the intracellular free zinc concentration. Since cellular priming and activation is essential for proper immunological reactions, and across that highly cell-type specific, we investigated T cells, B cells, and peripheral blood mononuclear cells (PBMCs). Additionally, alterations of the intracellular zinc content was investigated by inducing zinc deficiency using the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethane-1,2-diamine (TPEN) with subsequent re-supplementation of zinc, hence generating an intracellular zinc flux. Evaluation of zinc staining with FluoZin3-AM, Zinpyr-1 and Zinquin was done by flow cytometry or by fluorescence microscopy. Results Our results indicate that cellular priming for different periods of time (10 minutes/one hour) causes decreased intracellular free zinc concentrations in the FluoZin3-AM staining and increased zinc concentrations stained with Zinpyr-1. Furthermore, zinc supplementation after induced zinc deficiency leads to a fast and excessive rise of the intracellular free zinc levels in most cellular compartments. Conclusion Our study emphasizes the importance of zinc homeostasis and zinc distribution during cellular priming and for certain signaling cascades especially in T and B cells. Moreover, we demonstrated that zinc re-supplementation of zinc deficient cells results in significantly elevated intracellular free zinc concentrations compared to untreated controls. Hence, this underlines the need of a balanced zinc homeostasis for proper immune cell function.

Introduction Recent studies indicate that particularly in a subgroup of younger patients, acute myeloid leukemia (AML) develops due to an inherited genetic predisposition linked to mutations in genes such as ANKRD26, SAMD9, SAMD9-L, GATA-2, genes causing telomere biology disorders or Shwachman-Diamond syndrome. However, the prevalence of so-called "AML predisposition syndromes" (APS) underlying newly diagnosed cases with AML is unknown. Actual screening strategies for APS are based on the family history and clinical/genetic features. There is growing evidence that APS frequently manifest themselves with an oligosymptomatic phenotype or are lacking specific symptoms altogether. Furthermore, molecular analysis of the clonal population without additional analysis of non-clonal cells do not allow the discrimination between inherited and acquired changes. Thus, new approaches to identify the subset of patients with underlying APS in adult newly diagnosed AML patients are needed. One frequent feature observed in APS is younger age at the time of diagnosis and the initial presence of an aberrant karyotype. Along this line, we retrospectively screened the German SAL-AML registry using age and the presence of an aberrant karyotype as pre-defining parameters to analyze the prevalence of APS in this selected cohort. Patients and methods The database of the German SAL-AML registry includes over 5207 patients with AML. We screened for patients below 35 years of age and with any type of numerical or structural chromosomal aberration at first diagnosis. DNA samples of patients achieving cytological remission (CR) and available samples of peripheral blood or bone marrow were selected. CR samples were chosen to reduce potential contamination by malignant AML blasts. Patients were screened for pathogenic variants using a self-designed NGS panel containing the entire coding sequences of ACD, ANKRD26, CTC1, DDX41, DKC1, ERCC6, ETV6, GATA1, GATA2, LIG4, NHP2, NOP10, PARN, POT1, RPA1, RPL11, RPL15, RPL26, RPL35A, RPL5, RPS10, RPS17, RPS19, RPS24, RPS26, RPS7, RTEL1, SAMD9, SAMD9L, SBDS, SRP72, TERC, TERF1, TERF2, TERT, TINF2, TPP1 and WRAP53. An inherited variant was considered in all patients with a variant allele frequency between 40-60% for heterozygous variants and >90% for homozygous ones. To analyze the functional consequence of SAMD9 variants, proliferation assays with HEK293 cells transfected with the respective identified variant was carried out. Results and discussion On the basis of the inclusion criteria mentioned above, we were able to identify 41 patients. All cases except one were considered de novo AML by the treating physicians and received an anthracycline/cytarabine based induction chemotherapy. Mean age of the 41 patients was 26 ± 5 years (mean ± S.D.). Predominant karyotypic aberration were abnormalities of chromosome 8 (18/41) as well as a complex aberrant karyotype (29/41). NGS analysis revealed five different heterozygous mutations in approx. 10% (4/41) of patients: GATA2 c.1009C>T p.(Arg337Ter), SBDS c.183_184delInsCT and c.258+2T>C (both mutations in the same patient), TINF2 c.848C>A p.(Pro283His), SAMD9 c.2854G>C p.(Gly952Arg). The variants in GATA2, SBDS and TINF2 are known to be pathogenic. For SAMD9, in vitro experiments showed increased inhibition of cell growth compared to wild-type supporting the pathogenicity of the mutation. Focusing on the clinical outcome, 50% (2/4) of the identified APS patients received allogeneic transplantation during follow-up compared to 65% (24/37) in the group without detectable mutations. Median survival in the APS group was significantly shorter with 3.2 months compared to 105.3 months in the remaining 37 AML patients (p Conclusions Using age and karyotype as selection criteria, we were able to identify an inherited APS in 10% of newly diagnosed AML patients below 35 years with chromosomal aberrations reaching CR. Obviously, our study is limited by rather stringent inclusion criteria not allowing overall conclusions on the incidence of APS in newly diagnosed AML. However, age and karyotype might provide simple clinical parameters to trigger genetic screening for inherited APS in addition to the actual recommendations. Given the significant difference in survival in patients with and without underlying APS, our study clearly supports inclusion of screening for APS in this cohort pending prospective validation. Figure Disclosures Röllig: Amgen, Astellas, BMS, Daiichi Sankyo, Janssen, Roche: Consultancy; Abbvie, Novartis, Pfizer: Consultancy, Research Funding. Müller-Tidow:Daiichi Sankyo: Research Funding; Pfizer: Research Funding, Speakers Bureau; Janssen-Cilag GmbH: Speakers Bureau; BiolineRx: Research Funding. Panse:Blueprint Medicines: Consultancy, Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Boehringer Ingelheim: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Chugai: Speakers Bureau; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; F. Hoffmann-La Roche Ltd: Consultancy, Membership on an entity's Board of Directors or advisory committees; MSD: Consultancy, Membership on an entity's Board of Directors or advisory committees; Grunenthal: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Apellis: Consultancy, Membership on an entity's Board of Directors or advisory committees. Brümmendorf:Pfizer: Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding; Novartis: Consultancy, Other: travel, accommodation, expenses, Research Funding; Janssen: Consultancy; Merck: Consultancy; Takeda: Consultancy. Jost:Roche: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Astellas: Membership on an entity's Board of Directors or advisory committees; Celgene: Other: travel support; JAZZ: Other: travel support.

Viele uber die Nahrung aufgenommene Stoffe nehmen Einfluss auf die Funktion unseres Immunsystems. Im Fokus steht hier die Wirkung eines einzelnen Elements auf den kompletten menschlichen Korper. Zink ist ein essenzielles Spurenelement, jede unserer Korperzellen ist darauf angewiesen und die Wissenschaft ist sich einig, dass keine uns bekannte Form von Leben ohne Zink moglich ware. Dabei stellt die Diagnose Zinkmangel ein auch in unseren Breiten mogliches Szenario dar.

Dyskeratosis congenita (DKC) is a rare inherited disease of impaired telomere maintenance that progressively leads to multi-organ failure, including the bone marrow. By enhancing telomerase activity, androgen derivatives (ADs) are a potential therapeutic option able to re-elongate previously shortened telomeres. Danazol, oxymetholone, and nandrolone are ADs most frequently used to treat DKC. However, no direct in vitro analyses comparing the efficacy of these ADs have been conducted so far. We therefore treated mononuclear cells derived from peripheral blood and bone marrow of four patients with mutations in telomerase reverse transcriptase (TERT, n = 1),in the telomerase RNA component (TERC, n = 2) and in dyskerin pseudouridine synthase 1 (DKC1, n = 1) and found no substantial differences in the activity of these three agents in patients with TERC/TERT mutations. All AD studied produced comparable improvements of proliferation rates as well as degrees of telomere elongation. Increased TERT expression levels were shown with danazol and oxymetholone. The beneficial effects of all ADs on proliferation of bone marrow progenitors could be reversed by tamoxifen, an estrogen antagonist abolishing estrogen receptor-mediated TERT expression, thereby underscoring the involvement of TERT in AD mechanism of action. In conclusion, no significant differences in the ability to functionally enhance telomerase activity could be observed for the three AD studied in vitro. Physicians therefore might choose treatment based on patients&rsquo, individual co-morbidities, e.g., pre-existing liver disease and expected side-effects.

Introduction: Dyskeratosis Congenita (DKC) is caused by mutations in genes related to telomere maintenance resulting in prematurely shortened telomeres. Clinically, classical DKC is characterized by mucocutaneous abnormalities, bone marrow failure and other variable features such as lung or liver fibrosis. In adults, mono- or oligosymptomatic DKC is typically presenting with a clinically more heterogeneous and often cryptic picture without classical symptoms of DKC. Data on immunodeficiency as a predominant symptom in DKC patients is limited. The common variable immunodeficiency (CVID) represents a heterogenous group of disease with no universally accepted definition. Typically, patients show hypogammaglobulinaemia and impaired vaccine response. In most cases the genetic basis of CVID remains unknown and to date, the disease is primarily via exclusion of other reasons for hypogammaglobulinaemia. In this study, we aimed to retrospectively analyze the frequency and characteristics of adult patients with altered telomere maintenance (manifesting themselves as "cryptic DKC") within a well-defined cohort of patients with clinical findings of CVID. Materials and Methods: 200 patients of the Freiburg registry of adult CVID patients underwent whole-exome sequencing (WES). Diagnosis of CVID was established based on the recommendations of the European Society of Immune Deficiencies. Retrospectively, all patients were screened for mutations/variants in the following DKC causing genes: TERT, RTEL1, DKC1, NHP2, TERC, NOP10, TCAB1, TIN2 and CTC1. Screening identified 23 patients (age: 45 +/- 13 years; mean +/- S.D.) with mutations/polymorphisms in these genes. All identified variants were heterozygous. One patient showed polymorphisms in three different genes. To analyze the functional consequences on telomere maintenance, telomere length (TL) of peripheral blood mononuclear cells (PBMCs) were analyzed via MM-Q-PCR in all 23 patients. Furthermore, Flow-FISH analysis of lymphocytes as well as granulocytes was carried out in 22 and 14 patients, respectively. Results: TL analysis measured with MM-Q-PCR showed in most of the 23 patients shortened TL compared to an age-matched control group. We measured premature TL shortening below the 1% percentile in 44% (10/23) and below the 10% percentile in 52% (12/23). TL determined via flow-FISH showed TL in lymphocytes below the 10% percentile in 64% (14/22) and below 1% in 27% (6/22). WES revealed 24 polymorphisms/mutations in RTEL1 (n=5), TERT (n=3), NHP2 (n=6), DKC1 (n=8) and CTC1 (n=2). Based on bioinformatic prediction, 78 % (19/24) of all polymorphisms were classified as likely benign variants. Two patients with pathogenic mutations were identified: One 30 year old patient with previously described pathogenic TERT mutation (c.1234C>T, p.His412Tyr) was identified showing lymphocyte and granulocyte TL with flow-FISH between the 1% and 10% percentile and below the 1% percentile using MM-Q-PCR. One 23 year old patient with a bioinformatic predicted pathogenic mutation in RTEL1 (c.2313_2315delAGA, p.Glu771del) showed TL in flow-FISH and MM-Q-PCR below the 1% percentile. Of note, this patient developed few years after initial CVID diagnosis severe interstitial lung disease. Three patients were identified with possible DKC showing variants of unknown significance in the RTEL1 (41 years: c.380G>A, p.Arg127Gln) and TERT (65 years: c.3257G>A, p.Arg1086His and 42 years: c.1843G>A, p.Ala615Thr) gene having both TL in lymphocytes/granulocytes (flow-FISH) and leukocytes (MM-Q-PCR) below the 5% percentile. Conclusions: Clinical signs of immunodeficiency can be a rare first manifestation of cryptic/late-onset DKC in adult patients. We found out that at least 1% of all patients with CVID syndrome is caused by mutations typically found in DKC. Our data adds a further important clinical manifestation to the broad clinical spectrum of cryptic DKC. In return, awareness of CVID as a possible first manifestation of cryptic DKC can improve patient management. TL analysis in addition to genetic work-up provides a valuable tool to identify DKC as underlying disease of CVID and other disorders characterized by impaired replicative potential. Disclosures Brümmendorf: Ariad: Consultancy; Merck: Consultancy; University Hospital of the RWTH Aachen: Employment; Pfizer: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Janssen: Consultancy. Beier:Novartis: Honoraria; Repeat Dx: Other: Partner.