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Dyskeratosis congenita (DC) is a bone marrow failure syndrome with extrahematopoietic abnormalities. DC is a paradigmatic telomere biology disorder (TBD) caused by germline mutations in genes responsible for telomere maintenance including TERT. Cryptic TBD is a bone marrow failure syndrome due to premature telomere shortening but without additional symptoms, frequently clinically indistinguishable from severe aplastic anemia (SAA) or hypoplastic myelodysplastic syndrome. We present the complex diagnostic pathway in a boy with a rare germline p.Thr726Met TERT variant with previous reports of SAA association and compromised enzymatic function who presented with juvenile myelomonocytic leukemia, which is a rare myelodysplastic/myeloproliferative neoplasm of childhood.

Precision cancer medicine (PCM) holds great promises to offer more effective therapies to patients based on molecular profiling of their individual tumours. Although the PCM approach seems intuitive, multiple conceptional and structural challenges interfere with the broad implementation of PCM into clinical practice. Accordingly, concerted national and international efforts are needed to guide the further development and broad adoption of PCM in Germany. With support of the 'German Cancer Aid' (Deutsche Krebshilfe [DKH]) a task force 'Molecular Diagnostics and Therapy' was implemented. In two workshops supported by the DKH, delegates from the fourteen comprehensive cancer centresidentified key topics essential to implement quality-guided, harmonized and adaptable PCM. Based on an online questionnaire and using a modified Delphi approach, nine statements were drafted and evaluated within the group. These statements could serve as a basis to define a collaborative strategy for PCM in the future with the aim to sustain and further improve its quality.

Leukemia : normal and malignant hemopoiesis ; a peer-reviewed journal 36, 80-89 (2022). doi:10.1038/s41375-021-01316-z, Published by Springer Nature, London

Der Beitrag möchte die derzeitige Krise der katholischen Kirche einem an Organisationsentwicklung und Konfliktdynamiken interessierten Publikum erschließen. Dabei werden die aktuellen Krisenerfahrungen in den größeren Horizont der mit Modernisierungs­ und Globalisierungsprozessen verbundenen Polarisierungen eingeordnet, wie sie religiöse Gemeinschaften und die Gesellschaft selbst prägen. Diese Konflikte sind in der katholischen Kirche eng mit ihrer Organisationsstruktur verbunden, die theologisch gedeutet und begründet wird. Die verschiedenen Dialogprozesse in der katholischen Kirche lassen sich als Prozesse einer komplexen Organisationsentwicklung verstehen, welche nicht nur Organisationsstrukturen, sondern zugleich die Glaubenskultur und theologische Grundüberzeugungen betreffen. An den Erfahrungen mit der Synode im Bistum Trier werden Merkmale solcher Verständigungsprozesse dargestellt. In der Verschränkung von politischer Arena, Strategieentwicklung und einem Prozess geistlicher Verständigung und Umkehr liegt ihr Spezifikum.

Inflammation-induced thrombosis represents a severe complication in patients with myeloproliferative neoplasms (MPN) and in those with kidney dysfunction. Overlapping disease-specific attributes suggest common mechanisms involved in MPN pathogenesis, kidney dysfunction, and thrombosis. Data from 1420 patients with essential thrombocythemia (ET, 33.7%), polycythemia vera (PV, 38.5%), and myelofibrosis (MF, 27.9%) were extracted from the bioregistry of the German Study Group for MPN. The total cohort was subdivided according to the calculated estimated glomerular filtration rate (eGFR, (mL/min/1.73 m2)) into eGFR1 (≥90, 21%), eGFR2 (60–89, 56%), and eGFR3 (&lt, 60, 22%). A total of 29% of the patients had a history of thrombosis. A higher rate of thrombosis and longer MPN duration was observed in eGFR3 than in eGFR2 and eGFR1. Kidney dysfunction occurred earlier in ET than in PV or MF. Multiple logistic regression analysis identified arterial hypertension, MPN treatment, increased uric acid, and lactate dehydrogenase levels as risk factors for kidney dysfunction in MPN patients. Risk factors for thrombosis included arterial hypertension, non-excessive platelet counts, and antithrombotic therapy. The risk factors for kidney dysfunction and thrombosis varied between MPN subtypes. Physicians should be aware of the increased risk for kidney disease in MPN patients, which warrants closer monitoring and, possibly, early thromboprophylaxis.

Cancers 13(12), 2905 (2021). doi:10.3390/cancers13122905, Published by MDPI, Basel

Background Dyskeratosis congenita (DKC) and idiopathic aplastic anemia (AA) are bone marrow failure syndromes that share characteristics of premature aging with severe telomere attrition. Aging is also reflected by DNA methylation changes, which can be utilized to predict donor age. There is evidence that such epigenetic age predictions are accelerated in premature aging syndromes, but it is yet unclear how this is related to telomere length. DNA methylation analysis may support diagnosis of DKC and AA, which still remains a challenge for these rare diseases. Results In this study, we analyzed blood samples of 70 AA and 18 DKC patients to demonstrate that their epigenetic age predictions are overall increased, albeit not directly correlated with telomere length. Aberrant DNA methylation was observed in the gene PRDM8 in DKC and AA as well as in other diseases with premature aging phenotype, such as Down syndrome and Hutchinson-Gilford-Progeria syndrome. Aberrant DNA methylation patterns were particularly found within subsets of cell populations in DKC and AA samples as measured with barcoded bisulfite amplicon sequencing (BBA-seq). To gain insight into the functional relevance of PRDM8, we used CRISPR/Cas9 technology to generate induced pluripotent stem cells (iPSCs) with heterozygous and homozygous knockout. Loss of PRDM8 impaired hematopoietic and neuronal differentiation of iPSCs, even in the heterozygous knockout clone, but it did not impact on epigenetic age. Conclusion Taken together, our results demonstrate that epigenetic aging is accelerated in DKC and AA, independent from telomere attrition. Furthermore, aberrant DNA methylation in PRDM8 provides another biomarker for bone marrow failure syndromes and modulation of this gene in cellular subsets may be related to the hematopoietic and neuronal phenotypes observed in premature aging syndromes. Graphical abstract

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

Dyskeratosis congenita (DKC) is a paradigmatic telomere disorder characterized by substantial and premature telomere shortening, bone marrow failure, and a dramatically increased risk of developing myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML). DKC can occur as a late-onset, so-called cryptic form, with first manifestation in adults. Somatic MDS-related mutations are found in up to 35% of patients with acquired aplastic anemia (AA), especially in patients with short telomeres. The aim of our study was to investigate whether cryptic DKC is associated with an increased incidence of MDS-related somatic mutations, thereby linking the accelerated telomere shortening with the increased risk of MDS/AML. Samples from 15 adult patients (median age: 42 years, range: 23-60 years) with molecularly confirmed cryptic DKC were screened using next-generation gene panel sequencing to detect MDS-related somatic variants. Only one of the 15 patients (7%) demonstrated a clinically relevant MDS-related somatic variant. This incidence was dramatically lower than formerly described in acquired AA. Based on our data, we conclude that clonal evolution of subclones carrying MDS-related mutations is not the predominant mechanism for MDS/AML initiation in adult cryptic DKC patients.

Introduction: The unfolded protein response (UPR) is a stress sensing signaling network that is activated upon endoplasmic reticulum (ER) stress, a condition characterized by an accumulation of mis- and unfolded proteins in the ER. To retain a functional cell metabolism, UPR activation increases protein folding and degradation. Acute myeloid leukemia (AML) stem cells are prone to develop ER stress, due to their oncogene-driven metabolism and the bone marrow niche, where they face stressors like hypoxia or nutrient fluctuations. Our preliminary work showed enhanced UPR gene expression levels, especially of IRE1α and XBP1, in different AML subtypes. Patients with high XBP1 mRNA expression had an inferior overall survival rate compared to patients with low XBP1 mRNA expression. Aims: We studied the role of elevated UPR signaling in AML therapy resistance and assessed the therapeutic potential of IRE1α-XBP1 inhibitor STF-083010 (STF) as a new strategy in different AML subtypes, including FLT3-ITD + AML. Methods: Human MV4-11 (FLT3-ITD), RS4-11 (FLT3 wildtype; WT), NB-4 (PML-RARα), THP-1 (MLLr) cells, and murine 32D cells transduced with FLT3-ITD or FLT3 WT were analyzed via western blot and RT-PCR. Metabolic activity was assessed by MTT assay, cell death and apoptosis were measured with propidium iodide (PI) or Annexin V staining using flow cytometry. FLT3 cell surface expression was measured via flow cytometry. The clonogenic potential was determined in CFU assays, using patient-derived mononuclear and CD34 + cells. For hypoxic experiments, MV4-11 cells were cultivated under hypoxia (3 % O 2) and cells were subjected to phosphoproteomic analysis, which was performed by mass spectrometry. Conditional Mx1-Cre/XBP1 fl/fl knockout mice were generated and deletion of XBP1 was induced by IP injection of Polyinosinic-polycytidylic acid (Poly(I:C)). Bone marrow and spleen cells were analyzed via flow cytometry and RT-PCR. Results: Treatment with FLT3 TKI AC220 specifically enhanced IRE1α mRNA (9.3-fold, p0.05). Analysis of phosphoproteomics revealed a less active FLT3 signaling under hypoxia. Intriguingly, the combination of IRE1α and FLT3 inhibition overcame the resistance towards AC220 under hypoxia and significantly induced cell death. Conclusion: IRE1α-XBP1 signaling is activated in different AML subtypes including FLT3-ITD + and is further enhanced by hypoxia present in the bone marrow niche. Targeting IRE1α in FLT3-ITD + cells effectively decreases clonogenic growth and induces apoptosis. Our data demonstrate that hypoxia-mediated resistance against AC220 can be overcome by simultaneous IRE1α inhibition. Genetic deletion of XBP1 does not harm steady-state murine hematopoiesis, rendering XBP1 an excellent therapeutic target. Disclosures Koschmieder: CTI: Membership on an entity's Board of Directors or advisory committees, Other; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Baxalta: Membership on an entity's Board of Directors or advisory committees, Other; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); AOP Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Ariad: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Shire: Honoraria, Other; Image Biosciences: Other: Travel support; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Geron: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Karthos: Other: Travel support; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Alexion: Other: Travel support; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Abbvie: Other: Travel support; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees. Brümmendorf: Bristol Myers: Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria; Novartis: Honoraria, Patents & Royalties, Research Funding; Repeat Diagnostics: Research Funding; Takepart Media: Honoraria.

Introduction: Telomere biology disorders (TBD) are caused by mutations affecting proper telomere maintenance resulting in premature telomere shortening. Telomere length (TL) assessment is currently being used for screening and diagnosis of TBD of which Dyskeratosis congenita (DKC) is the most prominent TBD subtype typically found in children and adolescents. In adults, TBDs are characterized by a broad spectrum of more "cryptic" diverging mono- or oligosymptomatic clinical manifestations such as bone marrow failure (BMF), hepatopathy or interstitial lung disease (ILD). However, despite growing general clinical awareness and exertion of improved TL screening strategies, insufficient data are available about the clinical course of adult, late-onset TBDs. Here, we present a series of 41 consecutive adult TBD cases from 2014 to 2021 identified through the Aachen Telomeropathy registry. Methods and Patients: Median follow-up of the cohort was 2.0 (range 0-6.2) years. In 39/41 patients TBD diagnosis was established based on coexistence of the following three criteria: 1.) Identification of pathogenic variant in a known TBD-related gene via next-generation panel sequencing (NGS) or sequential whole exome sequencing (WES). 2.) The presence of prematurely shortened TL below the 1% percentile (39/41) or 5% percentile (2/41) in the lymphocyte gate detected by flow-FISH and 3.) the presence of BMF or ILD as predominant clinical manifestation. In 2 out of 41 cases, WES did not identify a definitive pathogenic variant. Here, diagnosis of TBD was established due to short telomere below the 1% percentile, BMF and the presence of typical DKC stigmata, other TBD symptoms and a positive family history. Results: Mean age of our cohort was 35.9 ± 17.6 years. 49% (n=20) of patients were females. Results of the genetic screening revealed heterozygous pathogenic variants in TERC (n=14) and TERT (n=11) as the most frequent variants, followed by RTEL1 (n=6), TIN2 (n=1), CTC1 (n=1) and DKC1 (n=1). Homozygous or compound heterozygous pathogenic variants were found for CTC1 (n=2), NHP2 (n=2) or TCAB1 (n=1). 46% (n=19) of patients had a positive family history. BMF was the most frequent symptom with 93% (n=38) presenting with leukopenia, 78% (n=32) with anemia and 76% (n=31) with thrombocytopenia. ILD was suspected/confirmed clinically in 44% (n=18), hepatopathies in 29% (n=12) and cancer in 12% of the patients in past medical history (n=5, liposarcoma, breast cancer, Hodgkin lymphoma, diffuse large B-cell lymphoma, endometrial cancer). Symptoms of the typical DKC triad (leukoplakia, nail dystrophy, abnormal skin pigmentation) were observed in 41% (n=17). Of those, 76% (13/17) presented with only one or two clinical signs. Based on past medical history, the onset of first TBD manifestation was observed at a mean age of 26.9 ± 18.3 years. Time from first symptom observed to the diagnosis of TBD was 8.2 ± 9.5 years. 22% (n=9) patients died during follow-up with mean time of 11.7 ± 10.1 years from first manifestation of TBD to death. Regarding treatment, 39% (n=16) were listed for allogeneic stem cell transplantation (allo Tx), but only 38% (6/16) of these eventually received allo Tx. Immunosuppressive therapy with ATG and CSA was carried out in 12% (n=5) of the patients with no patient responding to treatment. Eltrombopag was given in 5% of cases (n=2) without response. 15% (n=6) received androgen treatment with danazol as the most frequently used drug in five of the six reported cases. All patients showed a response at least in one hematological lineage. Conclusions: Our data support the notion that despite the recent progress in screening and genetic diagnostics, late-onset TBD is still frequently underdiagnosed with several years from first manifestation of disease to diagnosis. Implementation of routine screening for TBD might improve the rate of correct TBD diagnosis and could help to avoid ineffective treatments. Disclosures Beier: Pfizer: Membership on an entity's Board of Directors or advisory committees; Jazz: Other: Travel reembursement; Alexion: Speakers Bureau. Roeth: Novartis: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Kira: Consultancy, Honoraria; Bioverativ, a Sanofi company: Consultancy, Honoraria; Roche: Consultancy, Honoraria, Research Funding; Apellis Pharmaceuticals: Consultancy, Honoraria; Alexion Pharmaceuticals Inc.: Consultancy, Honoraria. Platzbecker: AbbVie: Honoraria; Novartis: Honoraria; Celgene/BMS: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Geron: Honoraria. Radsak: Novartis: Consultancy, Honoraria, Other: e.g. travel support; JAZZ: Other: e.g. travel support; Takeda: Consultancy, Honoraria; Celgene/BMS: Consultancy, Honoraria, Other: e.g. travel support; Daiichi Sankyo: Consultancy, Honoraria, Other: e.g. travel support; Astellas: Other: e.g. travel support; Incyte: Consultancy, Honoraria; Corat: Consultancy, Honoraria; Cogent Biosciences: Consultancy, Honoraria; TEVA: Consultancy, Honoraria; Otsuka: Consultancy, Honoraria; Amgen: Other: e.g. travel support; Abbvie: Other: e.g. travel support. Schafhausen: Blueprint Medicines: Membership on an entity's Board of Directors or advisory committees; Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Swedish Orphan Biovitrum AB: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees. Corbacioglu: Gentium/Jazz Pharmaceuticals: Consultancy, Honoraria. Heuser: AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria; BergenBio: Research Funding; BMS/Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees, Research Funding; Jazz: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer Pharma AG: Research Funding; Astellas: Research Funding; Karyopharm: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Tolremo: Membership on an entity's Board of Directors or advisory committees. Koschmieder: Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Karthos: Other: Travel support; Shire: Honoraria, Other; CTI: Membership on an entity's Board of Directors or advisory committees, Other; Sanofi: Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Geron: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Alexion: Other: Travel support; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding; Ariad: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support); Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Baxalta: Membership on an entity's Board of Directors or advisory committees, Other; Abbvie: Other: Travel support; Image Biosciences: Other: Travel support; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; AOP Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: (e.g. travel support), Research Funding. Panse: Blueprint Medicines: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Chugai: 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; Alexion: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; MSD: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Grunenthal: 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; Apellis Pharmaceuticals: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Isfort: Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel reimbursement; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel reimbursement; Ariad: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria; Hexal: Other: Travel reimbursement; Mundipharma: Other: Travel reimbursement; Amgen: Other: Travel reimbursement; Roche: Other: Travel reimbursement; Alexion: Other: Travel reimbursement. Brummendorf: Bristol Myers: Research Funding; Janssen: Honoraria; Novartis: Honoraria, Patents & Royalties, Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Repeat Diagnostics: Research Funding; Takepart Media: Honoraria.

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.

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.

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.

Tyrosine kinase inhibitor (TKI) therapy effectively blocks oncogenic Bcr-Abl signaling and induces molecular remission in the majority of CML patients. However, the disease-driving stem cell population is not fully targeted by TKI therapy in the majority of patients, and leukemic stem cells (LSCs) capable of re-inducing the disease can persist. In TKI-resistant CML, STAT3 inhibition was previously shown to reduce malignant cell survival. Here, we show therapy-resistant cell-extrinsic STAT3 activation in TKI-sensitive CML cells, using cell lines, HoxB8-immortalized murine BM cells, and primary human stem cells. Moreover, we identified JAK1 but not JAK2 as the STAT3-activating kinase by applying JAK1/2 selective inhibitors and genetic inactivation. Employing an IL-6-blocking peptide, we identified IL-6 as a mediator of STAT3 activation. Combined inhibition of Bcr-Abl and JAK1 further reduced CFUs from murine CML BM, human CML MNCs, as well as CD34+ CML cells, and similarly decreased LT-HSCs in a transgenic CML mouse model. In line with these observations, proliferation of human CML CD34+ cells was strongly reduced upon combined Bcr-Abl and JAK1 inhibition. Remarkably, the combinatory therapy significantly induced apoptosis even in quiescent LSCs. Our findings suggest JAK1 as a potential therapeutic target for curative CML therapies.

Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPN) comprise a heterogeneous group of chronic hematologic malignancies. The quality of life, morbidity, and mortality of patients with MPN are primarily affected by disease-related symptoms, thromboembolic and hemorrhagic complications, and progression to myelofibrosis and acute leukemia. Major bleeding represents a common and important complication in MPN, and the incidence of such bleeding events will become even more relevant in the future due to the increasing disease prevalence and survival of MPN patients. This review discusses the causes, differential diagnoses, prevention, and management of bleeding episodes in patients with MPN, aiming at defining updated standards of care in these often challenging situations.

Magnesium alloys are currently subject to much research for use in biodegradable implant applications. The challenge in this field of material development comprises the design of an alloy that provides adequate mechanical and corrosion properties combined with an excellent biocompatibility. While there are many approaches in current literature only one Mg-based application shows the potential to hit the market. MAGNEZIX® Compression Screws are the world’s first approved/CE-certified magnesium-based implants designed for use in biodegradable osteosyntheses applications in humans. Therefore, this paper focusses on challenges and current clinical results achieved by means of degradable compression screws. Insights into the screws’ process chain and approval processes are given. As these innovative screws have already been on the market for 2 years long-term results based on their use in surgery are discussed.

Myeloproliferative neoplasms (MPNs) often carry JAK2(V617F), MPL(W515L), or CALR(del52) mutations. Current treatment options for MPNs include cytoreduction by hydroxyurea and JAK1/2 inhibition by ruxolitinib, both of which are not curative. We show here that cell lines expressing JAK2(V617F), MPL(W515L), or CALR(del52) accumulated reactive oxygen species-induced DNA double-strand breaks (DSBs) and were modestly sensitive to poly-ADP-ribose polymerase (PARP) inhibitors olaparib and BMN673. At the same time, primary MPN cell samples from individual patients displayed a high degree of variability in sensitivity to these drugs. Ruxolitinib inhibited 2 major DSB repair mechanisms, BRCA-mediated homologous recombination and DNA-dependent protein kinase-mediated nonhomologous end-joining, and, when combined with olaparib, caused abundant accumulation of toxic DSBs resulting in enhanced elimination of MPN primary cells, including the disease-initiating cells from the majority of patients. Moreover, the combination of BMN673, ruxolitinib, and hydroxyurea was highly effective in vivo against JAK2(V617F)+ murine MPN-like disease and also against JAK2(V617F)+, CALR(del52)+, and MPL(W515L)+ primary MPN xenografts. In conclusion, we postulate that ruxolitinib-induced deficiencies in DSB repair pathways sensitized MPN cells to synthetic lethality triggered by PARP inhibitors.

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.