Abhishek A. Mangaonkar

Short Telomere Syndromes in Clinical Practice: Bridging Bench and Bedside

Abstract Short telomere syndromes (STSs) are accelerated aging syndromes often caused by inheritable gene mutations resulting in decreased telomere lengths. Consequently, organ systems with increased cell turnover, such as the skin, bone marrow, lungs, and gastrointestinal tract, are commonly affected. Owing to diverse clinical presentations, STSs pose a diagnostic challenge, with bone marrow failure and idiopathic pulmonary fibrosis being frequent manifestations, occurring in association with gene mutations involving DKC1 (for expansion of gene symbols, use search tool at www.genenames.org), TERT, TERC, and others. Inherited STSs demonstrate genetic anticipation, occurring at an earlier age with more severe manifestations in the affected progeny. Telomere lengths can be assessed in peripheral blood granulocytes and lymphocytes using a sensitive technique called flow cytometry–fluorescence in situ hybridization, and mutational analysis can be performed using next‐generation sequencing assays. In approximately 40% of patients with shortened telomere lengths, gene mutations cannot be identified due to the fact that all STS‐associated genes have not yet been defined or due to alternative mechanisms of telomere shortening. Danazol, an anabolic steroid, has been associated with hematologic responses in patients with STSs and associated bone marrow failure; however, its reported ability to increase telomerase activity and reduce telomere attrition needs further elucidation. Organ transplant is reserved for patients with end‐organ failure and is associated with substantial morbidity and mortality. Herein, we summarize the clinical and laboratory characteristics of STSs and offer a stepwise approach to diagnose and manage complications in affected patients.

Prognostic interaction between bone marrow morphology and SF3B1 and ASXL1 mutations in myelodysplastic syndromes with ring sideroblasts

Prognostic interaction between bone marrow morphology and SF3B1 and ASXL1 mutations in myelodysplastic syndromes with ring sideroblasts Abhishek A. Mangaonkar, Terra L. Lasho, Christy M. Finke, Naseema Gangat, Aref Al-Kali , Michelle A. Elliott, Kebede H. Begna, Hassan Alkhateeb, Alexandra P. Wolanskyj-Spinner, Curtis A. Hanson, Rhett P. Ketterling, William J. Hogan , Animesh Pardanani, Mark R. Litzow, Ayalew Tefferi and Mrinal M. Patnaik 1

A novel immunohistochemical score to predict early mortality in acute myeloid leukemia patients based on indoleamine 2,3 dioxygenase expression

Indoleamine 2,3 dioxygenase-1 (IDO-1) is an enzyme in the kynurenine pathway which augments tumor-induced immune tolerance. Previous studies in childhood acute myeloid leukemia (AML) have shown a negative correlation of IDO-1 mRNA expression with outcomes. The aim of our study was to develop a practical and objective immunohistochemical technique to quantify IDO-1 expression on diagnostic bone marrow biopsies of AML patients in order to facilitate its use in routine clinical practice. IDO-1 mRNA was extracted from diagnostic bone marrow specimens from 29 AML patients. IDO-1 protein expression was assessed in 40 cases via immunohistochemistry and quantified by a novel ‘composite IDO-1 score’. In a univariate analysis, higher age (p = 0.0018), male gender (p = 0.019), high risk cytogenetics (p = 0.002), higher IDO-1 mRNA (p = 0.005), higher composite IDO-1 score (p < 0.0001) and not undergoing allogeneic stem cell transplant (SCT, p = 0.0005) predicted poor overall survival. In a multivariate model that included the aforementioned variables, higher composite IDO-1 score (p = 0.007) and not undergoing allogeneic SCT (p = 0.007) was found to significantly predict poor outcomes. Further, patients who failed induction had higher composite IDO-1 score (p = 0.01). In conclusion, ‘composite IDO-1 score’ is a prognostic tool that can help identify a certain subset of AML patients with ‘early mortality’. This unique subset of patients can potentially benefit from specific IDO-1 inhibitor therapy, currently in clinical trials.

Patterns of Care and Survival for Elderly Acute Myeloid Leukemia—Challenges and Opportunities

Purpose of ReviewAcute myeloid leukemia (AML) is a disease of the elderly, with a median age of diagnosis in the sixth decade of life. Mortality has declined over the last few years, but this impact is apparent only in the young, fit AML population. Outcomes for the elderly remain poor, with less than 20% 5-year overall survival rates. Hence, there is an unmet need to identify treatment strategies to maximize benefit in this age group.Recent FindingsElderly AML is a difficult entity to treat due to both disease and patient-related factors. Treatment of this group has a lot of inter-physician and inter-institutional variability. Several objective criteria to assess biological age, impact of co-morbidities, and fitness have been published, which could be utilized to make management decisions. For old and unfit AML patients, a variety of novel therapeutic agents are currently being investigated.SummaryObjective analysis of biological age should include assessment of fitness, frailty, and co-morbidities in elderly AML. Future areas of research include development of an objective risk-based approach and its validation in clinical trials, development of novel therapeutic agents, and improvement in supportive care measures.

Prognostic risk model for patients with high-risk polycythemia vera and essential thrombocythemia

ABSTRACT Introduction: Polycythemia Vera (PV) and Essential Thrombocythemia (ET) are the most frequent Philadelphia chromosome-negative myeloproliferative neoplasms, the other entity being myelofibrosis. Management of patients with PV and ET is fraught with difficulties as they have an inherent tendency to cause thrombotic and hemorrhagic events. There are no curative treatment options, therefore it is important that a risk-adapted treatment approach is applied. Areas covered: This review discusses existing literature about prognosis in PV and ET, and addresses critical aspects related to defining ‘high-risk’ disease. In addition to the traditional risk factors such as age and prior thrombotic history, we discuss the prognostic impact of additional parameters such as cardiovascular risk factors, white blood cell count, karyotype and gene mutations. Expert commentary: We use age>60 years, presence of JAK2 mutation and a prior thrombotic history as the principle determinants of ‘high-risk’ for thrombosis in PV and ET, dividing the patients into very-low, low, intermediate and high-risk disease. Typically, low-risk patients are treated either with observation or aspirin alone. High-risk patients require cytoreductive therapies, along with aspirin and/or systemic anticoagulation. Intermediate-risk patients are treated on a case-by-case basis. Further, we aim to maintain a hematocrit <45% with aggressive phlebotomy in patients with PV.

Infrequent occurrence of TET1, TET3 , and ASXL2 mutations in myelodysplastic/myeloproliferative neoplasms

Ten Eleven Translocation (TET) proteins are a family of dioxygenases (TET1, TET2, and TET3) that catalyze the oxidation of 5-methyl-cytosine (5mC) to 5hydroxymehylcytosine (5hmC), 5-formlycytosine (5fC), and 5-carboxylcytosine (5caC). Mutations involving TET2 (4q24) have widely been reported in the context of age-related clonal hematopoiesis (~10% >80 years of age), and hematological malignancies such as myelodysplastic syndromes (MDS 5–20%), myeloproliferative neoplasms (MPN~15%), chronic myelomonocytic leukemia (CMML ~60%), acute myeloid leukemia (AML 8–30%), and T and B cell lymphoproliferative disorders . In CMML, thus far, clonal TET2 mutations in the absence of clonal ASXL1 mutations (ASXL1wt/TET2mt) have been associated with favorable outcomes. Conversely, mutations in TET1 (10q21.3) and TET3 (2p13.1) are extremely infrequent with a large study of 408 MPN, CMML, and AML patients demonstrating no identifiable mutations in these genes. In a recent study, whole exome sequencing was performed in 49 CMML patients resulting in the detection of two loss-of-function, subclonal, TET3 mutations (R148H and S1708fs), both in patients with co-existing TET2 mutations. ASXL2 (additional sex combs-like; 2p23.3) mutations were recently described in adult and pediatric patients with t(8;21)/core binding factor AML (RUNX1–RUNX1T1) (~20%) and were associated with a higher cumulative incidence of relapse. In MDS/MPN overlap syndromes including CMML, thus far, the frequency and prognostic impact of ASXL2 mutations remain unknown. We carried out this study to estimate the frequency and clinical correlates of TET1, TET3, and ASXL2 mutations in patients with MDS/MPN overlap syndromes. Eighty three patients meeting the 2016 World Health Organization (WHO) criteria for CMML (n= 30) and MDS/MPN-Unclassifiable (MDS/MPN-U, n= 47) were included in the study. The median age was 73 years (range, 18–89 years) and 66% were male. All patients had bone marrow (BM) biopsies and cytogenetic studies performed at diagnosis. Target capture-based next generation sequencing (NGS) was carried out on diagnostic BM DNA from all 83 patients for the complete coding regions of the following 42 genes: TET1, TET2,TET3, DNMT3A, IDH1, IDH2, ASXL1, ASXL2, ATM, EED, EZH2, JARID2, SUZ12, BCOR, BCORL1, STAG2, GATA2, TERC, TERT, SRSF2, SF3B1, ZRSR2, U2AF1, PTPN11,PHF6, Tp53, SH2B3, RUNX1, CBL, NRAS, KRAS, JAK2, CSF3R, FLT3, KIT, CALR, MPL, NPM1, CEBPA, IKZF1, ETNK1, and SETBP1 by previously described methods. Paired-end indexed libraries were prepared from individual patient DNA using the NEBNext Ultra Library prep protocol on the Agilent Bravo liquid handler. Capture libraries were assembled according to Nimblegen standard library protocol. Base-calling was performed using Illumina’s RTA version 1.17.21.3. Genome_GPS v4.0.1 (formerly named as TREAT) was employed to analyze the data. Specific variants were included if they were cited by the Catalog of Somatic Mutations in Cancer database (COSMIC, http:// cancer.sanger.ac.uk) and/or if they were found at less than 0.1% by the Exome Aggregation Consortium (ExAC, Broad Institute, Cambridge, MA) and not associated with a COSMIC identifier. Previously annotated singlenucleotide polymorphisms (http//www.hapmap.org) in

miRNA in Pathophysiology of Peripartum Cardiomyopathy (PPCM): A Systemic Review

Peripartum cardiomyopathy (PPCM) was recognized as a clinical entity in the early 1930s; however, the exact mechanism of the disease’s progression remains unknown. The highest incidence of PPCM is in African Americans, and the disease is associated with poor outcomes in elderly and multiparous women. The varying characteristics of patients suggest that genetic susceptibility of the disease could exist. PPCM can be associated with life threatening complications including cardiogenic shock, fatal arrhythmias, and thromboembolic events which can lead to death. Pregnant or lactating PPCM patients can further complicate how clinicians manage them. One recent hypothesis is that 16-kDa N-terminal prolactin fragment (16K PRL) plays a vital role in PPCM by inducing microRNA146a (miRNA146a) which reduces angiogenesis through downregulation of NRAS. miRNAs are small RNAs that were previously described as noncoding RNA that controls the posttranscriptional activity of mRNA. Recent animal studies have identified miRNA146a as a causative factor in PPCM; this discovery is promising and could have clinical implications in future. With growing evidence of miRNA’s involvement in disease, miRNA can add to our current understanding of pathology and could be a potential tool for diagnosis, prognosis, and therapy in PPCM.

Prognostic impact of ASXL1 mutations in patients with myelodysplastic syndromes and multilineage dysplasia with or without ring sideroblasts

INTRODUCTION The 2016 World Health Organization (WHO) classification of myeloid neoplasms reclassified patients with myelodysplastic syndromes (MDS) with multilineage dysplasia (MLD) based on the presence or absence of ring sideroblasts (RS). We performed this study to validate this change in the context of relevant gene mutations. METHODS WHO-defined MDS and MLD were identified with detailed clinical, cytogenetic and outcomes data. A 32-gene targeted exome sequencing panel was performed on bone marrow samples obtained at diagnosis. RESULTS Ninety eight patients were included; 59 (60%) MDS-MLD and 39 (40%) MDS-RS-MLD. There were no significant differences in the median overall survival (OS) in the two groups (25 months each, p = 0.6). Among the myeloid-relevant gene mutations, presence of ASXL1 (HR 2.5, p = 0.005) was identified as an adverse prognostic factor in a multivariate analysis. CONCLUSION While segregation of MDS-MLD based on RS holds little prognostic relevance, ASXL1 mutational status significantly and independently predicts poor outcomes.

Multiple isodicentric Y chromosomes in myeloid malignancies: a unique cytogenetic entity and potential therapeutic target

Abhishek A. Mangaonkar, Mrinal M. Patnaik , Gavin R. Oliver, Kathleen W. Rao, Kathleen Kaiser-Rogers, Jaime I. Davila, Numrah Fadra, Rebecca N. Wehrs, Michelle A. Elliott, Patricia T. Greipp, Kevin C. Halling and Daniel L. Van Dyke Division of Hematology, Mayo Clinic, Rochester, MN, USA; Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA; Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC, USA; Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA

Immune-Mediated Autonomic Neuropathies following Allogeneic Stem Cell Transplantation in Acute Myeloid Leukemia

Background/Aims Autonomic dysfunction (AD) after allogeneic stem cell transplant (SCT) is a rare occurrence and likely immune-mediated in etiology. There is limited literature on this topic and hence, we wish to briefly describe management of two cases at our institution and their outcomes. Methods We retrospectively identified two patients with immune-mediated AD after SCT from our database. Immune-mediated AD was defined as AD secondary to an immune-mediated etiology without an alternative cause and responding to immunosuppression. Results The first case is of a 32-year-old man with acute myeloid leukemia (AML) who underwent double umbilical cord allogeneic SCT. The second patient was a 51-year-old woman with secondary AML who underwent matched-related donor allogeneic SCT. Both underwent an extensive work-up for an underlying etiology prior to treatment with intravenous immunoglobulin (IVIG). Conclusions AD after SCT is a rare yet significant clinical entity. A work-up of underlying etiology should be performed. IVIG is a treatment option for these patients.