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  • 1
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 75, No. 22_Supplement_2 ( 2015-11-15), p. PR03-PR03
    Abstract: Acute myeloid leukemia is heterogeneous with respect to clinical outcome and molecular pathogenesis. Approximately 20% of AML cases are refractory to induction chemotherapy, and about 50% of patients ultimately relapse within a time interval that ranges from months to years. At the molecular level, diverse chromosomal abnormalities and genetic mutations have been observed across patients1. Although several clinical factors (age, white blood cell count), cytogenetic aberrations (t[15;17] translocation, loss of chromosome 5) 2-4, and genetic mutations (DNMT3A, FLT3) have been associated with differences in survival 5,6, these factors are of limited prognostic utility. Moreover, few studies have integrated sequence data with clinical and cytogentic factors to build predictive models of patient outcome. Here, we sought to identify genomic predictors of refractory disease or early relapse. We used whole genome and exome sequencing to analyze the genomes of 71 adult de novo AML patients treated with anthracycline and cytarabine-based induction chemotherapy. Of these, 34 had refractory disease or relapsed within 6 months, 12 relapsed in 6-12 months, and 25 had a long first remission ( & gt;12 months). We also developed an enhanced exome sequencing (EES) approach to identify and follow leukemia-associated variants over time. In 12 additional patients that achieved morphologic remission after induction chemotherapy, we used EES to identify and track variants at time of diagnosis, time of morphologic remission (roughly 30 days later), and a final time point corresponding to eventual relapse (n=8) or extended remission (n=4). No novel coding or non-coding variants present at the time of diagnosis were found to be predictive of refractory disease or early relapse. Using EES, however, we were able to detect leukemia-associated variants in the initial remission bone marrow in all eight patients who eventually relapsed. One persistent leukemia-associated variant was also detected in one patient still in remission, but all other variants in that patient were eliminated. We also detected 64 somatic variants that became enriched following chemotherapy, but were not detected in the original leukemic cells. These may represent relapse-specific variants or oligoclonal hematopoiesis after bone marrow recovery. Overall, our data suggest that the persistence of leukemia-associated variants after bone marrow recovery from cytotoxic therapy is strongly correlated with relapse, and may be used to complement more traditional, morphologic measures of leukemic cell clearance. 1. Cancer Genome Atlas Research N. Genomic and epigenomic landscapes of adult de novo acute myeloid leukemia. The New England Journal of Medicine 2013;368:2059-74. 2. Byrd JC, Mrozek K, Dodge RK, et al. Pretreatment cytogenetic abnormalities are predictive of induction success, cumulative incidence of relapse, and overall survival in adult patients with de novo acute myeloid leukemia: results from Cancer and Leukemia Group B (CALGB 8461). Blood 2002;100:4325-36. 3. Grimwade D, Hills RK, Moorman AV, et al. Refinement of cytogenetic classification in acute myeloid leukemia: determination of prognostic significance of rare recurring chromosomal abnormalities among 5876 younger adult patients treated in the United Kingdom Medical Research Council trials. Blood 2010;116:354-65. 4. Schlenk RF, Dohner K, Krauter J, et al. Mutations and treatment outcome in cytogenetically normal acute myeloid leukemia. The New England Journal of Medicine 2008;358:1909-18. 5. Kihara R, Nagata Y, Kiyoi H, et al. Comprehensive analysis of genetic alterations and their prognostic impacts in adult acute myeloid leukemia patients. Leukemia 2014;28:1586-95. 6. Ley TJ, Ding L, Walter MJ, et al. DNMT3A mutations in acute myeloid leukemia. The New England Journal of Medicine 2010;363:2424-33. This abstract is also presented as a poster at the Translation of the Cancer Genome conference. Citation Format: Jeffery M. Klco, Christopher A. Miller, Malachi Griffith, Allegra Petti, David H. Spencer, Shamika Ketkar-Kulkarni, Lukas D. Wartman, Matthew Christopher, Tamara L. Lamprecht, Jacqueline E. Payton, Jack Baty, Sharon E. Heath, Obi L. Griffith, Dong Shen, Jasreet Hundal, Gue Su Chang, Robert S. Fulton, Michelle O'laughlin, Catrina Fronick, Vincent Magrini, Ryan Demeter, David E. Larson, Shashikant Kulkarni, Bradley A. Ozenberger, John S. Welch, Matthew J. Walker, Timothy A. Graubert, Peter Westervelt, Jerald P. Radich, Daniel C. Link, Elaine R. Mardis, John F. DiPersio, Richard K. Wilson. Genomic approaches for risk assessment in acute myeloid leukemia. [abstract]. In: Proceedings of the AACR Special Conference on Computational and Systems Biology of Cancer; Feb 8-11 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 2):Abstract nr PR03.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
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    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2015
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  • 2
    In: Blood, American Society of Hematology, Vol. 118, No. 21 ( 2011-11-18), p. 404-404
    Abstract: Abstract 404 To characterize the genomic events associated with distinct subtypes of AML, we used whole genome sequencing to compare 24 tumor/normal sample pairs from patients with normal karyotype (NK) M1-AML (12 cases) and t(15;17)-positive M3-AML (12 cases). All single nucleotide variants (SNVs), small insertions and deletions (indels), and cryptic structural variants (SVs) identified by whole genome sequencing (average coverage 28x) were validated using sample-specific custom Nimblegen capture arrays, followed by Illumina sequencing; an average coverage of 972 reads per somatic variant yielded 10,597 validated somatic variants (average 421/genome). Of these somatic mutations, 308 occurred in 286 unique genes; on average, 9.4 somatic mutations per genome had translational consequences. Several important themes emerged: 1) AML genomes contain a diverse range of recurrent mutations. We assessed the 286 mutated genes for recurrency in an additional 34 NK M1-AML cases and 9 M3-AML cases. We identified 51 recurrently mutated genes, including 37 that had not previously been described in AML; on average, each genome had 3 recurrently mutated genes (M1 = 3.2; M3 = 2.8, p = 0.32). 2) Many recurring mutations cluster in mutually exclusive pathways, suggesting pathophysiologic importance. The most commonly mutated genes were: FLT3 (36%), NPM1 (25%), DNMT3A (21%), IDH1 (18%), IDH2 (10%), TET2 (10%), ASXL1 (6%), NRAS (6%), TTN (6%), and WT1 (6%). In total, 3 genes (excluding PML-RARA) were mutated exclusively in M3 cases. 22 genes were found only in M1 cases (suggestive of alternative initiating mutations which occurred in methylation, signal transduction, and cohesin complex genes). 25 genes were mutated in both M1 and M3 genomes (suggestive of common progression mutations relevant for both subtypes). A single mutation in a cell growth/signaling gene occurred in 38 of 67 cases (FLT3, NRAS, RUNX1, KIT, CACNA1E, CADM2, CSMD1); these mutations were mutually exclusive of one another, and many of them occurred in genomes with PML-RARA, suggesting that they are progression mutations. We also identified a new leukemic pathway: mutations were observed in all four genes that encode members of the cohesin complex (STAG2, SMC1A, SMC3, RAD21), which is involved in mitotic checkpoints and chromatid separation. The cohesin mutations were mutually exclusive of each other, and collectively occur in 10% of non-M3 AML patients. 3) AML genomes also contain hundreds of benign “passenger” mutations. On average 412 somatic mutations per genome were translationally silent or occurred outside of annotated genes. Both M1 and M3 cases had similar total numbers of mutations per genome, similar mutation types (which favored C 〉 T/G 〉 A transitions), and a similar random distribution of variants throughout the genome (which was affected neither by coding regions nor expression levels). This is consistent with our recent observations of random “passenger” mutations in hematopoietic stem cell (HSC) clones derived from normal patients (Ley et al manuscript in preparation), and suggests that most AML-associated mutations are not pathologic, but pre-existed in the HSC at the time of initial transformation. In both studies, the total number of SNVs per genome correlated positively with the age of the patient (R2 = 0.48, p = 0.001), providing a possible explanation for the increasing incidence of AML in elderly patients. 4) NK M1 and M3 AML samples are mono- or oligo-clonal. By comparing the frequency of all somatic mutations within each sample, we could identify clusters of mutations with similar frequencies (leukemic clones) and determined that the average number of clones per genome was 1.8 (M1 = 1.5; M3 = 2.2; p = 0.04). 5) t(15;17) is resolved by a non-homologous end-joining repair pathway, since nucleotide resolution of all 12 t(15;17) breakpoints revealed inconsistent micro-homologies (0 – 7 bp). Summary: These data provide a genome-wide overview of NK and t(15;17) AML and provide important new insights into AML pathogenesis. AML genomes typically contain hundreds of random, non-genic mutations, but only a handful of recurring mutated genes that are likely to be pathogenic because they cluster in mutually exclusive pathways; specific combinations of recurring mutations, as well as rare and private mutations, shape the leukemia phenotype in an individual patient, and help to explain the clinical heterogeneity of this disease. Disclosures: Westervelt: Novartis: Speakers Bureau.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2011
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  • 3
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 118, No. 49 ( 2021-12-07)
    Abstract: Acute myeloid leukemia (AML) patients rarely have long first remissions (LFRs; 〉 5 y) after standard-of-care chemotherapy, unless classified as favorable risk at presentation. Identification of the mechanisms responsible for long vs. more typical, standard remissions may help to define prognostic determinants for chemotherapy responses. Using exome sequencing, RNA-sequencing, and functional immunologic studies, we characterized 28 normal karyotype (NK)-AML patients with 〉 5 y first remissions after chemotherapy (LFRs) and compared them to a well-matched group of 31 NK-AML patients who relapsed within 2 y (standard first remissions [SFRs]). Our combined analyses indicated that genetic-risk profiling at presentation (as defined by European LeukemiaNet [ELN] 2017 criteria) was not sufficient to explain the outcomes of many SFR cases. Single-cell RNA-sequencing studies of 15 AML samples showed that SFR AML cells differentially expressed many genes associated with immune suppression. The bone marrow of SFR cases had significantly fewer CD4 + Th1 cells; these T cells expressed an exhaustion signature and were resistant to activation by T cell receptor stimulation in the presence of autologous AML cells. T cell activation could be restored by removing the AML cells or blocking the inhibitory major histocompatibility complex class II receptor, LAG3. Most LFR cases did not display these features, suggesting that their AML cells were not as immunosuppressive. These findings were confirmed and extended in an independent set of 50 AML cases representing all ELN 2017 risk groups. AML cell–mediated suppression of CD4 + T cell activation at presentation is strongly associated with unfavorable outcomes in AML patients treated with standard chemotherapy.
    Type of Medium: Online Resource
    ISSN: 0027-8424 , 1091-6490
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    Language: English
    Publisher: Proceedings of the National Academy of Sciences
    Publication Date: 2021
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  • 4
    In: New England Journal of Medicine, Massachusetts Medical Society, Vol. 379, No. 24 ( 2018-12-13), p. 2330-2341
    Type of Medium: Online Resource
    ISSN: 0028-4793 , 1533-4406
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    Language: English
    Publisher: Massachusetts Medical Society
    Publication Date: 2018
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  • 5
    In: New England Journal of Medicine, Massachusetts Medical Society, Vol. 375, No. 21 ( 2016-11-24), p. 2023-2036
    Type of Medium: Online Resource
    ISSN: 0028-4793 , 1533-4406
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    Language: English
    Publisher: Massachusetts Medical Society
    Publication Date: 2016
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  • 6
    In: New England Journal of Medicine, Massachusetts Medical Society, Vol. 384, No. 10 ( 2021-03-11), p. 924-935
    Type of Medium: Online Resource
    ISSN: 0028-4793 , 1533-4406
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    Language: English
    Publisher: Massachusetts Medical Society
    Publication Date: 2021
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  • 7
    In: JAMA, American Medical Association (AMA), Vol. 314, No. 8 ( 2015-08-25), p. 811-
    Type of Medium: Online Resource
    ISSN: 0098-7484
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    Language: English
    Publisher: American Medical Association (AMA)
    Publication Date: 2015
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  • 8
    In: New England Journal of Medicine, Massachusetts Medical Society, Vol. 361, No. 11 ( 2009-09-10), p. 1058-1066
    Type of Medium: Online Resource
    ISSN: 0028-4793 , 1533-4406
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    Language: English
    Publisher: Massachusetts Medical Society
    Publication Date: 2009
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  • 9
    In: New England Journal of Medicine, Massachusetts Medical Society, Vol. 363, No. 25 ( 2010-12-16), p. 2424-2433
    Type of Medium: Online Resource
    ISSN: 0028-4793 , 1533-4406
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    Language: English
    Publisher: Massachusetts Medical Society
    Publication Date: 2010
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  • 10
    In: Blood, American Society of Hematology, Vol. 138, No. Supplement 1 ( 2021-11-05), p. 800-800
    Abstract: Background: A normal karyotype is the most common cytogenetic finding in acute myeloid leukemia cells ("NK-AML") and has highly variable and difficult to predict outcomes at presentation. Refinements introduced with the ELN 2017 Criteria (presence or absence of mutations in NPM1, FLT3-ITD, and/or biallelic CEBPA mutations) have improved--but not completely solved--up-front risk classification. NK-AML patients with very long first remissions after chemotherapy only are rare, and their genetic and epigenetic characteristics have not yet been definitively evaluated, but could potentially provide clues regarding determinants that affect chemotherapy responses. Results: Using exome sequencing, RNA-sequencing, and functional studies, we performed an in-depth characterization of 28 de novo adult NK-AML patients with & gt;5 year, Long First Remissions (LFR) after chemotherapy only (7+3 with HiDAC consolidation). As comparators, we studied a well-matched group of 31 NK-AML patients who relapsed within 2 years (Standard First Remissions, SFR). None of the patients in either group received an allogeneic transplant in first remission. Bulk RNA sequencing and targeted investigation of cell type proportions and pathways expected to be relevant for chemotherapy sensitivity (i.e. cell cycle, DNA repair, or AraC responsiveness) revealed no significant differences between LFR and SFR AML samples. However, single cell RNA sequencing (sc-RNAseq) analyses of genetically-defined AML cells from 8 LFR and 7 SFR cases showed that SFR AML cells expressed significantly higher levels of stem cell markers, and of several immunomodulatory genes (MHC class II, CD200, MRC1). Combined sc-RNAseq and flow cytometry analyses of the AML bone marrow samples from LFR patients revealed well-preserved CD4 and CD8 populations that responded robustly to TCR-mediated activation, achieved through CD3/28 bead stimulation. In contrast, SFR AML marrows had reduced numbers of immune cells (particularly of CD4 Th1 cells) and their residual T cells expressed an exhaustion signature. TCR-mediated T cell activation was blocked in the SFR samples by the presence of the AML cells in the bone marrow samples: removing the AML cells released this blockade. Evaluation of T cell immune checkpoints and their putative ligands revealed LAG3 to be a leading candidate for immune suppression, because of its high expression in SFR T cells, and because the genes encoding its major ligands (MHC Class II) were highly expressed in SFR AML cells. Indeed, blocking the inhibitory receptor LAG-3 was able to reverse the AML cell-mediated T cell suppression of most SFR cases. To validate and extend these findings, we performed the T cell activation assay in an independent cohort of 50 AML cases representing all ELN risk groups. The ability of marrow derived CD4+ T cells to activate correlated strongly with ELN groups. Importantly, for the ELN intermediate patients, the immune activation assay stratified these patients in 2 groups with very different relapse free survival (RFS): the T cell "activators" had an RFS of 1200 days, while the "non-activators" had RFS of 146 days (Mantel-Cox Log-rank = 0.02). A multivariate analysis of covariates at diagnosis, including sex, age, ELN risk category, WBC count, bone marrow blast count at presentation, and mutation status (for DNMT3A, NPM1, FLT3, NRAS, WT1, TET2, CEBPA, PTPN11, IDH1, IDH2, RUNX1, RAD21, SMC1A, and SRSF2) identified none that were predictive of CD4 T cell activation status at presentation. Conclusions: These data strongly suggest that most AML cases have an immunosuppressive phenotype at presentation, mediated by inhibitory T cell receptors (e.g. LAG3) via ligands that are expressed by AML cells (e.g. MHC Class II proteins). The absence of this immunosuppressive phenotype was strongly correlated with favorable clinical outcomes with standard chemotherapy. The ability of CD4 T cells to be activated via the TCR in the presence of AML cells at presentation (which indirectly measures AML cell-mediated immunosuppression) is a novel biomarker for risk assessment that is currently not captured by any other well-recognized covariate (especially for ELN intermediate risk cases), and should be further evaluated for its predictive potential in prospective clinical trials. Disclosures Eisfeld: Karyopharm (spouse): Current Employment. Retting: BioLineRx Ltd.: Research Funding. Uy: GlaxoSmithKline: Consultancy; Agios: Consultancy; Novartis: Consultancy; Genentech: Consultancy; AbbVie: Consultancy; Macrogenics: Research Funding; Astellas: Honoraria, Speakers Bureau; Jazz: Consultancy. Spencer: Wugen, Inc.: Consultancy, Other: Stock options.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2021
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