-
Acta Haematologica 2024Acute myeloid leukemia (AML) is a biologically heterogenous disease arising in clonally proliferating hematopoietic stem cells. Sequential acquisition of mutations leads... (Review)
Review
BACKGROUND
Acute myeloid leukemia (AML) is a biologically heterogenous disease arising in clonally proliferating hematopoietic stem cells. Sequential acquisition of mutations leads to expanded proliferation of clonal myeloid progenitors and failure of differentiation, leading to fulminant AML.
SUMMARY
Here, we review the pathophysiology of AML with a focus on factors predisposing to AML development, including prior chemo- and radiation therapy, environmental factors, and germline predisposition.
KEY MESSAGE
Increasing genomic characterization of AML and insight into mechanisms of its development will be critical to improvement in AML prognostication and therapy.
Topics: Humans; Hematopoietic Stem Cells; Leukemia, Myeloid, Acute; Cell Differentiation; Genotype
PubMed: 38228114
DOI: 10.1159/000536152 -
American Journal of Hematology Sep 2023The nucleophosmin (NPM1) gene encodes for a multifunctional chaperone protein that is localized in the nucleolus but continuously shuttles between the nucleus and... (Review)
Review
The nucleophosmin (NPM1) gene encodes for a multifunctional chaperone protein that is localized in the nucleolus but continuously shuttles between the nucleus and cytoplasm. NPM1 mutations occur in about one-third of AML, are AML-specific, usually involve exon 12 and are frequently associated with FLT3-ITD, DNMT3A, TET2, and IDH1/2 mutations. Because of its unique molecular and clinico-pathological features, NPM1-mutated AML is regarded as a distinct leukemia entity in both the International Consensus Classification (ICC) and the 5th edition of the World Health Organization (WHO) classification of myeloid neoplasms. All NPM1 mutations generate leukemic mutants that are aberrantly exported in the cytoplasm of the leukemic cells and are relevant to the pathogenesis of the disease. Here, we focus on recently identified functions of the NPM1 mutant at chromatin level and its relevance in driving HOX/MEIS gene expression. We also discuss yet controversial issues of the ICC/WHO classifications, including the biological and clinical significance of therapy-related NPM1-mutated AML and the relevance of blasts percentage in defining NPM1-mutated AML. Finally, we address the impact of new targeted therapies in NPM1-mutated AML with focus on CAR T cells directed against NPM1/HLA neoepitopes, as well as XPO1 and menin inhibitors.
Topics: Humans; Nucleophosmin; Nuclear Proteins; Leukemia, Myeloid, Acute; Mutation; Cytoplasm
PubMed: 37317978
DOI: 10.1002/ajh.26989 -
Annals of Hematology Aug 2023Myeloid sarcoma (MS) is a distinct entity among myeloid neoplasms defined as a tumour mass of myeloid blasts occurring at an anatomical site other than the bone marrow,... (Review)
Review
Myeloid sarcoma (MS) is a distinct entity among myeloid neoplasms defined as a tumour mass of myeloid blasts occurring at an anatomical site other than the bone marrow, in most cases concomitant with acute myeloid leukaemia (AML), rarely without bone marrow involvement. MS may also represent the blast phase of chronic myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS). However, the clinical and molecular heterogeneity of AML, as highlighted by the 2022 World Health Organization (WHO) and International Consensus (ICC) classifications, indirectly define MS more as a set of heterogeneous and proteiform diseases, rather than a homogeneous single entity. Diagnosis is challenging and relies mainly on histopathology, immunohistochemistry, and imaging. Molecular and cytogenetic analysis of MS tissue, particularly in isolated cases, should be performed to refine the diagnosis, and thus assign prognosis guiding treatment decisions. If feasible, systemic therapies used in AML remission induction should be employed, even in isolated MS. Role and type of consolidation therapy are not univocally acknowledged, and systemic therapies, radiotherapy, or allogeneic hematopoietic stem cell transplantation (allo-HSCT) should be considered. In the present review, we discuss recent information on MS, focusing on diagnosis, molecular findings, and treatments also considering targetable mutations by recently approved AML drugs.
Topics: Humans; Sarcoma, Myeloid; Leukemia, Myeloid, Acute; Myelodysplastic Syndromes; Myeloproliferative Disorders; Hematopoietic Stem Cell Transplantation
PubMed: 37286874
DOI: 10.1007/s00277-023-05288-1 -
Haematologica Sep 2023Although outcomes of children and adolescents with newly diagnosed acute myeloid leukemia (AML) have improved significantly over the past two decades, more than... (Review)
Review
Although outcomes of children and adolescents with newly diagnosed acute myeloid leukemia (AML) have improved significantly over the past two decades, more than one-third of patients continue to relapse and experience suboptimal long-term outcomes. Given the small numbers of patients with relapsed AML and historical logistical barriers to international collaboration including poor trial funding and drug availability, the management of AML relapse has varied among pediatric oncology cooperative groups with several salvage regimens utilized and a lack of universally defined response criteria. The landscape of relapsed pediatric AML treatment is changing rapidly, however, as the international AML community harnesses collective knowledge and resources to characterize the genetic and immunophenotypic heterogeneity of relapsed disease, identify biological targets of interest within specific AML subtypes, develop new precision medicine approaches for collaborative investigation in early-phase clinical trials, and tackle challenges of universal drug access across the globe. This review provides a comprehensive overview of progress achieved to date in the treatment of pediatric patients with relapsed AML and highlights modern, state-of-the-art therapeutic approaches under active and emerging clinical investigation that have been facilitated by international collaboration among academic pediatric oncologists, laboratory scientists, regulatory agencies, pharmaceutical partners, cancer research sponsors, and patient advocates.
Topics: Adolescent; Humans; Child; Treatment Outcome; Leukemia, Myeloid, Acute; Recurrence
PubMed: 36861399
DOI: 10.3324/haematol.2022.281106 -
Blood Cancer Discovery Jan 2024NPM1-mutated acute myeloid leukemia (AML) represents the largest molecular subgroup of adult AML. NPM1-mutated AML is recognizable by molecular techniques and... (Review)
Review
UNLABELLED
NPM1-mutated acute myeloid leukemia (AML) represents the largest molecular subgroup of adult AML. NPM1-mutated AML is recognizable by molecular techniques and immunohistochemistry, which, when combined, can solve difficult diagnostic problems (including identification of myeloid sarcoma and NPM1 mutations outside exon 12). According to updated 2022 European LeukemiaNet (ELN) guidelines, determining the mutational status of NPM1 (and FLT3) is a mandatory step for the genetic-based risk stratification of AML. Monitoring of measurable residual disease (MRD) by qRT-PCR, combined with ELN risk stratification, can guide therapeutic decisions at the post-remission stage. Here, we review the criteria for appropriate diagnosis and molecular monitoring of NPM1-mutated AML.
SIGNIFICANCE
NPM1-mutated AML represents a distinct entity in the 2022 International Consensus Classification and 5th edition of World Health Organization classifications of myeloid neoplasms. The correct diagnosis of NPM1-mutated AML and its distinction from other AML entities is extremely important because it has clinical implications for the management of AML patients, such as genetic-based risk stratification according to 2022 ELN. Monitoring of MRD by qRT-PCR, combined with ELN risk stratification, can guide therapeutic decisions at the post-remission stage, e.g., whether or not to perform allogeneic hematopoietic stem cell transplantation.
Topics: Adult; Humans; Nuclear Proteins; Nucleophosmin; Leukemia, Myeloid, Acute; Mutation; Risk Factors
PubMed: 37917833
DOI: 10.1158/2643-3230.BCD-23-0144 -
Blood Jul 2023Acute myeloid leukemia (AML) is an aggressive hematological malignancy. Nearly 50% of patients who receive the most intensive treatment inevitably experience disease...
Acute myeloid leukemia (AML) is an aggressive hematological malignancy. Nearly 50% of patients who receive the most intensive treatment inevitably experience disease relapse, likely resulting from the persistence of drug-resistant leukemia stem cells (LSCs). AML cells, especially LSCs, are highly dependent on mitochondrial oxidative phosphorylation (OXPHOS) for survival, but the mechanism involved in OXPHOS hyperactivity is unclear, and a noncytotoxic strategy to inhibit OXPHOS is lacking. To our knowledge, this study is the first to demonstrate that ZDHHC21 palmitoyltransferase serves as a key regulator of OXPHOS hyperactivity in AML cells. The depletion/inhibition of ZDHHC21 effectively induced myeloid differentiation and weakened stemness potential by inhibiting OXPHOS in AML cells. Interestingly, FMS-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD)-mutated AML cells expressed significantly higher levels of ZDHHC21 and exhibited better sensitivity to ZDHHC21 inhibition. Mechanistically, ZDHHC21 specifically catalyzed the palmitoylation of mitochondrial adenylate kinase 2 (AK2) and further activated OXPHOS in leukemic blasts. Inhibition of ZDHHC21 arrested the in vivo growth of AML cells and extended the survival of mice inoculated with AML cell lines and patient derived xenograft AML blasts. Moreover, targeting ZDHHC21 to suppress OXPHOS markedly eradicated AML blasts and enhanced chemotherapy efficacy in relapsed/refractory leukemia. Together, these findings not only uncover a new biological function of palmitoyltransferase ZDHHC21 in regulating AML OXPHOS but also indicate that ZDHHC21 inhibition is a promising therapeutic regimen for patients with AML, especially relapsed/refractory leukemia.
Topics: Animals; Humans; Mice; Cell Differentiation; fms-Like Tyrosine Kinase 3; Leukemia, Myeloid, Acute; Mutation; Oxidative Phosphorylation; Protein Kinase Inhibitors
PubMed: 37216691
DOI: 10.1182/blood.2022019056 -
Pathobiology : Journal of... 2024Disease progression in myelodysplastic syndromes (MDS), myelodysplastic-myeloproliferative neoplasms (MDS/MPN), and myeloproliferative neoplasms (MPN), altogether... (Review)
Review
Disease progression in myelodysplastic syndromes (MDS), myelodysplastic-myeloproliferative neoplasms (MDS/MPN), and myeloproliferative neoplasms (MPN), altogether referred to as myeloid neoplasms (MN), is a major source of mortality. Apart from transformation to acute myeloid leukemia, the clinical progression of MN is mostly due to the overgrowth of pre-existing hematopoiesis by the MN without an additional transforming event. Still, MN may evolve along other recurrent yet less well-known scenarios: (1) acquisition of MPN features in MDS or (2) MDS features in MPN, (3) progressive myelofibrosis (MF), (4) acquisition of chronic myelomonocytic leukemia (CMML)-like characteristics in MPN or MDS, (5) development of myeloid sarcoma (MS), (6) lymphoblastic (LB) transformation, (7) histiocytic/dendritic outgrowths. These MN-transformation types exhibit a propensity for extramedullary sites (e.g., skin, lymph nodes, liver), highlighting the importance of lesional biopsies in diagnosis. Gain of distinct mutations/mutational patterns seems to be causative or at least accompanying several of the above-mentioned scenarios. MDS developing MPN features often acquire MPN driver mutations (usually JAK2), and MF. Conversely, MPN gaining MDS features develop, e.g., ASXL1, IDH1/2, SF3B1, and/or SRSF2 mutations. Mutations of RAS-genes are often detected in CMML-like MPN progression. MS ex MN is characterized by complex karyotypes, FLT3 and/or NPM1 mutations, and often monoblastic phenotype. MN with LB transformation is associated with secondary genetic events linked to lineage reprogramming leading to the deregulation of ETV6, IKZF1, PAX5, PU.1, and RUNX1. Finally, the acquisition of MAPK-pathway gene mutations may shape MN toward histiocytic differentiation. Awareness of all these less well-known MN-progression types is important to guide optimal individual patient management.
Topics: Humans; Granulocyte Precursor Cells; Myeloproliferative Disorders; Myelodysplastic Syndromes; Mutation; Myelodysplastic-Myeloproliferative Diseases; Leukemia, Myeloid, Acute
PubMed: 37232015
DOI: 10.1159/000530940 -
Blood Advances Aug 2023The discovery of isocitrate dehydrogenase 1 (IDH1) mutations in acute myeloid leukemia (AML) and the resounding success of molecularly targeted therapies in related... (Review)
Review
The discovery of isocitrate dehydrogenase 1 (IDH1) mutations in acute myeloid leukemia (AML) and the resounding success of molecularly targeted therapies in related myeloid malignancies swiftly prompted the development of IDH1mut inhibitors. Olutasidenib (formerly known as FT-2102) is an orally administered novel IDH1mut inhibitor that entered clinical development in 2016, proceeded briskly through the developmental process, and was granted regular approval to treat patients with R/R IDH1mut AML on 1 December 2022. Single agent olutasidenib, a potent and selective IDH1mut inhibitor, demonstrated highly durable remission rates along with meaningful outcomes, such as transfusion independence, in patients with R/R IDH1mut AML. This review will examine the preclinical and clinical development and the positioning of olutasidenib in the IDH1mut AML treatment landscape.
Topics: Humans; Isocitrate Dehydrogenase; Pyridines; Quinolines; Leukemia, Myeloid, Acute
PubMed: 37196640
DOI: 10.1182/bloodadvances.2023009854 -
Journal of Experimental & Clinical... Dec 2023Myeloid cells (granulocytes and monocytes/macrophages) play an important role in neuroblastoma. By inducing a complex immunosuppressive network, myeloid cells pose a... (Review)
Review
Myeloid cells (granulocytes and monocytes/macrophages) play an important role in neuroblastoma. By inducing a complex immunosuppressive network, myeloid cells pose a challenge for the adaptive immune system to eliminate tumor cells, especially in high-risk neuroblastoma. This review first summarizes the pro- and anti-tumorigenic functions of myeloid cells, including granulocytes, monocytes, macrophages, and myeloid-derived suppressor cells (MDSC) during the development and progression of neuroblastoma. Secondly, we discuss how myeloid cells are engaged in the current treatment regimen and explore novel strategies to target these cells in neuroblastoma. These strategies include: (1) engaging myeloid cells as effector cells, (2) ablating myeloid cells or blocking the recruitment of myeloid cells to the tumor microenvironment and (3) reprogramming myeloid cells. Here we describe that despite their immunosuppressive traits, tumor-associated myeloid cells can still be engaged as effector cells, which is clear in anti-GD2 immunotherapy. However, their full potential is not yet reached, and myeloid cell engagement can be enhanced, for example by targeting the CD47/SIRPα axis. Though depletion of myeloid cells or blocking myeloid cell infiltration has been proven effective, this strategy also depletes possible effector cells for immunotherapy from the tumor microenvironment. Therefore, reprogramming of suppressive myeloid cells might be the optimal strategy, which reverses immunosuppressive traits, preserves myeloid cells as effectors of immunotherapy, and subsequently reactivates tumor-infiltrating T cells.
Topics: Humans; Neuroblastoma; Neoplasms; Myeloid Cells; Immunotherapy; Myeloid-Derived Suppressor Cells; Macrophages; Tumor Microenvironment
PubMed: 38087370
DOI: 10.1186/s13046-023-02913-9 -
International Journal of Laboratory... Aug 2023The proliferation of new molecular technologies in recent years has greatly advanced our knowledge of the genetics that underlie hematologic cancers. Particularly, with... (Review)
Review
The proliferation of new molecular technologies in recent years has greatly advanced our knowledge of the genetics that underlie hematologic cancers. Particularly, with the advent and wide-implementation of next-generation sequencing (NGS), a host of somatic (and some germline) gene mutations have been identified as significant in the classification, prognostication, and treatment of the spectrum of myeloid neoplasms. These driver and disease modifier mutations now play a prominent role in the updated international diagnostic guidelines of acute myeloid leukemia (AML), myelodysplastic syndromes/neoplasms (MDS), and myeloproliferative neoplasms (MPN). As high-throughput technologies such as NGS increasingly become standard in the genetic evaluation of myeloid disorders, it is critical that clinicians understand the clinical relevance of these mutations in order to further personalize patient care. In this review we discuss some of the most essential somatic and cytogenetic findings.
Topics: Humans; Myeloproliferative Disorders; Myelodysplastic Syndromes; Leukemia, Myeloid, Acute; Mutation; Hematologic Neoplasms
PubMed: 37345257
DOI: 10.1111/ijlh.14118