Despite recent work linking mixed phenotype acute leukemia (MPAL) to certain genetic lesions, specific driver mutations remain undefined for a significant proportion of patients and no genetic subtype is predictive of clinical outcomes. Moreover, therapeutic strategy for MPAL remains unclear, and prognosis is overall poor. We performed multiomic single cell profiling of 14 newly diagnosed adult MPAL patients to characterize the inter- and intra-tumoral transcriptional, immunophenotypic, and genetic landscapes of MPAL.
View Article and Find Full Text PDFMutations in five canonical Ras pathway genes (NF1, NRAS, KRAS, PTPN11 and CBL) are detected in nearly 90% of patients with juvenile myelomonocytic leukemia (JMML), a frequently fatal malignant neoplasm of early childhood. In this report, we describe seven patients diagnosed with SH2B3-mutated JMML, including five patients who were found to have initiating, loss-of-function mutations in the gene. SH2B3 encodes the adaptor protein LNK, a negative regulator of normal hematopoiesis upstream of the Ras pathway.
View Article and Find Full Text PDFInt J Hematol
November 2024
Fms-like tyrosine kinase 3 (FLT3) is the most frequently mutated gene in acute myeloid leukemia (AML). Modern targeting of FLT3 with inhibitors has improved clinical outcomes and FLT3 inhibitors have been incorporated into the treatment of AML in all phases of the disease, including the upfront, relapsed/refractory and maintenance settings. This review will discuss the current understanding of FLT3 biology, the clinical use of FLT3 inhibitors, resistance mechanisms and emerging combination treatment strategies.
View Article and Find Full Text PDFMutations in the receptor tyrosine kinases (RTKs) FLT3 and KIT are frequent and associated with poor outcomes in acute myeloid leukemia (AML). Although selective FLT3 inhibitors (FLT3i) are clinically effective, remissions are short-lived due to secondary resistance characterized by acquired mutations constitutively activating the RAS/MAPK pathway. Hereby, we report the pre-clinical efficacy of co-targeting SHP2, a critical node in MAPK signaling, and BCL2 in RTK-driven AML.
View Article and Find Full Text PDFIntroduction: Allogeneic hematopoietic cell transplantation (alloHCT) is increasingly offered to older adults, and its potential impact on cognition in this population is understudied. This work aims to evaluate the ability of cancer-specific geriatric assessments (cGA) and a global frailty index based on accumulation of deficits identified in the cGA to predict the risk of cognitive decline after alloHCT in older adults.
Materials And Methods: AlloHCT recipients aged 50 years or older completed a cGA, including a cognitive evaluation by the Blessed Orientation Memory Concentration (BOMC) test, at baseline prior to alloHCT and then at 3, 6, and 12 months after transplant.
Mixed phenotype acute leukemia (MPAL) is a leukemia whose biologic drivers are poorly understood, therapeutic strategy remains unclear, and prognosis is poor. We performed multiomic single cell (SC) profiling of 14 newly diagnosed adult MPAL patients to characterize the immunophenotypic, genetic, and transcriptional landscapes of MPAL. We show that neither genetic profile nor transcriptome reliably correlate with specific MPAL immunophenotypes.
View Article and Find Full Text PDFCurrent single-cell RNA-sequencing approaches have limitations that stem from the microfluidic devices or fluid handling steps required for sample processing. We develop a method that does not require specialized microfluidic devices, expertise or hardware. Our approach is based on particle-templated emulsification, which allows single-cell encapsulation and barcoding of cDNA in uniform droplet emulsions with only a vortexer.
View Article and Find Full Text PDFPurpose: The FMS-related tyrosine kinase 3 (FLT3) inhibitor gilteritinib is standard therapy for relapsed/refractory -mutated () acute myeloid leukemia (AML) but seldom reduces burden or induces sustained efficacy. Gilteritinib combines synergistically with the BCL-2 inhibitor venetoclax in preclinical models of AML.
Methods: This phase Ib open-label, dose-escalation/dose-expansion study (ClinicalTrials.
Small-molecule FLT3 inhibitors have recently improved clinical outcomes for patients with FLT3-mutant acute myeloid leukemia (AML) after many years of development, but resistance remains an important clinical problem. FF-10101 is the first irreversible, covalent inhibitor of FLT3 which has previously shown activity against FLT3 tyrosine kinase inhibitor resistance-causing FLT3 F691L and D835 mutations. We report that FF-10101 is also active against an expanded panel of clinically identified FLT3 mutations associated with resistance to other FLT3 inhibitors.
View Article and Find Full Text PDFAs allogeneic hematopoietic cell transplantation (alloHCT) is increasingly offered to older adults, geriatric assessment (GA) has been identified as a useful tool for predicting outcomes, particularly functional status. However, very few studies have examined the longitudinal change in GA measures in the post-alloHCT period. The objectives of this study were to describe the longitudinal change in GA and quality of life (QoL) measures after alloHCT and to identify predictors of greater functional decline post-transplantation.
View Article and Find Full Text PDFThe phase 3 Study of ASP2215 Versus Salvage Chemotherapy in Patients With Relapsed or Refractory Acute Myeloid Leukemia (AML) With FMS-like Tyrosine Kinase (FLT3) Mutation (ADMIRAL) trial demonstrated the superiority of the FLT3 inhibitor, gilteritinib, to salvage chemotherapy (SC) in patients with FLT3-mutated relapsed or refractory (R/R) AML. Baseline comutations, FLT3-internal tandem duplication (ITD) allelic ratio and length, and treatment-emergent mutations were analyzed in patients in the ADMIRAL trial. Baseline comutations were grouped according to gene subgroups (DNA methylation/hydroxymethylation, transcription, chromatin-spliceosome, receptor tyrosine kinase-Ras signaling, TP53-aneuploidy, NPM1, DNMT3A, DNMT3A/NPM1, WT-1, and IDH1/IDH2).
View Article and Find Full Text PDFPurpose: Biomarkers of response and resistance to FLT3 tyrosine kinase inhibitors (TKI) are still emerging, and optimal clinical combinations remain unclear. The purpose of this study is to identify co-occurring mutations that influence clinical response to the novel FLT3 inhibitor pexidartinib (PLX3397).
Experimental Design: We performed targeted sequencing of pretreatment blasts from 29 patients with internal tandem duplication (ITD) mutations treated on the phase I/II trial of pexidartinib in relapsed/refractory -ITD+ acute myeloid leukemia (AML).
Studies of acute myeloid leukemia rely on DNA sequencing and immunophenotyping by flow cytometry as primary tools for disease characterization. However, leukemia tumor heterogeneity complicates integration of DNA variants and immunophenotypes from separate measurements. Here we introduce DAb-seq, a technology for simultaneous capture of DNA genotype and cell surface phenotype from single cells at high throughput, enabling direct profiling of proteogenomic states in tens of thousands of cells.
View Article and Find Full Text PDFSingle-cell sequencing exposes previously unmeasurable complexity of tumor heterogeneity and clonal evolution on quizartinib. Single-cell sequencing reveals on- and off-target mechanisms of resistance to quizartinib, which can preexist therapy.
View Article and Find Full Text PDFNeutralizing antibody function provides a foundation for the efficacy of vaccines and therapies. Here, using a robust in vitro Ebola virus (EBOV) pseudo-particle infection assay and a well-defined set of solid-phase assays, we describe a wide spectrum of antibody responses in a cohort of healthy survivors of the Sierra Leone EBOV outbreak of 2013-2016. Pseudo-particle virus-neutralizing antibodies correlated with total anti-EBOV reactivity and neutralizing antibodies against live EBOV.
View Article and Find Full Text PDFThe FLT3 receptor is overexpressed on the majority of acute myeloid leukemia (AML) blasts. Mutations in are the most common genetic alteration in AML, identified in approximately one third of newly diagnosed patients. internal tandem duplication mutations (ITD) are associated with increased relapse and inferior overall survival.
View Article and Find Full Text PDFLancet
December 2021
Background: Older adults (aged ≥70 years) are at increased risk of severe disease and death if they develop COVID-19 and are therefore a priority for immunisation should an efficacious vaccine be developed. Immunogenicity of vaccines is often worse in older adults as a result of immunosenescence. We have reported the immunogenicity of a novel chimpanzee adenovirus-vectored vaccine, ChAdOx1 nCoV-19 (AZD1222), in young adults, and now describe the safety and immunogenicity of this vaccine in a wider range of participants, including adults aged 70 years and older.
View Article and Find Full Text PDFMutations in the FLT3 receptor tyrosine kinase are the most frequently found mutations in acute myeloid leukemia (AML). Patients with FLT3 internal tandem duplication (ITD) mutations have poor prognoses. The approved FLT3 tyrosine kinase inhibitors (TKIs) midostaurin and gilteritinib improve survival in AML with FLT3 mutations.
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