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Biology subjects

Goldberg, A. D.

Publications and source records attributed to Goldberg, A. D..

4 recordsLinked to original sources

Single cell genotypic and phenotypic analysis of measurable residual disease in acute myeloid leukemia

Measurable residual disease (MRD), defined as the population of cancer cells which persists following therapy, serves as the critical reservoir for disease relapse in acute myeloid leukemia (AML) and other malignancies. Understanding the biology enabling MRD clones to resist therapy is necessary to guide the development of more effective curative treatments. Discriminating between residual leukemic clones, preleukemic clones and normal precursors remains a challenge with current MRD tools. Herein, we developed a single cell (sc) MRD assay by combining flow cytometric enrichment of the targeted precursor/blast population with integrated scDNA sequencing and immunophenotyping. Our scMRD assay shows high sensitivity of approximately 0.01%, deconvolutes clonal architecture and provides clone-specific immunophenotypic data. In summary, our scMRD assay enhances MRD detection and simultaneously illuminates the clonal architecture of clonal hematopoiesis/pre-leukemic and leukemic cells surviving AML therapy. Statement of significanceScMRD assay integrates mutation and immunophenotype at single cell resolution and therefore distinguishes clonal hematopoiesis/preleukemic vs. leukemic clones. This study serves as a framework for identifying high-risk MRD clones and improving our understanding of both the molecular drivers and vulnerabilities of therapy resistant AML clones.

pathology↗

Plasmacytoid dendritic cell expansion defines a distinct subset of RUNX1 mutated acute myeloid leukemia

Plasmacytoid dendritic cells (pDC) are the principal natural type I interferon producing dendritic cells. Neoplastic expansion of pDCs and pDC precursors leads to blastic plasmacytoid dendritic cell neoplasm (BPDCN) and clonal expansion of mature pDCs has been described in chronic myelomonocytic leukemia (CMML). The role of pDC expansion in acute myeloid leukemia (AML) is poorly studied. Here we characterize AML patients with pDC expansion (pDC-AML), which we observe in approximately 5% of AML. pDC-AML often possess crosslineage antigen expression and have adverse risk stratification with poor outcome. RUNX1 mutations are the most common somatic alterations in pDC-AML (>70%) and are much more common than in AML without PDC expansion. We demonstrate that pDCs are clonally related to, and originate from, leukemic blasts in pDC-AML. We further demonstrate that leukemic blasts from RUNX1-mutated AML upregulate a pDC transcriptional program, poising the cells towards pDC differentiation and expansion. Finally, tagraxofusp, a targeted therapy directed to CD123, reduces leukemic burden and eliminates pDCs in a patient-derived xenograft model. In conclusion, pDC-AML is characterized by a high frequency of RUNX1 mutations and increased expression of a pDC transcriptional program. CD123 targeting represents a potential treatment approach for pDC-AML.Competing Interest StatementConflict-of-interest disclosure: W.X. has received research support from Stemline Therapeutics. S.F.C. is a consultant for Imago Biosciences and has received honoraria from DAVA Oncology. A.D.G. served on advisory boards or as a consultant for Abbvie, Aptose, Celgene, Daiichi Sanyko, Genentech, received research funding from Abbvie, ADC Therapeutics, Aprea, AROG, Daiichi Sanyko, Pfizer, received Honoraria from Dava Oncology. R.K.R has received consulting fees from: Constellation, Incyte, Celgene, Promedior, CTI, Jazz Pharmaceuticals, Blueprint, Stemline, and research funding from Incyte, Constellation, and Stemline Therapeutics. M.S.T has received research funding from AbbVie, Cellerant, Orsenix, ADC Therapeutics, Biosight, Glycomimetics, Rafael Pharmaceuticals and Amgen. He also served on advisory Boards for AbbVie, BioLineRx, Daiichi-Sankyo, Orsenix, KAHR, Rigel, Nohla, Delta Fly Pharma, Tetraphase, Oncolyze, Jazz Pharma, Roche, Biosight and Novartis. He received royalties from UpToDate. R.L.L. is on the supervisory board of Qiagen and is a scientific advisor to Loxo (until 2019), Auron, Ajax, Mission Bio, Imago, C4 Therapeutics and Isoplexis, which each include an equity interest. He receives research support from and consulted for Celgene and Roche, he has received research support from Prelude Therapeutics, and he has consulted for Incyte, Novartis and Janssen. He has received honoraria from Lilly and Amgen for invited lectures and from Gilead for grant reviews.View Full Text

pathology↗

Leukemia cell of origin influences apoptotic priming and sensitivity to LSD1 inhibition

Previous studies have established that the cell of origin of oncogenic transformation is a determinant of therapeutic sensitivity. However, the mechanisms governing cell-of-origin-driven differences in therapeutic response have not been delineated. Leukemias initiating in hematopoietic stem cells (HSC) are less sensitive to cytotoxic chemotherapy and express high levels of the transcription factor Evi1 compared to leukemias derived from myeloid progenitors. Here, we compared drug sensitivity and expression profiles of murine and human leukemias initiated in either HSCs or myeloid progenitors to reveal a novel function for Evi1 in modulating p53 protein stability and activity. HSC-derived leukemias exhibit decreased apoptotic priming, attenuated p53 transcriptional output, and resistance to lysine-specific demethylase 1 inhibitors in addition to classical genotoxic stresses. p53 loss-of-function in Evi1low progenitor-derived leukemias induces resistance to LSD1 inhibition. By contrast, Evi1high leukemias are sensitized to LSD1 inhibition by the BH3 mimetic venetoclax, resulting in enhanced apoptosis and greater reductions in disease burden. Our findings demonstrate a cell-of-origin determined novel role for EVI1 in p53 wild-type cancers in reducing p53 function and provide a strategy to circumvent drug resistance in high-risk, chemoresistant EVI1high AML.

cancer biology↗

Single cell mutational profiling delineates clonal trajectories in myeloid malignancies

Myeloid malignancies, including acute myeloid leukemia (AML), arise from the proliferation and expansion of hematopoietic stem and progenitor cells which acquire somatic mutations. Bulk molecular profiling studies on patient samples have suggested that somatic mutations are obtained in a step-wise fashion, where mutant genes with high variant allele frequencies (VAFs) are proposed to occur early in disease development and mutations with lower VAFs are thought to be acquired later in disease progression1-3. Although bulk sequencing informs leukemia biology and prognostication, it cannot distinguish which mutations occur in the same clone(s), accurately measure clonal complexity and clone size, or offer definitive evidence of mutational order. To elucidate the clonal framework of myeloid malignancies, we performed single cell mutational profiling on 146 samples from 123 patients. We found AML is most commonly comprised of a small number of dominant clones, which in many cases harbor co-occurring mutations in epigenetic regulators. Conversely, mutations in signaling genes often occur more than once in distinct subclones consistent with increasing clonal diversity. We also used these data to map the clonal trajectory of each patient and found that specific mutation combinations (FLT3-ITD + NPM1c) synergize to promote clonal expansion and dominance. We combined cell surface protein expression with single cell mutational analysis to map somatic genotype and clonal architecture with immunophenotype. Our studies of clonal architecture at a single cell level provide novel insights into the pathogenesis of myeloid transformation and how clonal complexity contributes to disease progression.

cancer biology↗