scholarly journals The Oncogenic Role of N6-Methyladenosine Reader Protein IGF2BP3 in Acute Myeloid Leukemia

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1334-1334
Author(s):  
Huilin Huang ◽  
Hengyou Weng ◽  
Mingli Sun ◽  
Huizhe Wu ◽  
Zhenhua Chen ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Cell Viability ◽  
Progenitor Cells ◽  
Myeloid Leukemia ◽  
Poor Prognosis ◽  
Expression Level ◽  
Wild Type ◽  
Hematopoietic Stem ◽  
Acute Myeloid

Abstract RNA N6-Methyladenosine (m6A) modification is an abundant modification of internal mRNAs in eukaryotes and some viruses, which is dynamically and reversibly fine-tuned during normal and pathological bioprocesses. Recent studies have shown that m6A methyltransferases, METTL3 and METTL14, play important roles in maintaining self-renewal capacity of hematopoietic stem/progenitor cells (HSPCs) and promoting acute myeloid leukemia (AML) development (Barbiori et al., Nature, 2017; Vu et al., Nature Method, 2017; Weng et al. Cell Stem Cell, 2018). The m6A demethylase, FTO, was also shown to promote leukemic cell transformation and leukemogenesis in various type of AML (Li et al., Cancer Cell, 2017). However, little is known about the functions of m6A readers in malignant hematopoiesis. We recently reported that Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) is an specific m6A binding protein, which recognize m6A transcripts through the K Homology (KH) domains to stabilize and promote translation of its target mRNAs (Huang et al., Nature Cell Biology, 2018). In analysis of TCGA AML dataset (n=157), we found that a higher expression level of IGF2BP3 is significantly associated with a poor prognosis in AML patients (p<0.001; Median overall survival: IGF2BP3-High vs. IGF2BP3-Low = 11 months vs. 31 months). In addition, we analyzed our in-house microarray profiling of 113 AML patient samples and found that IGF2BP3 is highly expressed in mononuclear cells (MNC) from MLL-rearranged leukemia patients as compared to those from healthy donors (p<0.05) or non-MLL-rearranged leukemic patients (p<0.001). Consistent with the overexpression of IGF2BP3 in human MLL-rearranged AML, MLL-AF9 or MLL-AF10 transformed mouse hematopoietic stem/progenitor cells (HSPCs; herein mouse lineage negative (Lin-) bone marrow cells) showed a >10 fold increase in expression level of Igf2bp3, compare to the non-transformed counterpart HSPCs. Furthermore, in analysis of 562 samples from adult patients with AML (GSE37642), we found that within cytogenetically normal human AML, patients carrying FLT3-ITD mutation showed a significantly higher level of IGF2BP3 expression than those without FLT3-ITD mutation (p<0.01). To investigate the potential oncogenic role of IGF2BP3 in AML, we cotransduced mouse Lin- BM progenitor cells with MLL-AF9 and three individual shRNAs targeting Igf2bp3 or a scrambled control shRNA and performed colony-forming/replating assays. Knockdown of Igf2bp3 significantly (p<0.05) reduced the colony-forming capacity of MLL-AF9-transduced HSPCs to 20-50% of that of the control group. Conversely, forced expression of wild-type IGF2BP3 significantly (p<0.05) promoted colony formation of MLL-AF9-transduced Lin- BM progenitor cells. Such promotion was almost completely impaired when KH3-4 domain of IGF2BP3 was mutated or when Mettl14 was depleted, suggesting that IGF2BP3 exerts its oncogenic function as an m6A reader through an m6A-dependent mechanism. We further used human leukemia cell lines to investigate the function of IGF2BP3 in human AML cells. Silencing of IGF2BP3 by two shRNAs significantly inhibited cell viability and proliferation and induced cell apoptosis (p<0.01) in MonoMac6 AML cell line which harbors the t(9;11) translocation. In Molm13 and MV4-11 AML cells which are heterozygous and homozygous for the FLT3-ITD mutation, respectively, a further decrease of cell viability and increase of apoptotic cells upon IGF2BP3 knockdown was observed compared to MonoMac6 with wild-type FLT3. Mechanically, through cross-linking immunoprecipitation sequencing (CLIP-seq), we showed that IGF2BP3 targets mRNAs in cell cycle, DNA replication and protein synthesis pathways. Taken together, these results demonstrated the oncogenic role of the new m6A reader protein IGF2BP3 in AML. Given the fact that expression of IGF2BP3 correlates with an overall poor prognosis in AML, IGF2BP3 is likely a promising therapeutic target for AML treatment. Disclosures No relevant conflicts of interest to declare.

Alternative polyadenylation dysregulation contributes to the differentiation block of acute myeloid leukemia

Blood ◽  
2021 ◽  
Author(s):  
Amanda G Davis ◽  
Daniel T. Johnson ◽  
Dinghai Zheng ◽  
Ruijia Wang ◽  
Nathan D. Jayne ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Alternative Polyadenylation ◽  
Hematopoietic Stem ◽  
Global Trends ◽  
Protein Levels ◽  
Mtorc1 Signaling ◽  
Differentiation Block ◽  
Acute Myeloid

Post-transcriptional regulation has emerged as a driver for leukemia development and an avenue for therapeutic targeting. Among post-transcriptional processes, alternative polyadenylation (APA) is globally dysregulated across cancer types. However, limited studies have focused on the prevalence and role of APA in myeloid leukemia. Furthermore, it is poorly understood how altered poly(A) site (PAS) usage of individual genes contributes to malignancy or whether targeting global APA patterns might alter oncogenic potential. In this study, we examined global APA dysregulation in acute myeloid leukemia (AML) patients by performing 3' Region Extraction And Deep Sequencing (3'READS) on a subset of AML patient samples along with healthy hematopoietic stem and progenitor cells (HSPCs) and by analyzing publicly available data from a broad AML patient cohort. We show that patient cells exhibit global 3' untranslated region (UTR) shortening and coding sequence (CDS) lengthening due to differences in PAS usage. Among APA regulators, expression of FIP1L1, one of the core cleavage and polyadenylation factors, correlated with the degree of APA dysregulation in our 3'READS dataset. Targeting global APA by FIP1L1 knockdown reversed the global trends seen in patients. Importantly, FIP1L1 knockdown induced differentiation of t(8;21) cells by promoting 3'UTR lengthening and downregulation of the fusion oncoprotein AML1-ETO. In non-t(8;21) cells, FIP1L1 knockdown also promoted differentiation by attenuating mTORC1 signaling and reducing MYC protein levels. Our study provides mechanistic insights into the role of APA in AML pathogenesis and indicates that targeting global APA patterns can overcome the differentiation block of AML patients.

scholarly journals CD70/CD27 signaling promotes blast stemness and is a viable therapeutic target in acute myeloid leukemia

2016 ◽  
Vol 214 (2) ◽  
pp. 359-380 ◽  
Author(s):  
Carsten Riether ◽  
Christian M. Schürch ◽  
Elias D. Bührer ◽  
Magdalena Hinterbrandner ◽  
Anne-Laure Huguenin ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Stem Cell ◽  
Progenitor Cells ◽  
Myeloid Leukemia ◽  
Hematopoietic Stem ◽  
Cell Divisions ◽  
Cell Gene ◽  
Stem Cell Gene ◽  
Acute Myeloid

Aberrant proliferation, symmetric self-renewal, increased survival, and defective differentiation of malignant blasts are key oncogenic drivers in acute myeloid leukemia (AML). Stem cell gene signatures predict poor prognosis in AML patients; however, with few exceptions, these deregulated molecular pathways cannot be targeted therapeutically. In this study, we demonstrate that the TNF superfamily ligand–receptor pair CD70/CD27 is expressed on AML blasts and AML stem/progenitor cells. CD70/CD27 signaling in AML cells activates stem cell gene expression programs, including the Wnt pathway, and promotes symmetric cell divisions and proliferation. Soluble CD27, reflecting the extent of CD70/CD27 interactions in vivo, was significantly elevated in the sera of newly diagnosed AML patients and is a strong independent negative prognostic biomarker for overall survival. Blocking the CD70/CD27 interaction by mAb induced asymmetric cell divisions and differentiation in AML blasts and AML stem/progenitor cells, inhibited cell growth and colony formation, and significantly prolonged survival in murine AML xenografts. Importantly, hematopoietic stem/progenitor cells from healthy BM donors express neither CD70 nor CD27 and were unaffected by blocking mAb treatment. Therefore, targeting CD70/CD27 signaling represents a promising therapeutic strategy for AML.

scholarly journals Gpr44 Mediates the Selenium-Dependent Anti-Leukemic Effect in Acute Myeloid Leukemia

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1835-1835
Author(s):  
Fenghua Qian ◽  
Fenghua Qian ◽  
Diwakar Tukaramrao ◽  
Jiayan Zhou ◽  
Nicole Palmiero ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Acute Myeloid Leukemia ◽  
Murine Model ◽  
Myeloid Leukemia ◽  
Hematopoietic Stem ◽  
Cell Counts ◽  
Pparγ Agonist ◽  
Acute Myeloid

Abstract Objectives The relapse of acute myeloid leukemia (AML) remains a significant concern due to persistent leukemia stem cells (LSCs) that are not targeted by existing therapies. LSCs show sensitivity to endogenous cyclopentenone prostaglandin J (CyPG) metabolites that are increased by dietary trace element selenium (Se), which is significantly decreased in AML patients. We investigated the anti-leukemic effect of Se supplementation in AML via mechanisms involving the activation of the membrane-bound G-protein coupled receptor 44 (Gpr44) and the intracellular receptor, peroxisome proliferator-activated receptor gamma (PPARγ), by endogenous CyPGs. Methods A murine model of AML generated by transplantation of hematopoietic stem cells (HSCs- WT or Gpr44−/−) expressing human MLL-AF9 fusion oncoprotein, in the following experiments: To investigate the effect of Se supplementation on the outcome of AML, donor mice were maintained on either Se-adequate (Se-A; 0.08–0.1 ppm Se) or Se-supplemented (Se-S; 0.4 ppm Se) diets. Complete cell counts in peripheral blood were analyzed by hemavet. LSCs in bone marrow and spleen were analyzed by flow cytometry. To determine the role of Gpr44 activation in AML, mice were treated with Gpr44 agonists, CyPGs. LSCs in bone marrow and spleen were analyzed. Mice transplanted with Gpr44−/- AML cells were compared with mice transplanted with wild type AML cells and the progression of the disease was followed as above. To determine the role of PPARγ activation in AML, PPARγ agonist (Rosiglitazone, 6 mg/kg, i.p, 14 d) and antagonist (GW9662, 1 mg/kg, i.p. once every other day, 7 injections) were applied to Se-S mice transplanted with Gpr44−/- AML cells and disease progression was followed. Results Se supplementation at supraphysiological levels alleviated the disease via the elimination of LSCs in a murine model of AML. CyPGs induced by Se supplementation mediate the apoptosis in LSCs via the activation of Gpr44 and PPARγ. Conclusions Endogenous CyPGs produced upon supplementation with Se at supraphysiological levels improved the outcome of AML by targeting LSCs to apoptosis via the activation of two receptors, Gpr44 and PPARg. Funding Sources NIH DK 07,7152; CA 175,576; CA 162,665. Office of Dietary Supplements, USDA Hatch funds PEN04605, Accession # 1,010,021 (KSP, RFP).

scholarly journals Human bone marrow depleted of CD33-positive cells mediates delayed but durable reconstitution of hematopoiesis: clinical trial of MY9 monoclonal antibody-purged autografts for the treatment of acute myeloid leukemia

Blood ◽  
1992 ◽  
Vol 79 (9) ◽  
pp. 2229-2236 ◽  
Author(s):  
MJ Robertson ◽  
RJ Soiffer ◽  
AS Freedman ◽  
SL Rabinowe ◽  
KC Anderson ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Bone Marrow ◽  
Acute Myeloid Leukemia ◽  
Progenitor Cells ◽  
Myeloid Leukemia ◽  
Red Blood Cell Transfusion ◽  
Hematopoietic Stem ◽  
Myeloid Progenitor ◽  
Myeloid Progenitor Cells ◽  
Acute Myeloid

Abstract The CD33 antigen, identified by murine monoclonal antibody anti-MY9, is expressed by clonogenic leukemic cells from almost all patients with acute myeloid leukemia; it is also expressed by normal myeloid progenitor cells. Twelve consecutive patients with de novo acute myeloid leukemia received myeloablative therapy followed by infusion of autologous marrow previously treated in vitro with anti-MY9 and complement. Anti-MY9 and complement treatment eliminated virtually all committed myeloid progenitors (colony-forming unit granulocyte- macrophage) from the autografts. Nevertheless, in the absence of early relapse of leukemia, all patients showed durable trilineage engraftment. The median interval post bone marrow transplantation (BMT) required to achieve an absolute neutrophil count greater than 500/microL was 43 days (range, 16 to 75), to achieve a platelet count greater than 20,000/microL without transfusion was 92 days (range, 35 to 679), and to achieve red blood cell transfusion independence was 105 days (range, 37 to 670). At the time of BM harvest, 10 patients were in second remission, one patient was in first remission, and one patient was in third remission. Eight patients relapsed 3 to 18 months after BMT. Four patients transplanted in second remission remain disease-free 34+, 37+, 52+, and 57+ months after BMT. There was no treatment-related mortality. Early engraftment was significantly delayed in patients receiving CD33-purged autografts compared with concurrently treated patients receiving CD9/CD10-purged autografts for acute lymphoblastic leukemia or patients receiving CD6-purged allografts from HLA- compatible sibling donors. In contrast, both groups of autograft patients required a significantly longer time to achieve neutrophil counts greater than 500/microL and greater than 1,000/microL than did patients receiving normal allogeneic marrow. CD33(+)-committed myeloid progenitor cells thus appear to play an important role in the early phase of hematopoietic reconstitution after BMT. However, our results also show that human marrow depleted of CD33+ cells can sustain durable engraftment after myeloablative therapy, and provide further evidence that the CD33 antigen is absent from the human pluripotent hematopoietic stem cell.

The Critical Role of Peptidyl-Prolyl cis/trans Isomerase, Pin1 in Acute Myeloid Leukemia with C/EBPalpha Mutations.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2213-2213
Author(s):  
J. Pulikkan ◽  
A. Peer Zada ◽  
M. Geletu ◽  
V. Dengler ◽  
Daniel G. Tenen ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Dominant Negative ◽  
Pcr Analysis ◽  
Wild Type ◽  
Rt Pcr ◽  
Promoter Assay ◽  
Type C ◽  
Acute Myeloid

Abstract CCAAT enhancer binding protein alpha (C/EBPα) is a myeloid specific transcription factor that coordinates cellular differentiation and cell cycle arrest. Loss of C/EBPα expression or function in leukemic blasts contributes to a block in myeloid cell differentiation. C/EBPα is mutated in around 9% of acute myeloid leukemia (AML). The mutations reported in C/EBPα are frame shift mutations and point mutations at basic region Leucine zipper. The mutant form of C/EBPα ie C/EBPα-p30 exhibits dominant negative function over the wild type protein. The role of peptidyl-prolyl cis/trans isomerase, Pin1 in tumorogenesis and its overexpression in many cancers led us to investigate its role in acute myeloid leukemia with C/EBPα mutation. Here we show that Pin1 is upregulated in patients with acute myeloid leukemia by affymetrix analysis. By quantitative Real-Time RT-PCR analysis, we show C/EBPα-p30 could induce Pin1 transcription, while the wild type C/EBPα downregulates Pin1 expression. Luciferase promoter assay for the Pin1 promoter shows that wild type C/EBPα is able to block Pin1 promoter activity. Mean while, C/EBPα-p30 couldn’t block Pin1 promotor activity. By silencing Pin1 by RNA Interference as well as with inhibitor against Pin1 (PiB) we could show myeloid differentiation in human CD34+ cord blood cells as well as in Kasumi-6 cells as assessed by FACS analysis with granulocytic markers. We investigated the mechanism underlying the dominant negative action of C/EBPα-p30 over the wild type protein. We report that Pin1 increases the transcriptional activity of the oncogene c-jun. We also show that c-jun blocks the DNA binding and transactivation of C/EBPα protein as assessed by gel shift assay and promoter assay respectively. We have previously shown that c-jun expression is high in AML patients with C/EBPα mutation and c-jun could block C/EBPα function by protein-protein interaction. Quantitative Real-Time RT-PCR analysis shows that inhibition of Pin1 by the inhibitor PiB downregulates c-jun mRNA expression. In conclusion, inhibition of Pin1 leads to granulocytic differentiation. Our results show Pin1 as a novel target in treating AML patients with C/EBPα mutation.

MicroRNA-29a Is An Oncogene in Acute Myeloid Leukemia

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 683-683
Author(s):  
Christopher Y. Park ◽  
Yoon-Chi Han ◽  
Govind Bhagat ◽  
Jian-Bing Fan ◽  
Irving L Weissman ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Stem Cells ◽  
Acute Myeloid Leukemia ◽  
Hematopoietic Stem Cells ◽  
Mirna Expression ◽  
Myeloid Leukemia ◽  
Hematopoietic Stem ◽  
Acute Myeloid

Abstract microRNAs (miRNAs) are short, non-protein encoding RNAs that bind to the 3′UTR’s of target mRNAs and negatively regulate gene expression by facilitating mRNA degradation or translational inhibition. Aberrant miRNA expression is well-documented in both solid and hematopoietic malignancies, and a number of recent miRNA profiling studies have identified miRNAs associated with specific human acute myeloid leukemia (AML) cytogenetic groups as well as miRNAs that may prognosticate clinical outcomes in AML patients. Unfortunately, these studies do not directly address the functional role of miRNAs in AML. In fact, there is no direct functional evidence that miRNAs are required for AML development or maintenance. Herein, we report on our recent efforts to elucidate the role of miRNAs in AML stem cells. miRNA expression profiling of AML stem cells and their normal counterparts, hematopoietic stem cells (HSC) and committed progenitors, reveals that miR-29a is highly expressed in human hematopoietic stem cells (HSC) and human AML relative to normal committed progenitors. Ectopic expression of miR-29a in mouse HSC/progenitors is sufficient to induce a myeloproliferative disorder (MPD) that progresses to AML. During the MPD phase of the disease, miR-29a alters the composition of committed myeloid progenitors, significantly expedites cell cycle progression, and promotes proliferation of hematopoietic progenitors at the level of the multipotent progenitor (MPP). These changes are manifested pathologically by marked granulocytic and megakaryocytic hyperplasia with hepatosplenomegaly. Mice with miR-29a-induced MPD uniformly progress to an AML that contains a leukemia stem cell (LSC) population that can serially transplant disease with as few as 20 purified LSC. Gene expression analysis reveals multiple tumor suppressors and cell cycle regulators downregulated in miR-29a expressing cells compared to wild type. We have demonstrated that one of these genes, Hbp1, is a bona fide miR-29a target, but knockdown of Hbp1 in vivo does not recapitulate the miR-29a phenotype. These data indicate that additional genes are required for miR-29a’s leukemogenic activity. In summary, our data demonstrate that miR-29a regulates early events in normal hematopoiesis and promotes myeloid differentiation and expansion. Moreover, they establish that misexpression of a single miRNA is sufficient to drive leukemogenesis, suggesting that therapeutic targeting of miRNAs may be an effective means of treating myeloid leukemias.

The Influence of Monosomal Karyotype On Survival in Patients with Acute Myeloid Leukemia After Allogeneic Hematopoietic Stem Cell Transplantation: A Retrospective Survey On Behalf of the Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT)

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 158-158 ◽  
Author(s):  
Angelique V.M. Brands-Nijenhuis ◽  
Myriam Labopin ◽  
Harry C. Schouten ◽  
Liisa Volin ◽  
Gérard Socié ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Stem Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Stem Cell Transplantation ◽  
Myeloid Leukemia ◽  
Poor Prognosis ◽  
Complex Karyotype ◽  
Hematopoietic Stem ◽  
Monosomal Karyotype ◽  
Acute Myeloid

Abstract Abstract 158 Introduction: Monosomal karyotype (MK) has been shown to be associated with a very poor prognosis in AML patients (Breems, 2008). Whether allogeneic hematopoietic stem cell transplantation (alloHSCT) performed in an early phase can overcome the adverse prognosis in this cytogenetic patient category is currently unknown. To address this issue we performed a retrospective analysis on data from the registry of the EBMT among patients with primary AML who underwent alloHSCT in CR1. Patients and methods: A total of 4119 patients with primary AML and known cytogenetic abnormalities at diagnosis that underwent alloHSCT in CR1 were included in the analysis. Survival curves were calculated with Kaplan-Meier method. Log rank test and Cox regression analysis were used to determine statistical significance. Results: Median follow-up was 24 months (range 2–374). Overall, 171 patients (4.2%) fulfilled criteria for MK and 297 patients (7.2%) for complex karyotype (CK), with 115 patients fulfilling both conditions (MK and CK). Both the presence of a MK (2-yr OS: 35.5% versus 63.2%, p<0.0001) and CK (2-yr OS: 48.8% versus 61.9%, p<0.0001) were associated with a poorer outcome when compared with the remaining cytogenetics subtypes. Given the significant overlap between both categories, we further analyzed their prognostic impact after defining four subgroups of patients: MK but not CK (56 patients; MK+CK-), no MK but CK (180 patients; MK-CK+), MK and CK (115 patients; MK+CK+), and patients without either MK or CK (MK-CK-). Outcome of the MK-CK- subgroup did not differ according to cytogenetics. Patients harboring a MK, regardless concomitant presence of a CK, presented with a poorer OS after alloHSCT (2-yr OS: 31.7–43.0% versus 61.1%, p<0.0001). On the contrary patients with a CK but not MK showed a similar outcome than MK-CK- (2-yr OS: 61.1% versus 63.3%, p=0.170). Moreover, multivariate analysis confirmed the independent negative impact of MK (HR:1.90, range 1.5–2.4; p<0.0001) together with age, interval diagnosis-transplant, AML subtype, WBC at diagnosis, T-cell depletion, number of induction cycles and use of TBI during conditioning, whereas the presence of a CK did not retain its negative prognostic value. Conclusion: These results indicate that MK is a better indicator for poor outcome than CK after alloHSCT in patients with primary AML in CR1. Nonetheless, the potential curative role of alloHSCT for a subset of patients with MK should be further investigated. Reference: DA Breems, WLJ van Putten, GE de Greef, SL van Zelderen-Bhola, KBJ Gerssen-Schoorl, CHM Mellink, A Nieuwint et al. Monosomal karyotype in acute myeloid leukemia: a better indicator of poor prognosis than a complex karyotype. J Clin Oncol 2008;26(29):4791–7. Disclosures: No relevant conflicts of interest to declare.

Sign in / Sign up

Export Citation Format

Share Document