In Vitro Efficacy of a Novel Liposomal Formulation of a Protein Kinase C Inhibitor In the Treatment of Acute Myeloid Leukemia

Abstract Abstract 3282 The prognosis of patients with acute myeloid leukemia (AML) remains poor, despite the use of the first-line, anthracycline- and cytarabine-based induction chemotherapy aiming to induce complete remission in patients. Given the recent findings that intensive chemotherapy may not benefit older leukemia patients who are not candidates for stem cell transplantation (Kantarjian, H. et al, Blood, 2010; DOI: 10.1182/blood-2010-03-276485) and that the monoclonal antibody-based cytotoxic agent, gemtuzumab ozogamicin, has been voluntarily withdrawn from the market, there is a pressing need to find effective treatment for recurrent AML patients who are >60 years. Safingol [(2S, 3S)-2-amino-1,3-octadecanediol] is a potential anti-cancer bioactive lipid that induces apoptosis through PKC inhibition in leukemia cells and other cancer types. Owing to its poor solubility, safingol is administered as an oil-based emulsion; however, this formulation suffers from severe hemolysis as the dose-limiting toxicity in pre-clinical models, and its toxicity profile is yet to be determined from an ongoing Phase I clinical trial for advanced solid tumors. Liposome is a commonly used drug delivery system to solubilize hydrophobic drugs. It is anticipated that liposome encapsulation of safingol would yield a viable injectable drug product without the need of toxic vehicle such as ethanol or Cremophor-EL, and would substantially reduce the hemolytic toxicity of safingol. In this study, our intention is to develop a suitable liposome formulation of safingol and to test its therapeutic efficacy using human AML cell lines and primary patient samples. Safingol could be formulated into stable liposomes using distearyolphosphatidylcholine and cholesterol with encapsulation efficiency of ∼100%. Safingol was released from the liposomes with a sustained release profile, mainly by a diffusion-controlled mechanism. The extent of hemolysis of 0.5 mM safingol could be significantly reduced from 76% to 14% through liposome encapsulation, as determined by an in vitro hemolysis assay. The cytotoxicity of liposomal safingol was tested with MTT assay on various AML cell lines representing different subtypes, including KG-1 (M1), HL-60 (M2), NB4 (M3), U937 (M5), MV4-11 (M5) and HEL (M6), as well as K562, a cell line of blast crisis of chronic myelogenous leukemia (BC-CML). All cell lines tested responded well to the treatment of liposomal safingol, with IC50 values ranging from 1.5–14 μM. Among the various AML subtypes, NB4 was found to be the most sensitive cell line with the lowest IC50 value of 1.5±0.2 μM. Importantly, liposome encapsulation of safingol did not compromise the ability of the drug to induce apoptosis as compared to the free drug, which was mediated possibly through a mechanism dependent on the generation of reactive oxygen species and caspase activation. Liposomal safingol was further tested in 10 leukemic patient samples, and the formulation was able to induce complete loss of viability of the primary cell samples at 20 μM after 72 h of treatment. Taken together, our results demonstrated the therapeutic potential of liposomal safingol for the treatment of various AML subtypes. Further evaluation of the pharmacokinetics and the efficacy of the formulation in animal models is warranted. Disclosures: No relevant conflicts of interest to declare.

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Deregulated Apoptotic Pathways Point to Effectiveness of IAP Inhibitor Therapy in Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v114.22.1275.1275 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1275-1275

Author(s):

Sonja C Lück ◽

Annika C Russ ◽

Konstanze Döhner ◽

Ursula Botzenhardt ◽

Domagoj Vucic ◽

...

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Cell Line ◽

Cell Lines ◽

Myeloid Leukemia ◽

Gene Set Enrichment Analysis ◽

Core Binding Factor ◽

Binding Factor ◽

Acute Myeloid

Abstract Abstract 1275 Poster Board I-297 Core binding factor (CBF) leukemias, characterized by translocations t(8;21) or inv(16)/t(16;16) targeting the core binding factor, constitute acute myeloid leukemia (AML) subgroups with favorable prognosis. However, 40-50% of patients relapse, and the current classification system does not fully reflect the heterogeneity existing within the cytogenetic subgroups. Therefore, illuminating the biological mechanisms underlying these differences is important for an optimization of therapy. Previously, gene expression profiling (GEP) revealed two distinct CBF leukemia subgroups displaying significant outcome differences (Bullinger et al., Blood 2007). In order to further characterize these GEP defined CBF subgroups, we again used gene expression profiles to identify cell line models similar to the respective CBF cohorts. Treatment of these cell lines with cytarabine (araC) revealed a differential response to the drug as expected based on the expression patterns reflecting the CBF subgroups. In accordance, the cell lines resembling the inferior outcome CBF cohort (ME-1, MONO-MAC-1, OCI-AML2) were less sensitive to araC than those modeling the good prognostic subgroup (Kasumi-1, HEL, MV4-11). A previous gene set enrichment analysis had identified the pathways Caspase cascade in apoptosis and Role of mitochondria in apoptotic signaling among the most significant differentially regulated BioCarta pathways distinguishing the two CBF leukemia subgroups. Thus, we concluded that those pathways might be interesting targets for specific intervention, as deregulated apoptosis underlying the distinct subgroups should also result in a subgroup specific sensitivity to apoptotic stimuli. Therefore, we treated our model cell lines with the Smac mimetic BV6, which antagonizes inhibitor of apoptosis (IAP) proteins that are differentially expressed among our CBF cohorts. In general, sensitivity to BV6 treatment was higher in the cell lines corresponding to the subgroup with good outcome. Time-course experiments with the CBF leukemia cell line Kasumi-1 suggested a role for caspases in this response. Interestingly, combination treatment of araC and BV6 in Kasumi-1 showed a synergistic effect of these drugs, with the underlying mechanisms being currently further investigated. Based on the promising sensitivity to BV6 treatment in some cell lines, we next treated mononuclear cells (mostly leukemic blasts) derived from newly diagnosed AML patients with BV6 in vitro to evaluate BV6 potency in primary leukemia samples. Interestingly, in vitro BV6 treatment also discriminated AML cases into two distinct populations. Most patient samples were sensitive to BV6 monotherapy, but about one-third of cases were resistant even at higher BV6 dosage. GEP of BV6 sensitive patients (at 24h following either BV6 or DMSO treatment) provided insights into BV6-induced pathway alterations in the primary AML patient samples, which included apoptosis-related pathways. In contrast to the BV6 sensitive patients, GEP analyses of BV6 resistant cases revealed no differential regulation of apoptosis-related pathways in this cohort. These results provide evidence that targeting deregulated apoptosis pathways by Smac mimetics might represent a promising new therapeutic approach in AML and that GEP might be used to predict response to therapy, thereby enabling novel individual risk-adapted therapeutic approaches. Disclosures Vucic: Genentech, Inc.: Employment. Deshayes:Genentech, Inc.: Employment.

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The BTK Inhibitor Ibrutinib Blocks SDF1/CXCR4 Mediated Migration of Acute Myeloid Leukemia Cells

Blood ◽

10.1182/blood.v124.21.915.915 ◽

2014 ◽

Vol 124 (21) ◽

pp. 915-915

Author(s):

Stuart A Rushworth ◽

Lyubov Zaitseva ◽

Megan Y Murray ◽

Matthew J Lawes ◽

David J MacEwan ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Cell Lines ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Lymphocytic Leukemia ◽

Cell Trafficking ◽

Acute Myeloid

Abstract Introduction Despite recent significant progress in the understanding of the biology of acute myeloid leukemia (AML) the clinical outcomes for the majority of patients diagnosed with AML presently remain poor. Consequently, there is an urgent need to identify pharmacological strategies in AML, which are not only effective but can be tolerated by the older, less well patient. Recently our group and others have shown that there is high Bruton’s Tyrosine Kinase (BTK) phosphorylation and RNA expression in AML. Moreover, our recent study described for the first time that ibrutinib and BTK-targeted RNA interference reduced factor-induced proliferation of both AML cell lines and primary AML blasts, as well as reducing AML blast adhesion to bone marrow stromal cells. Inhibition of BTK has been shown to regulate chronic lymphocytic leukemia, mantle cell lymphoma and multiple myeloma cell migration by inhibiting SDF1 (stromal derived factor 1) induced CXCR4 regulated cell trafficking. Here we report that in human AML ibrutinib in addition functions in a similar way to inhibit SDF1/CXCR4-mediated AML migration at concentrations achievable in vivo. Methods To investigate the role of BTK in regulating AML migration we used both pharmacological inhibitor ibrutinib and genetic knockdown using a lentivirus mediated BTK targeted miRNA in primary AML blasts and AML cell lines. We examined migration of AML blasts and AML cells to SDF-1 using Transwell permeable plates with 8.0µM pores. Western blotting was used to examine the role of SDF-1 in regulating BTK, AKT and MAPK activation in primary AML blasts. Results We initially examined the expression of CXCR4 in human AML cell lines and found that 4/4 cell lines were positive for CXCR4 expression. Next we examined the effects of ibrutinib on the migration of the AML cell lines U937, MV4-11, HL60 and THP-1 in response to SDF1. We found that ibrutinib can inhibit the migration of all AML cell lines tested. We tested the in-vitro activity of ibrutinib on SDF-1 induced migration in a spectrum of primary AML blasts from a wide age spectrum of adult patients and across a range of WHO AML subclasses and found that ibrutinib significantly inhibits primary AML blast migration (n=12). Next we found that ibrutinib can inhibit SDF-1 induced BTK phosphorylation and downstream MAPK and AKT signalling in primary AML blast. Finally to eliminate the problems associated with off target ibrutinib activity we evaluated migration of AML cells lines using genetic inhibition of BTK. The introduction of BTK-specific miRNA dramatically inhibited the expression of BTK in THP-1 and HL60 and reduced SDF1 mediated migration confirming that BTK is involved in regulating AML migration in response to SDF1. Conclusions These results reported here provide a molecular mechanistic rationale for clinically evaluating BTK inhibition in AML patients and suggests that in some AML patients the blasts count may initially rise in response to ibrutinib therapy, analgous to similar clinical observations in CLL. Disclosures No relevant conflicts of interest to declare.

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Vgamma9Vdelta2 T Cells-Based Immunotherapy Targeting BTN3 Molecules in Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v124.21.3726.3726 ◽

2014 ◽

Vol 124 (21) ◽

pp. 3726-3726

Author(s):

Daniel Olive ◽

Audrey Benyamine ◽

Aude Le Roy ◽

Rémy Castellano ◽

Julie Gertner-Dardenne ◽

...

Keyword(s):

T Cells ◽

Acute Myeloid Leukemia ◽

Cell Lines ◽

Myeloid Leukemia ◽

Mevalonate Pathway ◽

Conflicts Of Interest ◽

Tumor Burden ◽

Acute Myeloid

Abstract As they can kill Acute Myeloid Leukemia (AML) blasts in vitro and in vivo, Vg9Vd2T cells are key players in the design of new strategies of immunotherapy. AminoBisphonates (NBP) can enhance their activation in vitro and in vivo. Their combination with low-dose IL2 has shown promising results in 2 patients with AML who underwent partial remission. NBP treatment of blasts inhibits the Mevalonate pathway. The subsequent accumulation of Isopentenyl Diphosphate sensitize AML blasts to Vg9Vd2T cells killing but some AML cell lines blasts are resistant to this TCR mediated-lysis. Butyrophilin 3 A1 (BTN3A1) has been shown to be involved in IPP recognition and Vg9Vd2 T cells activation. Agonist monoclonal antibodies (mAb) recognizing the 3 isoforms of BTN3, can trigger BTN3 on tumor cell lines and sensitize them to Vg9Vd2 T cells lysis. We show that primary AML blasts from patient at diagnosis are heterogeneously killed by allogenic-IL-2-NBP-expanded Vg9Vd2 T. Some are resistant to this lysis and/or poorly sensitized by NBP. BTN3 molecules are highly expressed by blasts of AML cell lines and primary AML samples. We show that treatment of primary AML blasts with agonist anti-BTN3 mAb can overcome the resistance to Vg9Vd2 cells lysis in vitro. We assess this effect in vivo, showing that the addition of agonist anti-BTN3 mAb to Vg9Vd2 cells infusion decreased the tumor burden and increased the survival of NOG mice xenografted with luciferase-transduced U937 cell line. We confirm this effect in a model of mice xenografted with primary AML blasts, showing that treatment with anti-BTN3 mAb added to Vg9Vd2 cells infusion can decrease the number of blastic cells in the spleen, bone marrow and the blood, without requiring additional cytokine infusion. This drastic effect on sensitization of primary AML blasts to Vg9Vd2T cells killing could be of great interest especially in cases of refractory or relapsing AML. Disclosures No relevant conflicts of interest to declare.

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FLT3 Expression Is Increased by MEIS1 and Collaborates with NUP98-HOX Fusion Genes in the Induction of Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v104.11.2552.2552 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2552-2552

Author(s):

Lars Palmqvist ◽

Nicolas Pineault ◽

Bob Argiropoulos ◽

Adrian Wan ◽

Keith R. Humphries

Keyword(s):

Acute Myeloid Leukemia ◽

Cell Line ◽

Cell Lines ◽

Myeloid Leukemia ◽

Parental Cell ◽

Fusion Genes ◽

Flt3 Ligand ◽

Flt3 Expression ◽

Acute Myeloid

Abstract The TALE family member and HOX cofactor MEIS1 is important in leukemic transformation. MEIS1 has, although non-leukemogenic on its own, been shown to strongly collaborate with several HOX genes and NUP98-HOX fusions to induce acute myeloid leukemia (AML). We have recently described a novel in vitro culture system of cell lines established from murine primary bone marrow cells transduced with the AML-associated fusion gene NUP98-HOXD13 or an engineered NUP98-HOXA10 fusion. These pre-leukemic NUP98-HOX cell lines are transplantable and can efficiently be converted into AML-inducing cells upon MEIS1 transduction. Conveniently, the MEIS1 transduced cells can be purified and preserve their leukemogenic potential even after extensive in vitro expansion. Thus, the availability of the NUP98-HOX cell lines system provided the opportunity to investigate and characterize the mechanism of MEIS1-mediated AML-conversion. Potentially interesting target or candidate genes were screened for expression changes between the parental pre-leukemic lines and AML-inducing MEIS1 transduced cell lines with quantitative RT-PCR and Western blotting. Aberrant expression or mutations of the receptor tyrosine kinase FLT3 gene is a common finding in human AML. Interestingly, Flt3 was found induced 5 to 10 fold in MEIS1 transduced cell lines compared to the parental cell lines. The observed increase in Flt3 expression provided the MEIS1 transduced cells with Flt3 ligand driven growth. This was not seen in the parental cell lines, which could not proliferate with Flt3 ligand as single cytokine or with a MEIS1-homeodomain mutant expressing cell line. Importantly, the Flt3 inhibitor AG1295 could block the proliferative effect of the Flt3 ligand in the MEIS1 transduced cell lines. To test whether Flt3 could substitute for MEIS1-mediated induction of AML in NUP98-HOX pre-leukemic cells, a NUP98-HOXA10 cell line was transduced with an MSCV-Flt3-IRES-YFP construct. The resulting Flt3-transduced cells were shown to express Flt3 at levels similar to that of MEIS1 transduced cells without any significant increase in endogenous Meis1 expression. Transplantation of these cells into mice led to lethal and transplantable AML with a median disease onset of 116 days (n=8) compared to 59 days for MEIS1 (n=4), whereas control transplants remained healthy (n=2). In conclusion, this study demonstrates that MEIS1 can induce Flt3 expression and that Flt3 can collaborate with NUP98-HOX fusion genes in the induction of acute myeloid leukemia. Furthermore, theses results suggest a model in which the leukemogenic synergism of MEIS1 on HOX-mediated leukemia might in part be mediated through FLT3-dependent pathways.

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The PARP Inhibitor Olaparib Antagonizes Leukemic Growth Induced By TET1 Overexpression in AML1-ETO Positive Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v128.22.4063.4063 ◽

2016 ◽

Vol 128 (22) ◽

pp. 4063-4063 ◽

Cited By ~ 1

Author(s):

Shiva Bamezai ◽

Jing He ◽

Deniz Sahin ◽

Fabian Mohr ◽

Fabio Ciccarone ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Cell Growth ◽

Cell Line ◽

Cell Lines ◽

Myeloid Leukemia ◽

Parp Inhibitor ◽

Leukemic Cell ◽

Aberrant Expression ◽

Acute Myeloid

Abstract DNA methylation patterns are highly deregulated in human acute myeloid leukemia (AML) cases and stratify AML patient samples into different subgroup. AML1-ETO is the most commonly occurring fusion gene in AML and these AML cases exhibit an aberrant and distinct methylation pattern. So far, the underlying mechanisms for this are only poorly understood. The TET1 dioxygenase has recently emerged as an important epigenetic modifier: by catalyzing the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) TET1 plays an important role in active demethylation, thereby regulating a variety of biological processes. It was linked to tumorigenesis based on the observation that its expression is frequently deregulated in solid cancer. However, the role of TET1 in AML1-ETO+ (AE+)human AML cases is yet unexplored. Using quantitative real time (qRT)- PCR we now show that AE+ AML is characterized by high and aberrant expression of TET1: the gene was significantly higher expressed in the majority of AE+ patients (n=7, p<0.01) compared to other AML subtypes such as inv(16) (n=11), PML-RARα+ (n=31), cytogenetically normal (CN)-AML patients (n=33) and CD34+ normal BM cells (n=4). This observation was consistent with published cDNA microarray data on large patient cohorts (Haferlach et al., JCO 2010, p<0.008 t-test, p<0.01 Anova) and recently published transcriptome data (TCGA) of AML patients. In contrast to TET1, TET2 and TET3 did not show significant higher expression in AE+ patients compared to other AML subtypes. In line with patient data, TET1 was highest expressed in the AE+ AML cell line KASUMI-1 and SKNO-1 compared to other AML cell lines (p<0.05 and n=3). Compared to normal CD34+ and myeloid (CD33+, CD15+ and CD14+) cells (n=3), TET1 was 10-fold and 16-fold higher expressed in AE+ patient samples (n= 7). Aberrant expression of TET1 in AE+ leukemic cells was associated with hypomethylation of its promoter and enrichment for H3K4me3 euchromatic marks at its promoter as determined by LC/MS and ChIP-qPCR respectively. Knockdown (KD) of TET1 mRNA using two short hairpin RNAs (shRNAs) in AE+ AML cell lines impaired their cell growth and clonogenicity by over 50% in vitro (n=3 and p<0.01). shRNA mediated depletion of TET1 did not impact the cell growth and clonogenicity of the TET1 negative cell line RAJI, ruling out off target effects of the shRNAs (n=3). In mice, KD of Tet1 in leukemic bone marrow cells expressing the truncated leukemogenic AML1-ETO9a (AE9a) fusion, dramatically inhibited cell growth (>60% compared to scrambled, n=3, p<0.01), clonogenicity (>50-70% reduction in primary CFCs, p<0.01, n=3) and importantly delayed onset of leukemia in vivo (median survival 35 days for scr vs 80 days for shRNA mice, n=4/arm, p<0.03). Tet1-knock-out c-kit+ hematopoietic stem and progenitor cells (HSPCs) transduced with AE9a showed reduced primary colony formation and impaired serial replanting capacity in vitro compared to AE9a transduced Tet1-wild-type HSPCs (>50% and >70%, respectively; p<0.001, n=3). Global analysis of 5hmC and 5mC levels using hMeDIP/MeDIP-seq performed on TET1 depleted KASUMI-1 cells revealed lower global 5hmC levels and increase in 5mC as compared to cells transduced with scrambled control (n=2). 3324 promoter regions lost 5hmC and gained 5mC upon TET1 depletion (-5kTSS, Fold enrichment cut off <2-fold, q-value<1e5). Recent studies have shown that PARP activity induces TET1 expression by regulating its promoter epigenetically. We could show that aberrant TET1 expression could be antagonized by the PARP inhibitor olaparib in AE+ leukemic cell lines. Furthermore, olaparib treatment decreased 5hmC levels and reduced cell growth and clonogenicity of human AE+ cell lines and of the murine AE9a+ leukemic cell line in vitro (n=3, p<0.01). In conclusion, our data indicates that aberrant TET1 expression contributes to the growth of AE+ AML by maintaining the 5-hydroxymethylome and that the PARP inhibitor olaparib can at least partially antagonize the oncogenic effect of TET in AML. Disclosures Mulaw: NuGEN: Honoraria. Buske:Celltrion, Inc.: Consultancy, Honoraria.

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Phosphotyrosine profiling identifies the KG-1 cell line as a model for the study of FGFR1 fusions in acute myeloid leukemia

Blood ◽

10.1182/blood-2006-06-026666 ◽

2006 ◽

Vol 108 (13) ◽

pp. 4202-4204 ◽

Cited By ~ 51

Author(s):

Ting-Lei Gu ◽

Valerie L. Goss ◽

Cynthia Reeves ◽

Lana Popova ◽

Julie Nardone ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Cell Line ◽

Cell Lines ◽

Myeloid Leukemia ◽

Leukemia Cell ◽

Mass Spectrometry Analysis ◽

Leukemia Cell Lines ◽

Fgfr1 Gene ◽

Acute Myeloid

Abstract The 8p11 myeloproliferative syndrome (EMS) is associated with translocations that disrupt the FGFR1 gene. To date, 8 fusion partners of FGFR1 have been identified. However, no primary leukemia cell lines were identified that contain any of these fusions. Here, we screened more than 40 acute myeloid leukemia cell lines for constitutive phosphorylation of STAT5 and applied an immunoaffinity profiling strategy to identify tyrosine-phosphorylated proteins in the KG-1 cell line. Mass spectrometry analysis of KG-1 cells revealed aberrant tyrosine phosphorylation of FGFR1. Subsequent analysis led to the identification of a fusion of the FGFR1OP2 gene to the FGFR1 gene. Small interfering RNA (siRNA) against FGFR1 specifically inhibited the growth and induced apoptosis of KG-1 cells. Thus, the KG-1 cell line provides an in vitro model for the study of FGFR1 fusions associated with leukemia and for the analysis of small molecule inhibitors against FGFR1 fusions.

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Extracellular ATP and CD39 Regulates Mitochondrial Function and Cytarabine Resistance through Intrinsic PKA-ATF-PGC1a Pathway in Acute Myeloid Leukemia

Blood ◽

10.1182/blood-2018-99-112534 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 2737-2737

Author(s):

Jean-Emmanuel Sarry ◽

Christian Recher ◽

Nesrine Aroua

Keyword(s):

Acute Myeloid Leukemia ◽

Cell Lines ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Leukemic Cells ◽

Nucleoside Triphosphate ◽

Preclinical Model ◽

Acute Myeloid

Abstract Relapses in acute myeloid leukemia (AML) are caused by chemoresistant leukemic populations and new therapeutic approaches that specifically target these cells are urgently needed. Based on transcriptomic analyses of relevant PDX preclinical model of the resistance to cytarabine (AraC) and of the residual disease in patients, we identified ecto-nucleoside triphosphate diphosphohydrolase-1 CD39 (ENTPD1) overexpressed in the residual leukemic cells in vivo after chemotherapy. By flow cytometry, we confirmed that AraC increased cell surface CD39 expression in AML cell lines in vitro and in vivo as well as in 24 diverse patient-derived xenograft models. We further observed this increase in 100 patients at 35-days post-intensive chemotherapy compared to their respective diagnosis. Interestingly, high CD39 expression on AML patients was associated with a worse response to AraC in vivo. Furthermore, we showed that FACS-sorted CD39high AML cells had increased mitochondrial mass and activity, and were resistant to AraC in vitro and in vivo. We demonstrated that CD39 downstream signaling pathway was dependent on cAMP-PKA-PGC1a-TFAM axis and its inhibition by H89 sensitized AML cells to AraC through the inhibition of mitochondrial OxPHOS biogenesis and function. Finally, pharmacological inhibition of CD39 ATP hydrolase activity or genetic invalidation of CD39 protein using two inhibitors or shRNA markedly enhanced AraC cytotoxicity in AML cell lines and primary patient samples in vitro and in vivo. Together, these results indicate CD39 as a new player of the intrinsic chemoresistance pathway and a new therapeutic target to specifically overcome AraC resistance and eradicate these leukemic cells responsible for relapses in AML. Disclosures No relevant conflicts of interest to declare.

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Anti-leukemia properties of cadmium nanoparticles in the in vitro and in vivo condition: A chemobiological study

Archives of Medical Science ◽

10.5114/aoms/142465 ◽

2021 ◽

Author(s):

Yudi Miao ◽

Behnam Mahdavi ◽

Mohammad Zangeneh

Keyword(s):

Acute Myeloid Leukemia ◽

Cell Lines ◽

Aqueous Extract ◽

Myeloid Leukemia ◽

Antioxidant Properties ◽

Leukemia Cell ◽

Sem Images ◽

Acute Myeloid

IntroductionThe present study investigated the anti-acute myeloid leukemia effects of Ziziphora clinopodides Lam leaf aqueous extract conjugated cadmium nanoparticles.Material and methodsTo synthesize CdNPs, Z. clinopodides aqueous extract was mixed with Cd(NO3)2 .4H2O. The characterization of the biosynthesized cadmium nanoparticles was carried out using many various techniques such as UV-Vis. and FT-IR spectroscopy, XRD, FE-SEM, and EDS.ResultsThe uniform spherical morphology of NPs was proved by FE-SEM images with NPs the average size of 26.78cnm. For investigating the antioxidant properties of Cd(NO3)2, Z. clinopodides, CdNPs, and Daunorubicin, the DPPH test was used. The cadmium nanoparticles inhibited half of the DPPH molecules in a concentration of 196 µg/mL. To survey the cytotoxicity and anti-acute myeloid leukemia effects of Cd(NO3)2, Z. clinopodides, CdNPs, and Daunorubicin, MTT assay was used on the human acute myeloid leukemia cell lines i.e., Murine C1498, 32D-FLT3-ITD, and Human HL-60/vcr. The IC50 of the cadmium nanoparticles was 168, 205, and 210 µg/mL against Murine C1498, 32D-FLT3-ITD, and Human HL-60/vcr cell lines, respectively. In the part of in vivo study, DMBA was used for inducing acute myeloid leukemia in mice. CdNPs similar to daunorubicin ameliorated significantly (p≤0.01) the biochemical, inflammatory, RBC, WBC, platelet, stereological, histopathological, and cellular-molecular parameters compared to the other groups.ConclusionsAs mentioned, the cadmium nanoparticles had significant anti-acute myeloid leukemia effects. After approving the above results in the clinical trial studies, these cadmium nanoparticles can be used as a chemotherapeutic drug to treat acute myeloid leukemia in humans.

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The Salt-Inducible Kinase inhibitor YKL-05-099 suppresses MEF2C function and acute myeloid leukemia progressionin vivo

10.1101/636969 ◽

2019 ◽

Author(s):

Yusuke Tarumoto ◽

Shan Lin ◽

Jinhua Wang ◽

Joseph P. Milazzo ◽

Yali Xu ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Disease Progression ◽

Cell Lines ◽

Myeloid Leukemia ◽

Kinase Inhibitor ◽

Clinical Investigation ◽

Genetic Targeting ◽

Acute Myeloid

AbstractLineage-defining transcription factors (TFs) are compelling targets for leukemia therapy, yet they are among the most challenging proteins to modulate directly with small molecules. We previously used CRISPR screening to identify a Salt-Inducible Kinase 3 (SIK3) requirement for the growth of acute myeloid leukemia (AML) cell lines that overexpress the lineage TF MEF2C. In this context, SIK3 maintains MEF2C function by directly phosphorylating histone deacetylase 4 (HDAC4), a repressive cofactor of MEF2C. Here, we evaluated whether inhibition of SIK3 with the tool compound YKL-05-099 can suppress MEF2C function and attenuate disease progression in animal models of AML. Genetic targeting of SIK3 or MEF2C selectively suppressed the growth of transformed hematopoietic cells underin vitroandin vivoconditions. Similar phenotypes were obtained when exposing cells to YKL-05-099, which caused cell cycle arrest and apoptosis in MEF2C-expressing AML cell lines. An epigenomic analysis revealed that YKL-05-099 rapidly suppressed MEF2C function by altering the phosphorylation state and nuclear localization of HDAC4. Using a gatekeeper allele ofSIK3, we found that the anti-proliferative effects of YKL-05-099 occurred through on-target inhibition of SIK3 kinase activity. Based on these findings, we treated two different mouse models of MLL-AF9 AML with YKL-05-099, which attenuated disease progressionin vivoand extended animal survival at well-tolerated doses. These findings validate SIK3 as a therapeutic target in MEF2C-positive AML and provide a rationale for developing drug-like inhibitors of SIK3 for definitive pre-clinical investigation and for studies in human patients with leukemia.Key PointsAML cells are uniquely sensitive to genetic or chemical inhibition of Salt-Inducible Kinase 3in vitroandin vivo.A SIK inhibitor YKL-05-099 suppresses MEF2C function and AMLin vivo.

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The Vitamin E Derivative Gamma Tocotrienol Promotes Anti-Tumor Effects in Acute Myeloid Leukemia Cell Lines

Nutrients ◽

10.3390/nu11112808 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2808 ◽

Cited By ~ 6

Author(s):

Ghanem ◽

Zouein ◽

Mohamad ◽

Hodroj ◽

Haykal ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Vitamin E ◽

Cell Lines ◽

Myeloid Leukemia ◽

Apoptotic Cell ◽

Leukemia Cell ◽

Therapeutic Effects ◽

Apoptotic Pathway ◽

Acute Myeloid

Acute myeloid leukemia (AML) is a blood cancer characterized by the formation of faulty defective myelogenous cells with morphological heterogeneity and cytogenic aberrations leading to a loss of their function. In an attempt to find an effective and safe AML treatment, vitamin E derivatives, including tocopherols were considered as potential anti-tumor compounds. Recently, other isoforms of vitamin E, namely tocotrienols have been proposed as potential potent anti-cancerous agents, displaying promising therapeutic effects in different cancer types. In this study we evaluated the anti-cancerous effects of γ-tocotrienol, on AML cell lines in vitro. For this purpose, AML cell lines incubated with γ-tocotrienol were examined for their viability, cell cycle status, apoptotic cell death, DNA fragmentation, production of reactive oxygen species and expression of proapoptotic proteins. Our results showed that γ-tocotrienol exhibits time and dose-dependent anti-proliferative, pro-apoptotic and antioxidant effects on U937 and KG-1 cell lines, through the upregulation of proteins involved in the intrinsic apoptotic pathway.

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