Discovery of a Non-Nucleoside SETD2 Methyltransferase Inhibitor against Acute Myeloid Leukemia

Histone methyltransferases (HMTs) have attracted considerable attention as potential targets for pharmaceutical intervention in various malignant diseases. These enzymes are known for introducing methyl marks at specific locations of histone proteins, creating a complex system that regulates epigenetic control of gene expression and cell differentiation. Here, we describe the identification of first-generation cell-permeable non-nucleoside type inhibitors of SETD2, the only mammalian HMT that is able to tri-methylate the K36 residue of histone H3. By generating the epigenetic mark H3K36me3, SETD2 is involved in the progression of acute myeloid leukemia. We developed a structure-based virtual screening protocol that was first validated in retrospective studies. Next, prospective screening was performed on a large library of commercially available compounds. Experimental validation of 22 virtual hits led to the discovery of three compounds that showed dose-dependent inhibition of the enzymatic activity of SETD2. Compound C13 effectively blocked the proliferation of two acute myeloid leukemia (AML) cell lines with MLL rearrangements and led to decreased H3K36me3 levels, prioritizing this chemotype as a viable chemical starting point for drug discovery projects.

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RNA-dependent inhibition of ribonucleotide reductase is a major pathway for 5-azacytidine activity in acute myeloid leukemia

Blood ◽

10.1182/blood-2011-11-382226 ◽

2012 ◽

Vol 119 (22) ◽

pp. 5229-5238 ◽

Cited By ~ 80

Author(s):

Josephine Aimiuwu ◽

Hongyan Wang ◽

Ping Chen ◽

Zhiliang Xie ◽

Jiang Wang ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Ribonucleotide Reductase ◽

Myeloid Leukemia ◽

Mononuclear Cells ◽

Leukemia Cell ◽

Major Pathway ◽

Leukemia Cell Lines ◽

Dependent Inhibition ◽

First Time ◽

Acute Myeloid

Abstract 5-Azacytidine (5-azaC) is an azanucleoside approved for myelodysplastic syndrome. Approximately 80%-90% of 5-azaC is believed to be incorporated into RNA, which disrupts nucleic acid and protein metabolism leading to apoptosis. A smaller fraction (10%-20%) of 5-azaC inhibits DNA methylation and synthesis through conversion to decitabine triphosphate and subsequent DNA incorporation. However, its precise mechanism of action remains unclear. Ribonucleotide reductase (RR) is a highly regulated enzyme comprising 2 subunits, RRM1 and RRM2, that provides the deoxyribonucleotides required for DNA synthesis/repair. In the present study, we found for the first time that 5-azaC is a potent inhibitor of RRM2 in leukemia cell lines, in a mouse model, and in BM mononuclear cells from acute myeloid leukemia (AML) patients. 5-azaC–induced RRM2 gene expression inhibition involves its direct RNA incorporation and an attenuated RRM2 mRNA stability. Therefore, 5-azaC causes a major perturbation of deoxyribonucleotide pools. We also demonstrate herein that the initial RR-mediated 5-azaC conversion to decitabine is terminated through its own inhibition. In conclusion, we identify RRM2 as a novel molecular target of 5-azaC in AML. Our findings provide a basis for its more widespread clinical use either alone or in combination.

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Expression, Regulation and Function of microRNA as Important Players in the Transition of MDS to Secondary AML and Their Cross Talk to RNA-Binding Proteins

International Journal of Molecular Sciences ◽

10.3390/ijms21197140 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7140 ◽

Cited By ~ 1

Author(s):

Marcus Bauer ◽

Christoforos Vaxevanis ◽

Nadine Heimer ◽

Haifa Kathrin Al-Ali ◽

Nadja Jaekel ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Binding Proteins ◽

Rna Binding ◽

Rna Binding Proteins ◽

Significant Risk ◽

Control Of Gene Expression ◽

Hematopoietic Stem ◽

Molecular Abnormalities ◽

Acute Myeloid

Myelodysplastic syndromes (MDS), heterogeneous diseases of hematopoietic stem cells, exhibit a significant risk of progression to secondary acute myeloid leukemia (sAML) that are typically accompanied by MDS-related changes and therefore significantly differ to de novo acute myeloid leukemia (AML). Within these disorders, the spectrum of cytogenetic alterations and oncogenic mutations, the extent of a predisposing defective osteohematopoietic niche, and the irregularity of the tumor microenvironment is highly diverse. However, the exact underlying pathophysiological mechanisms resulting in hematopoietic failure in patients with MDS and sAML remain elusive. There is recent evidence that the post-transcriptional control of gene expression mediated by microRNAs (miRNAs), long noncoding RNAs, and/or RNA-binding proteins (RBPs) are key components in the pathogenic events of both diseases. In addition, an interplay between RBPs and miRNAs has been postulated in MDS and sAML. Although a plethora of miRNAs is aberrantly expressed in MDS and sAML, their expression pattern significantly depends on the cell type and on the molecular make-up of the sample, including chromosomal alterations and single nucleotide polymorphisms, which also reflects their role in disease progression and prediction. Decreased expression levels of miRNAs or RBPs preventing the maturation or inhibiting translation of genes involved in pathogenesis of both diseases were found. Therefore, this review will summarize the current knowledge regarding the heterogeneity of expression, function, and clinical relevance of miRNAs, its link to molecular abnormalities in MDS and sAML with specific focus on the interplay with RBPs, and the current treatment options. This information might improve the use of miRNAs and/or RBPs as prognostic markers and therapeutic targets for both malignancies.

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AC220 is a uniquely potent and selective inhibitor of FLT3 for the treatment of acute myeloid leukemia (AML)

Blood ◽

10.1182/blood-2009-05-222034 ◽

2009 ◽

Vol 114 (14) ◽

pp. 2984-2992 ◽

Cited By ~ 380

Author(s):

Patrick P. Zarrinkar ◽

Ruwanthi N. Gunawardane ◽

Merryl D. Cramer ◽

Michael F. Gardner ◽

Daniel Brigham ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

First Generation ◽

Drug Candidate ◽

Activating Mutations ◽

Cellular Assays ◽

Flt3 Inhibitor ◽

Pharmacokinetic Properties ◽

Acute Myeloid

Activating mutations in the receptor tyrosine kinase FLT3 are present in up to approximately 30% of acute myeloid leukemia (AML) patients, implicating FLT3 as a driver of the disease and therefore as a target for therapy. We report the characterization of AC220, a second-generation FLT3 inhibitor, and a comparison of AC220 with the first-generation FLT3 inhibitors CEP-701, MLN-518, PKC-412, sorafenib, and sunitinib. AC220 exhibits low nanomolar potency in biochemical and cellular assays and exceptional kinase selectivity, and in animal models is efficacious at doses as low as 1 mg/kg given orally once daily. The data reveal that the combination of excellent potency, selectivity, and pharmacokinetic properties is unique to AC220, which therefore is the first drug candidate with a profile that matches the characteristics desirable for a clinical FLT3 inhibitor.

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LRRC33 is a novel binding and regulating protein of TGF-β1 function in human acute myeloid leukemia cells

10.1101/560763 ◽

2019 ◽

Author(s):

Wenjiang Ma ◽

Yan Qin ◽

Bjoern Chapuy ◽

Chafen Lu

Keyword(s):

Acute Myeloid Leukemia ◽

Growth Factor ◽

Myeloid Leukemia ◽

Binding Proteins ◽

Transforming Growth Factor ◽

Mrna Level ◽

Leucine Rich Repeat ◽

Starting Point ◽

Tgf Β1 ◽

Acute Myeloid

AbstractTransforming growth factor – β1 (TGF-β1) is a versatile cytokine. It has context-dependent pro- and anti-cell proliferation functions. Activation of latent TGF-β1 requires release of the growth factor from pro-complexes and is regulated through TGF-β binding proteins. Two types of TGF-β binding partners, latent TGF-β-binding proteins (LTBPs) and leucine-rich-repeat-containing protein 32 (LRRC32), have been identified and their expression are cell specific. TGF-β1 also plays important roles in acute myeloid leukemia (AML) cells. However, the expression of LTBPs and LRRC32 are lacking in myeloid lineage cells and the binding protein of TGF-β1 in these cells are unknown. Here we show that a novel leucine-rich-repeat-containing protein family member, LRRC33, with high mRNA level in AML cells, to be the binding and regulating protein of TGF-β1 in AML cells. Using two representative cell lines MV4-11 and AML193, we demonstrate that the protein expression of LRRC33 and TGF-β1 are correlated. LRRC33 co-localizes and forms complex with latent TGF-β1 protein on the cell surface and intracellularly in these cells. Similar as in other cell types, the activation of TGF-β1 in MV4-11 and AML193 cells are also integrin dependent. We anticipate our study to be a starting point of more comprehensive research on LRRC33 as novel TGF-β regulating protein and potential non-genomic based drug target for AML and other myeloid malignancy.

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