su-11248 and Leukemia--Myeloid--Acute

Aberrant activation of FMS-like tyrosine receptor kinase 3 (FLT3) is implicated in the pathogenesis of acute myeloid leukemia (AML) in 20-30% of patients. In this study we identified a highly selective (phenylethenyl)quinazoline compound family as novel potent inhibitors of the FLT3-ITD and FLT3-D835Y kinases. Their prominent effects were confirmed by biochemical and cellular proliferation assays followed by mice xenograft studies. Our modelling experiments and the chemical structures of the compounds predict the possibility of covalent inhibition. The most effective compounds triggered apoptosis in FLT3-ITD AML cells but had either weak or no effect in FLT3-independent leukemic and non-leukemic cell lines. Our results strongly suggest that our compounds may become therapeutics in relapsing and refractory AML disease harboring various ITD and tyrosine kinase domain mutations, by their ability to overcome drug resistance.

Topics: Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Discovery; Drug Screening Assays, Antitumor; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Molecular Structure; Mutation; Protein Kinase Inhibitors; Pyrimidines; Structure-Activity Relationship

Gastrointestinal stromal tumors (GISTs) are prototypes of stem cell factor receptor (c-KIT)-driven cancer. Two receptor tyrosine kinases, c-KIT and fms-tyrosine kinase (FLT3), are frequently mutated in acute myeloid leukemia (AML) patients, and these mutations are associated with poor prognosis. In this study, we discovered a multitargeted tyrosine kinase inhibitor, compound

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Proliferation; Female; fms-Like Tyrosine Kinase 3; Gastrointestinal Neoplasms; Gastrointestinal Stromal Tumors; Humans; Leukemia, Myeloid, Acute; Male; Mice; Mice, Inbred ICR; Mice, Inbred NOD; Mice, Nude; Mice, SCID; Mutation; Phosphorylation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-kit; Pyrimidines; Rats, Sprague-Dawley; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Acute myeloid leukemia (AML) is the most common type of leukemia in adults. Sunitinib, a multikinase inhibitor, was the first Fms-like tyrosine kinase 3 (FLT3) inhibitor clinically used against AML. Off-target effects are a major concern for multikinase inhibitors. As targeted delivery may reduce such undesired side effects, our goal was to develop novel amino acid substituted derivatives of sunitinib which are potent candidates to be used conjugated with antibodies and peptides. In the current paper we present the synthesis, physicochemical and in vitro characterization of sixty two Fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutant kinase inhibitors, bearing amino acid moieties, fit to be conjugated with peptide-based delivery systems via their carboxyl group. We determined the solubility, pK

Topics: Amino Acids; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Molecular Structure; Protein Kinase Inhibitors; Solubility; Structure-Activity Relationship; Sunitinib; Tandem Repeat Sequences

Kinase inhibitors are important cancer therapeutics. Polypharmacology is commonly observed, requiring thorough target deconvolution to understand drug mechanism of action. Using chemical proteomics, we analyzed the target spectrum of 243 clinically evaluated kinase drugs. The data revealed previously unknown targets for established drugs, offered a perspective on the "druggable" kinome, highlighted (non)kinase off-targets, and suggested potential therapeutic applications. Integration of phosphoproteomic data refined drug-affected pathways, identified response markers, and strengthened rationale for combination treatments. We exemplify translational value by discovering SIK2 (salt-inducible kinase 2) inhibitors that modulate cytokine production in primary cells, by identifying drugs against the lung cancer survival marker MELK (maternal embryonic leucine zipper kinase), and by repurposing cabozantinib to treat FLT3-ITD-positive acute myeloid leukemia. This resource, available via the ProteomicsDB database, should facilitate basic, clinical, and drug discovery research and aid clinical decision-making.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cytokines; Drug Discovery; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Lung Neoplasms; Mice; Molecular Targeted Therapy; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Proteomics; Xenograft Model Antitumor Assays

A series of 6-acylureido derivatives containing a 3-(pyrrol-2-ylmethylidene)indolin-2-one scaffold were synthesized as potential dual Aurora B/FLT3 inhibitors by replacing the 6-arylureido moiety in 6-arylureidoindolin-2-one-based multi-kinase inhibitors. (Z)-N-(2-(pyrrolidin-1-yl)ethyl)-5-((6-(3-(2-fluoro-4-methoxybenzoyl)ureido)-2-oxoindolin-3-ylidene)methyl)-2,4-dimethyl-1H-pyrrole-3-carboxamide (54) was identified as a dual Aurora B/FLT3 inhibitor (IC50 = 0.4 nM and 0.5 nM, respectively). Compound 54 also exhibited potent cytotoxicity with single-digit nanomolar IC50 values against the FLT3 mutant-associated human acute myeloid leukemia (AML) cell lines MV4-11 (FLT3-ITD) and MOLM-13 (FLT3-ITD). Compound 54 also specifically induced extrinsic apoptosis by inhibiting the phosphorylation of the Aurora B and FLT3 pathways in MOLM-13 cells. Compound 54 had a moderate pharmacokinetic profile. The mesylate salt of 54 efficiently inhibited tumor growth and reduced the mortality of BALB/c nude mice (subcutaneous xenograft model) that had been implanted with AML MOLM-13 cells. Compound 54 is more potent than sunitinib not only against FLT3-WT AML cells but also active against sunitinib-resistant FLT3-ITD AML cells. This study demonstrates the significance of dual Aurora B/FLT3 inhibitors for the development of potential agents to treat AML.

Topics: Animals; Antineoplastic Agents; Aurora Kinase B; Cell Line, Tumor; Chlorocebus aethiops; Drug Design; fms-Like Tyrosine Kinase 3; Humans; Indoles; Leukemia, Myeloid, Acute; Male; Mice; Protein Kinase Inhibitors; Vero Cells; Xenograft Model Antitumor Assays

In acute myelogenous leukemia (AML), the FLT3 receptor tyrosine kinase (RTK) is highly expressed with 30% of patients expressing a mutated, constitutively active form of this protein. To inhibit this receptor, VX-322 was developed and found to be very potent against both the FLT3 and c-KIT RTKs with enzyme K(i) values of <1 nM and a cellular IC(50) between 1 and 5 nM. It was efficacious in a FLT3-ITD dependent myeloproliferative mouse model, doubling survival compared to other FLT3 inhibitors, with 25% of the mice cured. Upon treatment of primary AML patient blast cells, the dual inhibition of FLT3 and c-KIT was superior to inhibitors targeting a single RTK. Thus, this compound may represent an improved pharmacologic and selectivity profile that could be effective in the treatment of AML.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Survival; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Male; Mice; Mice, Inbred BALB C; Morpholines; Neoplasm Transplantation; Proto-Oncogene Proteins c-kit; Serum; Triazoles; Tumor Cells, Cultured

Structure-activity relationship (SAR) studies of 2-(quinazolin-4-ylthio)thiazole derivatives, which are for optimizing the in vitro and in vivo antiacute myeloid leukemia (AML) activity of a previously identified FLT3 inhibitor 2-(6,7-dimethoxyquinazolin-4-ylthio)thiazole (1), are described. SAR studies centering around the head (thiazole) and tails (6- and 7-positions) of the quinazoline moiety of 1 led to the discovery of a series of compounds that exhibited significantly increased potency against FLT3-driven AML MV4-11 cells. Preliminary in vivo assays were carried out on three highly active compounds, whose results showed that 1-{5-[7-(3-morpholinopropoxy)quinazolin-4-ylthio]-[1,3,4]thiadiazol-2-yl}-3-p-tolylurea (20c) had the highest in vivo activity. Further in vitro and in vivo anti-AML studies were then performed on 20c; in an MV4-11 xenograft mouse model, a once-daily dose of 20c at 100 mg/kg for 18 days led to complete tumor regression without obvious toxicity. Western blot and immunohistochemical analysis were carried out to illustrate the mechanism of action of 20c.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Drug Design; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Mice; Phenylurea Compounds; Quinazolines; Structure-Activity Relationship; Thiadiazoles; Xenograft Model Antitumor Assays

A series of azulene-based derivatives were synthesized as potent inhibitors for receptor tyrosine kinases such as FMS-like tyrosine kinase 3 (FLT-3). Systematic side chain modification of prototype 1a was carried out through SAR studies. Analogue 22 was identified from this series and found to be one of the most potent FLT-3 inhibitors, with good pharmaceutical properties, superior efficacy, and tolerability in a tumor xenograft model.

Topics: Animals; Antineoplastic Agents; Azulenes; Cell Line, Tumor; Cell Proliferation; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Mice; Mice, Inbred BALB C; Mice, Nude; Rats; Receptor Protein-Tyrosine Kinases

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.

Topics: Animals; Benzenesulfonates; Benzothiazoles; Bone Marrow; Carbazoles; Cell Line, Tumor; Cell Proliferation; Female; fms-Like Tyrosine Kinase 3; Furans; Humans; Leukemia, Myeloid, Acute; Mice; Mice, Nude; Mice, SCID; Niacinamide; Phenylurea Compounds; Phosphorylation; Piperazines; Prognosis; Protein Interaction Mapping; Protein Kinase C; Protein Kinase Inhibitors; Pyridines; Quinazolines; Sorafenib; Staurosporine; Xenograft Model Antitumor Assays