Given the significant prevalence of FLT3 receptor and its mutations in acute myeloid leukemia (AML) pathogenesis, we present a novel series of furo[2,3-d]pyrimidin-1,3,4-thiadiazole-urea derivatives, designed to exhibit FLT3-ITD inhibitory activity. These compounds demonstrated cytotoxicity in FLT3-ITD expressing AML cell lines MOLM-13 and MV4-11 in the nanomolar range, with significant selectivity over the K562 cell line. In-depth evaluations of example compound 49 revealed its efficacy in suppressing FLT3 phosphorylation and the downstream signaling molecules, including STAT5 and ERK1/2. Notably, compound 49 demonstrated cytotoxic effects in Ba/F3 cells expressing FLT3-ITD or FLT3-ITD-F691L mutant, exceeding the potency of both sorafenib and quizartinib. Molecular docking studies suggest that this compound binds to the active site of FLT3 in a type II manner. The study suggests that substituted furo[2,3-d]pyrimidines could be useful additions to the growing field of FLT3-targeted therapy for AML. These compounds have the potential to serve as novel FLT3-ITD inhibitors and may offer insights for developing future therapeutic strategies in AML.

• Klíčová slova
• 1,3,4-thiadiazole, AML, FLT3-ITD inhibitors, furo[2,3-d]pyrimidine, urea,
• MeSH
• akutní myeloidní leukemie farmakoterapie   patologie   metabolismus   MeSH
• antitumorózní látky * farmakologie   chemie   chemická syntéza   MeSH
• inhibitory proteinkinas * farmakologie   chemie   chemická syntéza   MeSH
• léky antitumorózní - screeningové testy * MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• pyrimidiny chemie   farmakologie   chemická syntéza   MeSH
• simulace molekulového dockingu * MeSH
• thiadiazoly * chemie   farmakologie   chemická syntéza   MeSH
• tyrosinkinasa 3 podobná fms * antagonisté a inhibitory   metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 1,3,4-thiadiazole MeSH Prohlížeč
• antitumorózní látky * MeSH
• FLT3 protein, human MeSH Prohlížeč
• inhibitory proteinkinas * MeSH
• pyrimidiny MeSH
• thiadiazoly * MeSH
• tyrosinkinasa 3 podobná fms * MeSH

Allogeneic hematopoietic cell transplantation (alloHCT) as a postremission therapy in patients with FLT3-ITD-positive intermediate-risk acute myeloid leukemia (AML) remains controversial. FLT3-ITD mutations are heterogeneous with respect to allelic ratio, location, and length of the insertion, with a high mutant-to-wild-type ratio consistently associated with inferior prognosis. We retrospectively analyzed the role of alloHCT in first remission in relationship to the allelic ratio and presence or absence of nucleophosmin 1 mutations (NPM1) in the Study Alliance Leukemia AML2003 trial. FLT3-ITD mutations were detected in 209 patients and concomitant NPM1 mutations in 148 patients. Applying a predefined cutoff ratio of .8, AML was grouped into high- and low-ratio FLT3-ITD AML (HR(FLT3-ITD) and LR(FLT3-ITD)). Sixty-one patients (29%) were transplanted in first remission. Overall survival (OS) (HR, .3; 95% CI, .16 to .7; P = .004) and event-free survival (EFS) (HR, .4; 95% CI, .16 to .9; P = .02) were significantly increased in patients with HR(FLT3-ITD) AML who received alloHCT as consolidation treatment compared with patients who received consolidation chemotherapy. Patients with LR(FLT3-ITD) AML and wild-type NPM1 who received alloHCT in first remission had increased OS (HR, .3; 95% CI, .1 to .8; P = .02) and EFS (HR, .2; 95% CI, .1 to .8; P = .02), whereas alloHCT in first remission did not have a significant impact on OS and EFS in patients with LR(FLT3-ITD) AML and concomitant NPM1 mutation. In conclusion, our results provide additional evidence that alloHCT in first remission improves EFS and OS in patients with HR(FLT3-ITD) AML and in patients with LR(FLT3-ITD) AML and wild-type NPM1.

• Klíčová slova
• Acute myeloid leukemia, Allogeneic transplantation, FLT3-ITD, NPM1 mutation,
• MeSH
• akutní myeloidní leukemie * enzymologie   genetika   mortalita   terapie   MeSH
• alely * MeSH
• alografty MeSH
• dospělí MeSH
• jaderné proteiny genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• míra přežití MeSH
• mladiství MeSH
• mutace * MeSH
• nukleofosmin MeSH
• přežití po terapii bez příznaků nemoci MeSH
• transplantace kmenových buněk * MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH
• tyrosinkinasa 3 podobná fms MeSH

BACKGROUND: Patients with internal tandem duplication in fms-related tyrosine kinase receptor gene 3 (FLT3-ITD)-mutated acute myeloid leukemia (AML) have a dismal prognosis and the only curative option seems to be allogeneic stem cell transplantation (alloSCT). However, its timing is still matter of debate. PATIENTS AND METHODS: We retrospectively analyzed 73 consecutive AML patients with FLT3-ITD (median age 53, range 20-68 years) allografted with consistent policy to try to refer them all for upfront alloSCT in first complete remission (CR1). RESULTS: With a median follow-up of 44 (range, 5-135) months the 5-year overall survival (OS)/disease-free survival (DFS) probabilities were 49%/47%. The cumulative incidence of relapse and nonrelapse mortality (NRM) were 37% and 14%, respectively. The estimated 5-year OS for patients who received transplantation in CR1 was 62% versus 0% for patients who received transplantation beyond CR1. Multivariable analysis identified stem cell transplantation beyond CR1 as the key factor for poor OS (hazard ratio [HR], 5.41; P < .0001), DFS (HR, 4.41; P = .0002), and high relapse incidence (HR, 8.08; P < .0001). Acute graft versus host disease Grade ≥3 predicted higher NRM (HR, 3.80; P = .059) as well as inferior OS (HR, 2.04; P = .0079). No association of patient age, nucleophosmin status, donor type, conditioning, and other variables on the survival was detected. CONCLUSION: AlloSCT should be regarded with urgency as soon as CR1 is achieved in this subset of AML patients.

• Klíčová slova
• AML, Allogeneic SCT, Complete remission, Donor, FLT3-ITD,
• MeSH
• akutní myeloidní leukemie diagnóza   genetika   mortalita   terapie   MeSH
• dárci tkání MeSH
• dospělí MeSH
• duplikace genu * MeSH
• homologní transplantace MeSH
• indukce remise MeSH
• kombinovaná terapie MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mutace * MeSH
• prognóza MeSH
• recidiva MeSH
• retrospektivní studie MeSH
• senioři MeSH
• transplantace hematopoetických kmenových buněk * škodlivé účinky   metody   MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• tyrosinkinasa 3 podobná fms MeSH

OBJECTIVES: Acute myeloid leukemia (AML) cells are highly resistant to therapy. The presumed molecular basis of this resistance is the effect of tumor necrosis factor alpha (TNF-α) and other cytokines on endothelial adhesion molecule expression. The aim of this study was to test the hypothesis that cytokines and soluble adhesion molecules correlate in AML. METHODS: Baseline serum levels of 17 cytokines and 5 soluble adhesion molecules were measured in 53 AML patients using biochip array technology. Age, leukocyte count, secondary AML, CRP, FLT3-ITD and remission were variables. Statistical analysis was performed in R version 3.1.2. RESULTS: VCAM-1 correlated with ICAM-1 (P < 0.0001), E-selectin (P < 0.0001), leukocyte count (P = 0.0005) and TNF-α (P = 0.0035). E-selectin correlated with leukocyte count (P < 0.0001), P-selectin (P = 0.0032) and MCP-1 (P = 0.0119). CRP correlated with IL-6 (P < 0.0001), leukocyte count negatively correlated with IL-7 (P = 0.0318). FLT3-ITD was associated with higher E-selectin (P = 0.0010) and lower IL-7 (P = 0.0252). Secondary AML patients were older. Failure of induction therapy was associated with significantly higher CRP and lower P-selectin. Leukocyte count (P < 0.0001), FLT3-ITD (P = 0.0017) and secondary AML (P = 0.0439) influenced the principal component. CONCLUSIONS: Leukemic cells can modulate the microenvironment. Cytokine, adhesion molecule levels and leukocyte count correlate in AML. Understanding these mechanisms may form the basis of novel therapeutic approaches.

• Klíčová slova
• FLT3-ITD, TNF-alpha, acute myeloid leukemia, adhesion molecules, cytokines,
• MeSH
• akutní myeloidní leukemie krev   farmakoterapie   MeSH
• analýza hlavních komponent MeSH
• chemorezistence MeSH
• cytokiny metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• molekuly buněčné adheze metabolismus   MeSH
• počet leukocytů MeSH
• prospektivní studie MeSH
• protokoly antitumorózní kombinované chemoterapie terapeutické užití   MeSH
• TNF-alfa fyziologie   MeSH
• tyrosinkinasa 3 podobná fms fyziologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cytokiny MeSH
• FLT3 protein, human MeSH Prohlížeč
• molekuly buněčné adheze MeSH
• TNF-alfa MeSH
• tyrosinkinasa 3 podobná fms MeSH

Nucleophosmin-1 (NPM1) mutations in acute myeloid leukemia (AML) confer a survival advantage in the absence of FLT3-internal tandem duplication (FLT3-ITD). Here, we investigated the main predictors of outcome after allogeneic hematopoietic stem cell transplantation (allo-HCT). We identified 1572 adult (age ≥ 18 year) patients with NPM1-mutated AML in first complete remission (CR1:78%) or second complete remission (CR2:22%) who were transplanted from matched sibling donors (30.8%) or unrelated donors (57.4%) between 2007 and 2019 at EBMT participating centers. Median follow-up for survivors was 23.7 months. FLT3-ITD was present in 69.3% of patients and 39.2% had detectable minimal/measurable residual disease (MRD) at transplant. In multivariate analysis, relapse incidence (RI) and leukemia-free survival (LFS) were negatively affected by concomitant FLT3-ITD mutation (HR 1.66 p = 0.0001, and HR 1.53, p < 0.0001, respectively), MRD positivity at transplant (HR 2.18, p < 10-5 and HR 1.71, p < 10-5 , respectively), and transplant in CR2 (HR 1.36, p = 0.026, and HR 1.26, p = 0.033, respectively), but positively affected by Karnofsky score ≥90 (HR 0.74, p = 0.012, and HR 0.7, p = 0.0002, respectively). Overall survival (OS) was also negatively influenced by concomitant FLT3-ITD (HR 1.6, p = 0.0001), MRD positivity at transplant (HR 1.61, p < 10-5 ), and older age (HR 1.22 per 10 years, p < 0.0001), but positively affected by matched sibling donor (unrelated donor: HR 1.35, p = 0.012; haploidentical donor: HR 1.45, p = 0.037) and Karnofsky score ≥90 (HR 0.73, p = 0.004). These results highlight the independent and significant role of FLT3-ITD, MRD status, and disease status on posttransplant outcomes in patients with NPM1-mutated AML allowing physicians to identify patients at risk of relapse who may benefit from posttransplant prophylactic interventions.

• Klíčová slova
• FLT3-ITD, NPM-1 mutation, acute myeloid leukemia, minimal residual disease,
• MeSH
• akutní myeloidní leukemie * genetika   terapie   MeSH
• dospělí MeSH
• lidé MeSH
• mutace MeSH
• nukleofosmin MeSH
• prognóza MeSH
• recidiva MeSH
• retrospektivní studie MeSH
• transplantace hematopoetických kmenových buněk * metody   MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• nukleofosmin MeSH
• tyrosinkinasa 3 podobná fms MeSH

Oncogenic mutations in gene encoding FLT3 kinase are often detected in acute myeloid leukaemia (AML) patients, and several potent kinase inhibitors have been developed. However, the FLT3 inhibitor treatment often leads to the resistance development and subsequent relapse. Targeted degradation of oncogenic protein kinases has emerged as a feasible pharmacological strategy, providing more robust effect over traditional competitive inhibitors. Based on previously developed competitive inhibitor of FLT3 and CDK9, we have designed and prepared a novel pomalidomide-based PROTAC. A series of biochemical and cellular experiments showed selectivity towards FLT3-ITD bearing AML cells and confirmed proteasome-dependent mechanism of action. Dual FLT3-ITD and CDK9 protein degradation resulted in the block of FLT3-ITD downstream signalling pathways, apoptosis activation and cell cycle arrest of FLT3-ITD AML cells. Moreover, transcriptional repression caused by CDK9 degradation significantly reduced expression of crucial genes involved in AML pathogenesis. The obtained results indicate the beneficial impact of simultaneous FLT3-ITD/CDK9 degradation for AML therapy.

• Klíčová slova
• Acute myeloid leukaemia, CDK9, FLT3, Proteolysis targeting chimera (PROTAC),
• MeSH
• akutní myeloidní leukemie * patologie   MeSH
• apoptóza MeSH
• cyklin-dependentní kinasa 9 metabolismus   MeSH
• inhibitory proteinkinas farmakologie   terapeutické užití   MeSH
• lidé MeSH
• mutace MeSH
• proteolýza MeSH
• tyrosinkinasa 3 podobná fms genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• CDK9 protein, human MeSH Prohlížeč
• cyklin-dependentní kinasa 9 MeSH
• FLT3 protein, human MeSH Prohlížeč
• inhibitory proteinkinas MeSH
• tyrosinkinasa 3 podobná fms MeSH

FLT3 is the most frequently mutated gene in acute myeloid leukemia (AML), with internal tandem duplications (ITDs) accounting for up to 30% of its mutations. To analyze the impact of individual ITDs on the expression profile of immature myeloid cells, we have established 32D cell lines expressing nine different FLT3/ITDs isolated from AML patients and subjected them to whole genome expression profiling and 2DE/LC/MS proteomics. Our data indicate that in comparison to the controls, FLT3/ITD-positive 32D cells exhibit less mature expression profiles resembling early hematopoietic progenitors. Moreover, our results suggest that there exist biological differences among individual ITD variants.

• MeSH
• akutní myeloidní leukemie genetika   patologie   MeSH
• blastická krize genetika   patologie   MeSH
• buněčná diferenciace MeSH
• buněčné dělení MeSH
• exony MeSH
• genetická variace * MeSH
• klonování DNA MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• mutace MeSH
• myši genetika   MeSH
• nádorové buněčné linie MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• Retroviridae genetika   MeSH
• sekvence aminokyselin MeSH
• sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
• stanovení celkové genové exprese MeSH
• tandemové repetitivní sekvence genetika   MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši genetika   MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• tyrosinkinasa 3 podobná fms MeSH

FLT3 kinase is a potential drug target in acute myeloid leukemia (AML). Patients with FLT3 mutations typically have higher relapse rates and worse outcomes than patients without FLT3 mutations. In this study, we investigated the suitability of various heterocycles as central cores of FLT3 inhibitors, including thieno[3,2-d]pyrimidine, pyrazolo[1,5-a]pyrimidine, imidazo[4,5-b]pyridine, pyrido[4,3-d]pyrimidine, and imidazo[1,2-b]pyridazine. Our assays revealed a series of imidazo[1,2-b]pyridazines with high potency against FLT3. Compound 34f showed nanomolar inhibitory activity against recombinant FLT3-ITD and FLT3-D835Y (IC50 values 4 and 1 nM, respectively) as well as in the FLT3-ITD-positive AML cell lines MV4-11, MOLM-13, and MOLM-13 expressing the FLT3-ITD-D835Y mutant (GI50 values of 7, 9, and 4 nM, respectively). In contrast, FLT3-independent cell lines were much less sensitive. In vitro experiments confirmed suppression of FLT3 downstream signaling pathways. Finally, the treatment of MV4-11 xenograft-bearing mice with 34f at doses of 5 and 10 mg/kg markedly blocked tumor growth without any adverse effects.

• MeSH
• akutní myeloidní leukemie * patologie   MeSH
• antitumorózní látky * farmakologie   terapeutické užití   MeSH
• apoptóza MeSH
• inhibitory proteinkinas farmakologie   terapeutické užití   MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• pyridaziny * farmakologie   terapeutické užití   MeSH
• pyrimidiny farmakologie   MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antitumorózní látky * MeSH
• FLT3 protein, human MeSH Prohlížeč
• inhibitory proteinkinas MeSH
• pyridazine MeSH Prohlížeč
• pyridaziny * MeSH
• pyrimidiny MeSH
• tyrosinkinasa 3 podobná fms MeSH

The aim of this study was to evaluate the prognostic impact of FLT3-ITD in core-binding factor acute myeloid leukemia (CBFAML) in an international, multicenter survey of 97 patients of whom 52% had t(8;21)(q22;q22) and 48% had inv(16)(p13q22)/t(16;16)(p13;q22). The median age of the patients was 53 years (range, 19-81). Complete remission after anthracycline-based induction (n=86) and non-intensive therapy (n=11) was achieved in 97% and 36% of the patients, respectively. The median follow-up was 4.43 years (95% confidence interval [95% CI]: 3.35-7.39 years). The median survival after intensive and non-intensive treatment was not reached and 0.96 years, respectively. Among intensively treated patients, inv(16) with trisomy 22 (n=11) was associated with a favorable 4-year relapse-free survival rate of 80% (95% CI: 59-100%) as compared to 38% (95% CI: 27-54%; P=0.02) in all other patients with CBFAML/ FLT3-ITD (n=75). Overall, 24 patients underwent allogeneic hematopoietic cell transplantation (HCT), 12 in first complete remission and 12 after relapse. Allogeneic HCT in first complete remission was not beneficial (P=0.60); however, allogeneic HCT seemed to improve median survival in relapsed patients compared to that of patients treated with chemotherapy (not reached vs. 0.6 years, respectively; P=0.002). Excluding patients with inv(16) with trisomy 22, our data indicate that compathe outcome of CBF-AML patients with FLT3-ITD may be inferior to that of patients without FLT3-ITD (based on previously published data), suggesting that prognostically CBF-AML patients with FLT3-ITD should not be classified as favorable-risk. FLT3-inhibitors may improve the outcome of these patients.

• MeSH
• akutní myeloidní leukemie * diagnóza   genetika   terapie   MeSH
• dospělí MeSH
• indukce remise MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mutace MeSH
• prognóza MeSH
• retrospektivní studie MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• transkripční faktor PEBP2 genetika   MeSH
• transplantace hematopoetických kmenových buněk * MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• transkripční faktor PEBP2 MeSH
• tyrosinkinasa 3 podobná fms MeSH

Therapy of FLT3-positive acute myeloid leukemia still remains complicated, despite the availability of newly approved kinase inhibitors. Various strategies to avoid the reduced efficacy of therapy have been explored, including the development of dual targeting compounds, which inhibit FLT3 and another kinase necessary for the survival and proliferation of AML cells. We have designed new 2,7,9-trisubstituted 8-oxopurines as FLT3 inhibitors and report here the structure-activity relationship studies. We demonstrated that substituents at positions 7 and 9 modulate activity between CDK4 and FLT3 kinase, and the isopropyl group at position 7 substantially increased the selectivity toward FLT3 kinase, which led to the discovery of compound 15a (9-cyclopentyl-7-isopropyl-2-((4-(piperazin-1-yl)phenyl)amino)-7,9-dihydro-8H-purin-8-one). Cellular analyses in MV4-11 cells revealed inhibition of autophosphorylation of FLT3 kinase in nanomolar doses, including the suppression of downstream STAT5 and ERK1/2 phosphorylation. We also describe mechanistic studies in cell lines and activity in a mouse xenograft model in vivo.

• Klíčová slova
• FLT3, acute myeloid leukemia, cyclin-dependent kinase, inhibitor, purine,
• MeSH
• akutní myeloidní leukemie * farmakoterapie   MeSH
• apoptóza MeSH
• fosforylace MeSH
• inhibitory proteinkinas terapeutické užití   MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• proliferace buněk MeSH
• tyrosinkinasa 3 podobná fms MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• inhibitory proteinkinas MeSH
• tyrosinkinasa 3 podobná fms MeSH