Acute myeloid leukemia (AML), a heterogeneous hematologic malignancy, has generally a poor prognosis despite the recent advancements in diagnostics and treatment. Genetic instability, particularly mutations in the FMS-like tyrosine kinase 3 (FLT3) gene, is associated with severe outcomes. Approximately 30 % of AML patients harbor FLT3 mutations, which have been linked to higher relapse and reduced survival rates. Traditional AML treatments employ cytarabine and anthracyclines drugs. Furthermore, the development of FLT3 inhibitors has significantly improved therapy for FLT3-mutated AML patients. For example, the introduction of midostaurin, the first FLT3 inhibitor, improved patient outcomes. However, resistant AML cell clones continue to pose a challenge to the success of AML treatment. This review discusses FLT3 kinase, mutations, and role in AML pathogenesis. It explores the molecular mechanisms of FLT3 activation, signaling pathways, and the structure and function of the FLT3 receptor. Current and emerging therapeutic approaches are presented, while highlighting the latest FLT3 inhibitors in clinical use, and strategies to overcome drug resistance. Future directions, including personalized therapies and novel drug designs, are examined to provide updated insights into FLT3-targeted treatments. This comprehensive review aims to guide clinicians and researchers in the development of innovative therapies to improve AML patient outcomes.

• MeSH
• akutní myeloidní leukemie * farmakoterapie   genetika   MeSH
• chemorezistence účinky léků   MeSH
• cílená molekulární terapie * MeSH
• inhibitory proteinkinas * terapeutické užití   farmakologie   MeSH
• lidé MeSH
• mutace MeSH
• protinádorové látky terapeutické užití   farmakologie   MeSH
• signální transdukce účinky léků   MeSH
• tyrosinkinasa 3 podobná fms * antagonisté a inhibitory   genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: The genetic and epigenetic alterations observed in acute myeloid leukemia (AML) contribute to its heterogeneity, influencing disease progression response to therapy, and patient outcomes. The use of antisense oligonucleotides (ASOs) technology allows for the design of oligonucleotide inhibitors based on gene sequence information alone, enabling precise targeting of key molecular pathways or specific genes implicated in AML. METHODS AND RESULTS: Midostaurin, a FLT3 specific inhibitor and ASOs targeting particular genes, exons, or mutations was conducted using AML models. This ASOs treatment was designed to bind to exon 7 of the MBNL1 (muscleblind-like) gene. Another target was the FLT3 gene, focusing on two aspects: (a) FLT3-ITD (internal tandem duplication), to inhibit the expression of this aberrant gene form, and (b) the FLT3 in general. Treated and untreated cells were analyzed using quantitative PCR (qPCR), dot blot, and Raman spectroscopy. This study contrasts midostaurin with ASOs that inhibit FLT3 protein production or its isoforms via mRNA degradation. A trend of increased FLT3 expression was observed in midostaurin-treated cells, while ASO-treated cells showed decreased expression, though these changes were not statistically significant. CONCLUSIONS: In AML, exon 7 of MBNL1 is involved in several cellular processes and in this study, exon 7 of MBNL1 was targeted for method optimization, with the highest block of the exon 7 gene variant observed 48 h post-transfection. Midostaurin, a multitargeted kinase inhibitor, acts against the receptor tyrosine kinase FLT3, a critical molecule in AML pathogenesis. While midostaurin blocks FLT3 signaling pathways, it paradoxically increases FLT3 expression.

• MeSH
• akutní myeloidní leukemie * genetika   farmakoterapie   MeSH
• antisense oligonukleotidy * farmakologie   genetika   MeSH
• exony genetika   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• proteiny vázající RNA genetika   metabolismus   MeSH
• regulace genové exprese u leukemie účinky léků   MeSH
• staurosporin * analogy a deriváty   farmakologie   MeSH
• tyrosinkinasa 3 podobná fms * genetika   antagonisté a inhibitory   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

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.

• MeSH
• akutní myeloidní leukemie farmakoterapie   patologie   metabolismus   MeSH
• inhibitory proteinkinas * farmakologie   chemie   chemická syntéza   MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky * farmakologie   chemie   chemická syntéza   MeSH
• pyrimidiny chemie   farmakologie   chemická syntéza   MeSH
• screeningové testy protinádorových léčiv * 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

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.

• 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

Midostaurin is an FMS-like tyrosine kinase 3 receptor (FLT3) inhibitor that provides renewed hope for treating acute myeloid leukaemia (AML). The limited efficacy of this compound as a monotherapy contrasts with that of its synergistic combination with standard cytarabine and daunorubicin (Dau), suggesting a therapeutic benefit that is not driven only by FLT3 inhibition. In an AML context, the activity of the enzyme aldo-keto reductase 1C3 (AKR1C3) is a crucial factor in chemotherapy resistance, as it mediates the intracellular transformation of anthracyclines to less active hydroxy metabolites. Here, we report that midostaurin is a potent inhibitor of Dau inactivation mediated by AKR1C3 in both its recombinant form as well as during its overexpression in a transfected cell model. Likewise, in the FLT3- AML cell line KG1a, midostaurin was able to increase the cellular accumulation of Dau and significantly decrease its metabolism by AKR1C3 simultaneously. The combination of those mechanisms increased the nuclear localization of Dau, thus synergizing its cytotoxic effects on KG1a cells. Our results provide new in vitro evidence of how the therapeutic activity of midostaurin could operate beyond targeting the FLT3 receptor.

• MeSH
• akutní myeloidní leukemie farmakoterapie   enzymologie   genetika   patologie   MeSH
• biotransformace MeSH
• daunomycin metabolismus   farmakologie   MeSH
• HCT116 buňky MeSH
• inhibitory enzymů farmakologie   MeSH
• kolorektální nádory farmakoterapie   enzymologie   genetika   patologie   MeSH
• lidé MeSH
• protein AKR1C3 antagonisté a inhibitory   genetika   metabolismus   MeSH
• protokoly protinádorové kombinované chemoterapie farmakologie   MeSH
• staurosporin analogy a deriváty   farmakologie   MeSH
• synergismus léků MeSH
• tyrosinkinasa 3 podobná fms antagonisté a inhibitory   genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The 3H-pyrazolo[4,3-f]quinoline moiety has been recently shown to be a privileged kinase inhibitor core with potent activities against acute myeloid leukemia (AML) cell lines in vitro. Herein, various 3H-pyrazolo[4,3-f]quinoline-containing compounds were rapidly assembled via the Doebner-Povarov multicomponent reaction from the readily available 5-aminoindazole, ketones, and heteroaromatic aldehydes in good yields. The most active compounds potently inhibit the recombinant FLT3 kinase and its mutant forms with nanomolar IC50 values. Docking studies with the FLT3 kinase showed a type I binding mode, where the 3H-pyrazolo group interacts with Cys694 in the hinge region. The compounds blocked the proliferation of AML cell lines harboring oncogenic FLT3-ITD mutations with remarkable IC50 values, which were comparable to the approved FLT3 inhibitor quizartinib. The compounds also inhibited the growth of leukemia in a mouse-disseminated AML model, and hence, the novel 3H-pyrazolo[4,3-f]quinoline-containing kinase inhibitors are potential lead compounds to develop into anticancer agents, especially for kinase-driven cancers.

• MeSH
• akutní myeloidní leukemie farmakoterapie   metabolismus   patologie   MeSH
• inhibitory proteinkinas chemická syntéza   chemie   farmakologie   MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buňky kultivované MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky chemická syntéza   chemie   farmakologie   MeSH
• screeningové testy protinádorových léčiv 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
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

OBJECTIVES: Interaction of leukemia cells with the bone marrow extracellular matrix promotes cell survival and resistance to chemotherapy. In this work, we analyzed integrin expression and adhesivity to fibronectin in primary cells from patients with acute myeloid leukemia. METHODS: Surface expression of integrins β1 and αVβ3 on primary leukemia cells (N = 46) was correlated with the stem cell marker CD34, as well as with cell adhesivity to fibronectin. The results were analyzed with regard to the mutational status of NPM1 and FLT3 genes. RESULTS: The integrin β1 was omnipresent, whereas αVβ3 was often more expressed on CD34-positive cells. In particular, higher αVβ3 expression on CD34+ cells was associated with NPM1 mutation (P = .0018). Monocytic leukemias had significantly higher αVβ3 expression compared to less maturated cases (P = .0008). Cells from patients with internal tandem duplications in FLT3 (FLT3-ITD) had lower adhesivity to fibronectin compared to cells with wild-type FLT3 (P = .031), specifically in less differentiated myeloblasts. Inhibition of a putative FLT3-ITD target, EZH2, increased cell adhesivity in MV4-11 cell line (P = .024). CONCLUSIONS: The integrin αVβ3 is expressed in particular on CD34+ cells with NPM1 mutation and might have a prognostic value in patients with mutated NPM1. FLT3-ITD is associated with lower cell adhesivity, especially in patients with less differentiated leukemias.

• MeSH
• akutní myeloidní leukemie genetika   metabolismus   MeSH
• buněčná adheze MeSH
• buněčná membrána metabolismus   MeSH
• duplikace genu MeSH
• exprese genu MeSH
• fibronektiny metabolismus   MeSH
• integriny genetika   metabolismus   MeSH
• jaderné proteiny genetika   metabolismus   MeSH
• lidé MeSH
• mutace MeSH
• nádorové buněčné linie MeSH
• tyrosinkinasa 3 podobná fms genetika   metabolismus   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

FLT3 tyrosine kinase is a potential drug target in acute myeloid leukemia (AML) because patients with FLT3-ITD mutations respond poorly to standard cytotoxic agents and there is a clear link between the disease and the oncogenic properties of FLT3. We present novel 2,6,9-trisubstituted purine derivatives with potent FLT3 inhibitory activity. The lead compound 7d displays nanomolar activity in biochemical assays and selectively blocks proliferation of AML cell lines harboring FLT3-ITD mutations, whereas other transformed and normal human cells are several orders of magnitude less sensitive. The MV4-11 cells treated with 7d suppressed the phosphorylation of FLT3 and its downstream signaling pathways, with subsequent G1 cell cycle arrest and apoptosis. Additionally, a single dose of 7d in mice with subcutaneous MV4-11 xenografts caused sustained inhibition of FLT3 and STAT5 phosphorylation over 48 h, in contrast to the shorter effect observed after administration of the reference FLT3 inhibitor quizartinib.

• MeSH
• akutní myeloidní leukemie genetika   patologie   MeSH
• diaminy chemie   metabolismus   farmakologie   MeSH
• inhibitory proteinkinas chemie   metabolismus   farmakologie   MeSH
• konformace proteinů MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• objevování léků * MeSH
• protinádorové látky chemie   metabolismus   farmakologie   MeSH
• simulace molekulového dockingu MeSH
• tyrosinkinasa 3 podobná fms antagonisté a inhibitory   chemie   genetika   metabolismus   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The optimal timing of allogeneic hematopoietic stem cell transplantation (HCT) in acute myeloid leukemia (AML) is controversial. We report on 1179 patients with a median age of 48 years who were randomized upfront. In the control arm, sibling HCT was scheduled in the first complete remission for intermediate-risk or high-risk AML and matched unrelated HCT in complex karyotype AML. In the experimental arm, matched unrelated HCT in first remission was offered also to patients with an FLT3-ITD (FMS-like tyrosine kinase 3-internal tandem duplication) allelic ratio >0.8, poor day +15 marrow blast clearance and adverse karyotypes. Further, allogeneic HCT was recommended in high-risk AML to be performed in aplasia after induction chemotherapy. In the intent-to-treat (ITT) analysis, superiority of the experimental transplant strategy could not be shown with respect to overall survival (OS) or event-free survival. As-treated analyses suggest a profound effect of allogeneic HCT on OS (HR 0.73; P=0.002) and event-free survival (HR 0.67; P<0.001). In high-risk patients, OS was significantly improved after allogeneic HCT in aplasia (HR 0.64; P=0.046) and after HCT in remission (HR 0.74; P=0.03). Although superiority of one study arm could not be demonstrated in the ITT analysis, secondary analyses suggest that early allogeneic HCT is a promising strategy for patients with high-risk AML.

• MeSH
• akutní myeloidní leukemie genetika   terapie   MeSH
• alely MeSH
• dospělí MeSH
• homologní transplantace MeSH
• indukce remise MeSH
• Kaplanův-Meierův odhad MeSH
• karyotypizace MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• přežití bez známek nemoci MeSH
• recidiva MeSH
• regulace genové exprese u leukemie MeSH
• transplantace hematopoetických kmenových buněk * MeSH
• tyrosinkinasa 3 podobná fms genetika   metabolismus   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

OBJECTIVES: Recently, mutations in DNMT3A gene have been described in about 25% acute myeloid leukemia (AML) cases, preferentially in monocytic AML. They were found to predict worse overall survival (OS) of mutated patients. PATIENTS AND METHODS: RT-PCR followed by direct sequencing was used to test the presence of DNMT3A mutations in 226 AML patients with an intermediate-risk (IR) cytogenetics. RESULTS: Sixty-seven patients of 226 (29.6%) carried a mutation in the DNMT3A gene. Occurrence of DNMT3A mutations was associated with female sex (P = 0.027) and with the presence of FLT3/ITD (P = 0.003), but not with particular FAB subtypes. Patients with DNMT3A mutation had higher initial WBC counts than those without it (P = 0.064) only because of higher incidence of FLT3/ITD within these cases. There was no difference between mutated and wild-type groups in reaching complete remission (CR) (P = 0.380). OS was not affected by DNMT3A mutation (P = 0.251), but OS of patients who reached CR was longer in DNMT3A negative cases (P = 0.025). Patients with DNMT3A mutation had a higher relapse rate (P = 0.007). Patients carrying both the DNMT3A mutation and FLT3/ITD relapsed more often than either patients with single DNMT3A mutation (P = 0.044) or patients with FLT3/ITD only (P = 0.058). DNMT3A mutations were associated with higher relapse rate even within the FLT3/ITD-negative group (P = 0.072). After reaching CR, these two genetic factors were independent predictors of relapse at multivariate analysis (P < 0.001). Only three of 30 'double-mutated' (FLT3/ITD+, DNMT3A+) patients are still alive, all of them having undergone hematopoietic stem cell transplant. CONCLUSIONS: We have confirmed the high incidence of DNMT3A mutations in patients with AML with IR cytogenetics. Patients with DNMT3A mutations relapse more often and have inferior OS when only patients achieving CR are analyzed. 'Double-mutated' patients have a very poor prognosis.

• MeSH
• akutní myeloidní leukemie genetika   mortalita   MeSH
• chromozomální aberace MeSH
• DNA-(cytosin-5-)methyltransferasa genetika   MeSH
• dospělí MeSH
• incidence MeSH
• indukce remise MeSH
• Kaplanův-Meierův odhad MeSH
• kodon MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace MeSH
• prognóza MeSH
• recidiva MeSH
• rizikové faktory MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• tyrosinkinasa 3 podobná fms metabolismus   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH