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ITDs and D835 mutations in the FLT3 gene in patients with AML M0. (a) Primer pairs for RT-PCR analysis of ITD and D835 mutations. First amino-acid number of the each domain is given above the diagram. TM: transmembrane, JM: juxtamembrane, TK1: first tyrosine kinase, TK2: second tyrosine kinase domain (b) Gel electrophoresis showed FLT3-ITD mutations. Arrows and arrow heads showed wild types (WTs) and duplications of the FLT3 gene, respectively. Lane numbers correspond to patient numbers in Table 1. M showed a 100 bp DNA ladder. (c) Restriction fragment length polymorphism-mediated RT-PCR assay showed FLT3-D835 mutations. Digestion of the wild-type PCR products with EcoRV yields 308 and 172 bp bands (arrows), whereas mutated FLT3 gene generates only a 480 bp fragment (arrow head). (d) Patient #7 showed FLT3-ITD and FLT3-D835 mutations in different alleles. Amplifications of exons 12–22 of the FLT3 gene including the region from JM through TK2 domains by RT-PCR using FL-R5 and FL-MR2 primers were digested by EcoRV. HL-60 was served as a control in lanes 1 and 2. PCR products from patient #7 were subjected in lanes 3 and 4. PCR products in lanes 2 and 4 were digested by EcoRV, but not in lanes 1 and 3. The product with FLT3-ITD (1269 bp) was digested by EcoRV (1097 and 172 bp), but not the product of wild type (1191 bp) in lane 4, indicating that these mutations occurred on different alleles.
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Point mutations of the transcription factor AML1 are associated with leukemogenesis in acute myeloblastic leukemia (AML). Internal tandem duplications (ITDs) in the juxtamembrane domain and mutations in the second tyrosine kinase domain of the Fms-like tyrosine kinase 3 (FLT3) gene represent the most frequent genetic alterations in AML. However, su...
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Background
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Citations
... FLT3-ITD was the most common co-occurring mutation and significantly associated with RUNX1 mutation in paediatric AML, which may suggest cooperativity between these two mutations. An early report indicated a link between RUNX1 mutation and FLT3-ITD contributing to leukaemogenesis in AML M0, in which RUNX1 mutations predominated [51]. In comparison, FLT3-ITD frequently occurred in RUNX1-mutated adult AML, albeit evenly distributed and without correlation with RUNX1 mutation [15,39], supporting the notion of a cooperation between RUNX1 mutation and FLT3-ITD, which may be specific to paediatric AML [52]. ...
In acute myeloid leukaemia (AML) RUNX1 mutation is characterised by certain clinicopathological features with poor prognosis and adverse risk by the European LeukemiaNet recommendation. Though initially considered as provisional category, the recent World Health Organisation (WHO) classification of 2022 removed RUNX1-mutated AML from the unique entity. However, the significance of RUNX1 mutation in paediatric AML remains unclear. We retrospectively analysed a German cohort of 488 paediatric patients with de novo AML, enroled in the AMLR12 or AMLR17 registry of the AML-BFM Study Group (Essen, Germany). A total of 23 paediatric AML patients (4.7%) harboured RUNX1 mutations, 18 of which (78%) had RUNX1 mutation at initial diagnosis. RUNX1 mutations were associated with older age, male gender, number of coexisting alterations and presence of FLT3-ITD but mutually exclusive of KRAS, KIT and NPM1 mutation. RUNX1 mutations did not prognostically impact overall or event-free survival. Response rates did not differ between patients with and without RUNX1 mutations. This comprehensive study, comprising the largest analysis of RUNX1 mutation in a paediatric cohort to date, reveals distinct but not unique clinicopathologic features, with no prognostic significance of RUNX1-mutated paediatric AML. These results broaden the perspective on the relevance of RUNX1 alterations in leukaemogenesis in AML.
... An early report indicated a link between RUNX1 mutation and FLT3-ITD contributing to leukaemogenesis in AML M0, in which RUNX1 mutations predominated. 51 In comparison, FLT3-ITD frequently occurred in RUNX1mutated adult AML, albeit evenly distributed and without correlation with RUNX1 mutation, 15,39 supporting the notion of a cooperation between RUNX1 mutation and FLT3-ITD, which may be speci c to paediatric AML. 52 RUNX1 mutations were almost exclusive of alterations involved in other activatedsignalling pathways, namely NRAS, KRAS and KIT, which in contrast, were relatively common in the wtcohort. ...
In acute myeloid leukaemia (AML) RUNX1 mutation is characterized by certain clinicopathological features with poor prognosis and adverse risk by the European LeukemiaNet recommendation. Though initially considered as provisional category, the recent World Health Organization (WHO) classification of 2022 removed RUNX1 -mutated AML from the unique entity. However, the significance of RUNX1 mutation in paediatric AML remains unclear. We retrospectively analysed a German cohort of 488 paediatric patients with de novo AML, enrolled in the AMLR12 or AMLR17 registry of the AML-BFM Study Group (Essen, Germany). A total of 23 paediatric AML patients (4.7%) harboured RUNX1 mutations, 18 of which (3.7%) had RUNX1 mutation at initial diagnosis. RUNX1 mutations were associated with older age, male gender, number of coexisting alterations and presence of FLT3 -ITD but mutually exclusive of KRAS , KIT and NPM1 mutation. RUNX1 mutations did not prognostically impact overall- or event-free survival. Response rates did not differ between patients with and without RUNX1 mutations. This comprehensive study, comprising the largest analysis of RUNX1 mutation in a paediatric cohort to date, reveals distinct but not unique clinicopathologic features, with no prognostic significance of RUNX1 -mutated paediatric AML. These results broaden the perspective on the relevance of RUNX1 alterations in leukaemogenesis in AML.
... Leukemogenesis of MLs was found variable from one subtype to the other; therefore, the exact pathophysiology of MLs is a mystery. 1,2 Chromosomal translocations producing a new chimeric protein with novel functions play an important role in the pathogenesis of MLs, as well as activating mutations such as nucleophosmin gene mutation which offers a proliferative advantage to cells. [3][4][5] According to the WHO, MLs include acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic eosinophilic leukemia and the hypereosinophilic syndrome, biphenotypic leukemia and myeloid sarcomas (extramedullary MLs). ...
Video abstract Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use: https://youtu.be/wFhHrB-mNSM Background and objectives: Myeloid leukemias (MLs) are clonal stem cell disorders affecting myeloid lineage cells. Advances in cytogenetic and molecular studies partially disclosed the mystery about risk factors and pathophysiology of MLs. Regarding incidence, risk factors, response to treatment, and overall survival of patients, research showed differences among different countries. However, the Western registry data are the basis for the documented description of MLs in medical textbooks. This research aimed to study MLs in Middle Eastern health centers. Egypt has the highest population in the Middle East; furthermore, 96.6% of the population is native Egyptians; accordingly the study focused on Egypt. Patients and methods: Data of 468 patients with MLs were collected from hospital records at two big tertiary health centers. They were grouped into group 1 (chronic myeloid leukemia, CML) and group 2 (acute myeloid leukemia, AML); the latter was subgrouped into 2a (primary AML) and 2b (secondary AML). Results and conclusions: The median age of patients was 43 years; males predominate in group 2a and females in groups 1 and 2b. 37.2% of group 1 patients were treated with Gleevec. Hematopoietic stem cell transplantation was planned for only 5% of group 2 and 18% relapsed. Of groups 1 and 2 patients, 25% and 12%, respectively, stopped follow up, and 15% and 35% died. ORR and overall survival were 53%, 27% and 7%, 0.4% for groups 1 and 2, respectively. Conclusively, this study showed a young age of ML patients, with female predominance in CML, and poor outcome. This reflected racial, ethnic and risk factor differences in incidence of MLs.
... Leukemogenesis of MLs was found variable from one subtype to the other; therefore, the exact pathophysiology of MLs is a mystery. 1,2 Chromosomal translocations producing a new chimeric protein with novel functions play an important role in the pathogenesis of MLs, as well as activating mutations such as nucleophosmin gene mutation which offers a proliferative advantage to cells. [3][4][5] According to the WHO, MLs include acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic eosinophilic leukemia and the hypereosinophilic syndrome, biphenotypic leukemia and myeloid sarcomas (extramedullary MLs). ...
Background and objectives
Myeloid leukemias (MLs) are clonal stem cell disorders affecting myeloid lineage cells. Advances in cytogenetic and molecular studies partially disclosed the mystery about risk factors and pathophysiology of MLs. Regarding incidence, risk factors, response to treatment, and overall survival of patients, research showed differences among different countries. However, the Western registry data are the basis for the documented description of MLs in medical textbooks. This research aimed to study MLs in Middle Eastern health centers. Egypt has the highest population in the Middle East; furthermore, 96.6% of the population is native Egyptians; accordingly the study focused on Egypt.
Patients and methods
Data of 468 patients with MLs were collected from hospital records at two big tertiary health centers. They were grouped into group 1 (chronic myeloid leukemia, CML) and group 2 (acute myeloid leukemia, AML); the latter was subgrouped into 2a (primary AML) and 2b (secondary AML).
Results and conclusions
The median age of patients was 43 years; males predominate in group 2a and females in groups 1 and 2b. 37.2% of group 1 patients were treated with Gleevec. Hematopoietic stem cell transplantation was planned for only 5% of group 2 and 18% relapsed. Of groups 1 and 2 patients, 25% and 12%, respectively, stopped follow up, and 15% and 35% died. ORR and overall survival were 53%, 27% and 7%, 0.4% for groups 1 and 2, respectively. Conclusively, this study showed a young age of ML patients, with female predominance in CML, and poor outcome. This reflected racial, ethnic and risk factor differences in incidence of MLs.
... Co-occurring FLT3 and RUNX1 mutations have been previously described, with a hypothesis that loss of function RUNX1 mutations may predispose hematopoietic cells to overexpress activating mutations of FLT3 [24]. When examining the clinical implications of this hypothesis in patients with mutant RUNX1, our analysis interestingly found superior OS and EFS in mRUNX1 associated with FLT3 mutations. ...
(1) Runt-related transcription factor 1 (RUNX1) mutations in acute myeloid leukemia (AML) are often associated with worse prognosis. We assessed co-occurring mutations, response to therapy, and clinical outcomes in patients with and without mutant RUNX1 (mRUNX1); (2)We analyzed 328 AML patients, including 177 patients younger than 65 years who received intensive chemotherapy and 151 patients >65 years who received hypomethylating agents. RUNX1 and co-existing mutations were identified using next-generation sequencing; (3) RUNX1 mutations were identified in 5.1% of younger patients and 15.9% of older patients, and were significantly associated with increasing age (p = 0.01) as well as intermediate-risk cytogenetics including normal karyotype (p = 0.02) in the elderly cohort, and with lower lactate dehydrogenase (LDH; p = 0.02) and higher platelet count (p = 0.012) overall. Identified co-occurring mutations were primarily ASXL1 mutations in older patients and RAS mutations in younger patients; FLT3-ITD and IDH1/2 co-mutations were also frequent. Younger mRUNX1 AML patients treated with intensive chemotherapy experienced inferior treatment outcomes. In older patients with AML treated with hypomethylating agent (HMA) therapy, response and survival was independent of RUNX1 status. Older mRUNX1 patients with prior myelodysplastic syndrome or myeloproliferative neoplasms (MDS/MPN) had particularly dismal outcome. Future studies should focus on the prognostic implications of RUNX1 mutations relative to other co-occurring mutations, and the potential role of hypomethylating agents for this molecularly-defined group.
... 128,129,131 Furthermore, RUNX1 mutations are frequently observed together with FLT3-ITD, FLT3-TKD, and MLL-PTD. 126,128,131,132 In addition, mutations in other AML driver genes (ASXL1, CEBPA, DNMT3A, NRAS, KIT, IDH1, IDH2, WT1) are also observed in RUNX1-mutated AML samples. 128,129,131,132 Interestingly, RUNX1 and NPM1 mutations seem to be mutually exclusive. ...
... 126,128,131,132 In addition, mutations in other AML driver genes (ASXL1, CEBPA, DNMT3A, NRAS, KIT, IDH1, IDH2, WT1) are also observed in RUNX1-mutated AML samples. 128,129,131,132 Interestingly, RUNX1 and NPM1 mutations seem to be mutually exclusive. 128,129,131 These studies indicate that leukemogenesis is driven by mutations that provide a growth advantage to the hematopoietic progenitor cells with differentiation defects due to mutated RUNX1. ...
RUNX1 is a member of the core binding factor family of transcription factors and is indispensable for the establishment of definitive hematopoiesis in vertebrates. RUNX1 is one of the most frequently mutated genes in a variety of hematological malignancies. Germline mutations in RUNX1 cause familial platelet disorder with associated myeloid malignancies (FPDMM). Somatic mutations and chromosomal rearrangements involving RUNX1 are frequently observed in myelodysplastic syndrome (MDS) and leukemias of myeloid and lymphoid lineages, i.e. acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and chronic myelomonocytic leukemia (CMML). More recent studies suggest that the wildtype RUNX1 is required for growth and survival of certain types of leukemia cells. The purpose of this review is to discuss the current status of our understanding about the role of RUNX1 in hematological malignancies.
... Среди больных с промежуточным прогнозом заболевания мутация RUNX1 наиболее часто описана у пациентов с НК, трисомией хромосом 8 и 13 [90,91]. В некоторых исследованиях обнаружена высокая частота сочетания RUNX1 с мутациями FLT3 [88,92]. Однако некоторые исследователи не подтверждают данное наблюдение [89,91]. ...
Acute myeloid leukemia (AML) is a clonal malignancy characterized by ineffective hematopoiesis. Most AML patients present different cytogenetic and molecular defects associated with certain biologic and clinical features of the disease. Approximately 50-60 % of de novo AML and 80-95 % of secondary AML patients demonstrate chromosomal aberrations. Structural chromosomal aberrations are the most common cytogenetic abnormalities in about of 40 % of de novo AML patients. A relatively large group of intermediate risk patients with cytogenetically normal (CN) AML demonstrates a variety of outcomes. Current AML prognostic classifications include only some mutations with known prognostic value, namely NPM1, FLT3 and C/EBPa. Patients with NPM1 mutation, but without FLT3-ITD or C/EBPa mutations have a favorable prognosis, whereas patients with FLT3-ITD mutation have a poor prognosis. A new class of mutations affecting genes responsible for epigenetic mechanisms of genome regulations, namely for DNA methylation and histone modification, was found recently. Among them, mutations in genes DNMT3A, IDH1/2, TET2 and some others are the most well-studied mutations to date. A number of studies demonstrated an unfavorable prognostic effect of the DNMT3A mutation in AML. The prognostic significance of the IDH1/2 gene is still unclear. The prognosis is affected by a number of biological factors, including those associated with cytogenetic aberrations and other mutations, especially FLT3 and NPM1. The number of studies of genetic mutations in AML keeps growing. The data on genetic aberrations in AML obtained to date confirm their role in the onset and development of the disease.
... Among intermediate-risk AML, RUNX1 mutations are mostly associated with normal karyotype, with trisomy 8, and with trisomy 13 [90,91]. With regard to the correlation with other molecular makers, in some studies, a higher frequency of coincidence of FLT3 mutation and RUNX1 mutations was reported [88,92]. But data from Dicker et al. did not confirm that [89,91]. ...
Acute myeloid leukemia (AML) is a clonal disorder affecting pluripotent stem cells and is characterized by ineffective hematopoiesis. Most AML patients harbor cytogenetic and molecular defects that identify entities with peculiar biologic and clinical data and distinct therapeutic responses. Approximately 50%–60% of de novo AML and 80%–95% of secondary AML patients display chromosomal aberrations. Structural chromosomal rearrangements are the most common cytogenetic abnor‐ malities in de novo AML, with an incidence of 40%. Last years, large collaborative studies have demonstrated the importance of cytogenetic aberrations for the prognosis of AML patients. The large group of patients with cytogenetically normal (CN) AML refers to the intermediate risk category. It is known that this group of patients is very heterogene‐ ous with respect to prognosis. The recent large-scale sequencing of AML genomes is now providing opportunities for patient stratification and personalized approaches to treatments that are based on individual mutation profiles. Genes recurrently mutated in AML belong to distinct functional groups or pathways. A few recurring gene mutations with prognostic relevance in AML have been identified and have become incorporated into current prognostication models. For patients with CN AML, prognosis can be specified by mutational status of the genes NPM1, FLT3, and CEBPA. CN AML patients with NPM1 mutation, but no FLT3-ITD, or with CEBPA mutation, have a favorable prognosis. In contrast, CN AML patients with FLT3-ITD mutation have a poor prognosis.
... Point mutations in RUNX1 have been found in both de novo and secondary AML, following myelodysplastic syndrome or chemotherapy [114,116] and are capable of driving these diseases when introduced into the mouse germ line [117]. The majority of acquired RUNX1associated point mutations occurs in the RHD domain or the TAD domain and confers a very poor prognosis [112,116,118]. ...
The differentiation from multipotent hematopoietic stem cells (HSC) to mature and functional blood cells requires the finely tuned regulation of gene expression at each stage of development. Specific transcription factors play a key role in this process as they modulate the expression of their target genes in an exquisitely lineage-specific manner. A large number of important transcriptional regulators have been identified which establish and maintain specific gene expression patterns during hematopoietic development. Hematopoiesis is therefore a paradigm for investigating how transcription factors function in mammalian cells, thanks also to the evolution of genome-wide and the next-generation sequencing technologies. In this review, we focus on the current knowledge of the biological and functional properties of the hematopoietic master regulator RUNX1 (also known as AML1, CBFA2, PEBP2aB) transcription factor and its main downstream target PU.1. We will outline their relationship in determining the fate of the myeloid lineage during normal stem cell development and under conditions when hematopoietic development is subverted by leukemic transformation.
... It is generally held that RUNX1 mutation, a class II mutation, is involved as the initiating event to block the differentiation of hematopoietic cells, and the class I gene mutation synergistically provides growth advantages of these cells and leads to the development of AML [1,4,[26][27][28]. In the present study, three of 10 children with RUNX1 mutation had FLT3-ITD. ...
BackgroundRUNX1 mutation plays an important role in adult leukemic transformation. However, its contribution to the development of childhood leukemia remains unclear. In the present study, we analyzed point mutations of RUNX1 gene in children and adolescents with acute myeloid leukemia (AML) from Iraq and Jordan.ProcedureBone marrow and/or peripheral blood samples were collected from 178 patients of Arab Asian ethnicity (aged ≤17 years) newly diagnosed with AML: 145 samples from Iraq and 33 samples from Jordan. Direct DNA sequencing was performed on six genes including RUNX1 gene (exons 3–8).ResultsRUNX1 point mutations were identified in 10 (5.6%) of 178 patients. One patient possessed biallelic mutations of RUNX1 gene. C-terminal area was the predominant site of RUNX1 mutations (eight in C-terminal and two in N-terminal). Patients with RUNX1 mutations were significantly older than those with wild-type of the gene. Additionally, AML M0 subtype was more frequently found in patients with RUNX1 mutations. Both RUNX1 mutations and RAS mutations were identified in 4 of 10 children. Three patients with RUNX1 mutation had FLT3-ITD. On the other hand, 36 (21.4%) and 25 (14.9%) of 168 patients with wild-type of the gene had a RAS mutation and FLT3-ITD, respectively. Eight of 10 patients with RUNX1 mutations died of hematological relapse.Conclusion
The incidence of RUNX1 mutations in Arab Asian children and adolescents with AML was 5.6%. Further studies are required to clarify whether RAS mutations contribute to the development of pediatric AML associated with RUNX1 mutations. Pediatr Blood Cancer © 2014 Wiley Periodicals, Inc.
