Similar Datasets
Project description:UBTF tandem duplications (TD) have recently emerged as a subtype-defining alteration in pediatric acute myeloid leukemia (pAML), which is characterized by HOXB gene dysregulation and a poor response to conventional chemotherapy. Here, we use protein-protein interaction studies to show that UBTF-TD maintains interactions with components of the RNA pol I complex, while also engaging with a network of unique protein interactors specific to UBTF-TD, like KMT2A. These data suggest that UBTF- TD both preserves canonical UBTF functions and demonstrates gain of function activities. Furthermore, we show that UBTF-TD and KMT2A co-localize to key genomic targets dysregulated in UBTF-TD myeloid malignancies, like HOXB gene clusters and MEIS1. Using a protein degradation system, we show that stemness, proliferation, and the HOXB molecular signature are dependent on sustained UBTF-TD localization to chromatin. Finally, we show UBTF-TD leukemias are sensitive to menin inhibition—providing a viable therapeutic strategy for children with this high-risk AML subtype.
2024-02-12 | GSE229664 | GEO
Project description:UBTF tandem duplications (TD) have recently emerged as a subtype-defining alteration in pediatric acute myeloid leukemia (pAML), which is characterized by HOXB gene dysregulation and a poor response to conventional chemotherapy. Here, we use protein-protein interaction studies to show that UBTF-TD maintains interactions with components of the RNA pol I complex, while also engaging with a network of unique protein interactors specific to UBTF-TD, like KMT2A. These data suggest that UBTF- TD both preserves canonical UBTF functions and demonstrates gain of function activities. Furthermore, we show that UBTF-TD and KMT2A co-localize to key genomic targets dysregulated in UBTF-TD myeloid malignancies, like HOXB gene clusters and MEIS1. Using a protein degradation system, we show that stemness, proliferation, and the HOXB molecular signature are dependent on sustained UBTF-TD localization to chromatin. Finally, we show UBTF-TD leukemias are sensitive to menin inhibition—providing a viable therapeutic strategy for children with this high-risk AML subtype.
2024-02-12 | GSE229663 | GEO
Project description:To investigate the effect of Menin inhibitor on UBTF-TD harboring AML. We characterized UBTF-TD interaction with KMT2A and Menin in different leukemia models including KMT2A-r, transduced and normal cbCD34+ cells as well as in primary AML cells with UBTF-TD mutation. We also analized gene expression pattern upon treatment with Menin inhibitor.
2023-12-01 | GSE233810 | GEO
Project description:Genomic profiling of relapsed pediatric AML demonstrated an increase in KMT2A and NUP98 rearrangements when compared to de novo pediatric AML, as well as an increase in WT1 mutations. Notably, we identified recurrent (9% of relapse cohort) exon 13 duplications in UBTF in pediatric AML cases that previously lacked known driver alterations. These UBTF-tandem duplication (TD) pediatric AMLs occur in approximately 4% of all pediatric AMLs and are less common in adult AMLs, are associated with normal karyotype or trisomy 8 cytogenetic abnormalities, co-occur with WT1 and FLT3-ITD, have an expression profile similar to NUP98-NSD1 and NPM1 mutant AMLs and are independently associated with poor outcome.
| EGAS00001005760 | EGA
Project description:Incidence, molecular presentation and outcome of acute myeloid leukaemia (AML) are influenced by sex, but little attention has been directed at untangling sex-related molecular and phenotypic differences between female and male patients. While increased incidence and poor risk are generally associated with a male phenotype, the poor prognostic FLT3 internal tandem duplication (FLT3-ITD) mutation and co-mutations with NPM1 and DNMT3A are overrepresented in female AML. Here, we have investigated the relationship between sex and FLT3-ITD mutation status by comparing clinical data, mutational profiles, gene expression and ex vivo drug sensitivity in four cohorts: Beat AML, LAML-TCGA and two independent HOVON/SAKK cohorts, comprising 1755 AML patients in total. We found prevalent sex-associated molecular differences. Co-occurrence of FLT3-ITD, NPM1 and DNMT3A mutations was overrepresented in females, while males with FLT3-ITDs were characterized by additional mutations in RNA splicing and epigenetic modifier genes. We observed diverging expression of multiple leukaemia-associated genes as well as discrepant ex vivo drug responses, suggestive of discrete functional properties. Importantly, significant prognostication was observed only in female FLT3-ITD-mutated AML. Thus, we suggest optimization of FLT3-ITD mutation status as a clinical tool in a sex-adjusted manner and hypothesize that prognostication, prediction and development of therapeutic strategies in AML could be improved by including sex-specific considerations.
| S-EPMC8410575 | biostudies-literature
Project description:FLT3 internal tandem duplications (FLT3/ITDs) in the juxtamembrane domain are found in approximately 25% of acute myeloid leukemia (AML) patients, ranging in size from 3 to hundreds of nucleotides. We examined whether the sizes of FLT3/ITDs were associated with clinical outcomes in 151 AML patients enrolled in Southwest Oncology Group studies: S9333 and S9500. FLT3/ITDs were identified in 32% of patients (median ITD size = 39 nucleotides; range, 15-153 nucleotides). The CR rates were 35%, 67%, and 52% for patients with large (>or= 40), small (< 40), and no ITDs, respectively (P = .19). Increasing ITD size was associated with decreasing OS (estimated 5-year OS: large = 13%, small = 26%, and no ITD = 21%, P = .072) and RFS (estimated 5-year RFS: large = 13%, small = 27%, and no ITD = 34%, P = .017). These studies suggest that ITD size may have prognostic significance.
| S-EPMC1895777 | biostudies-literature
Project description:Partial tandem duplication of MLL (MLL-PTD) characterizes acute myeloid leukemia (AML) patients often with a poor prognosis. To understand the order of occurrence of MLL-PTD in relation to other major AML mutations and to identify novel mutations that may be present in this unique AML molecular subtype, exome and targeted sequencing was performed on 85 MLL-PTD AML samples using HiSeq-2000. Genes involved in the cohesin complex (STAG2), a splicing factor (U2AF1) and a poorly studied gene, MGA were recurrently mutated, whereas NPM1, one of the most frequently mutated AML gene, was not mutated in MLL-PTD patients. Interestingly, clonality analysis suggests that IDH2/1, DNMT3A, U2AF1 and TET2 mutations are clonal and occur early, and MLL-PTD likely arises after these initial mutations. Conversely, proliferative mutations (FLT3, RAS), typically appear later, are largely subclonal and tend to be unstable. This study provides important insights for understanding the relative importance of different mutations for defining a targeted therapeutic strategy for MLL-PTD AML patients.
| S-EPMC5214979 | biostudies-literature
Project description:Pediatric acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) exhibit favorable survival rates. However, for AML and ALL patients carrying KMT2A gene translocations clinical outcome remains unsatisfactory. Key players in KMT2A-fusion-driven leukemogenesis include menin and DOT1L. Recently, menin inhibitors like revumenib have garnered attention for their potential therapeutic efficacy in treating KMT2A-rearranged acute leukemias. However, resistance to menin inhibition poses challenges, and identifying which patients would benefit from revumenib treatment is crucial. Here, we investigated the in vitro response to revumenib in KMT2A-rearranged ALL and AML. While ALL samples show rapid, dose-dependent induction of leukemic cell death, AML responses are much slower and promote myeloid differentiation. Furthermore, we reveal that acquired resistance to revumenib in KMT2A-rearranged ALL cells can occur either through the acquisition of MEN1 mutations or independently of mutations in MEN1. Finally, we demonstrate significant synergy between revumenib and the DOT1L inhibitor pinometostat in KMT2A-rearranged ALL, suggesting that such drug combinations represent a potent therapeutic strategy for these patients. Collectively, our findings underscore the complexity of resistance mechanisms and advocate for precise patient stratification to optimize the use of menin inhibitors in KMT2A-rearranged acute leukemia.
| S-EPMC11173273 | biostudies-literature
Project description:Epigenetic mechanisms affecting chromatin structure contribute to regulate gene expression and assure the inheritance of information, which are essential for the proper expression of key regulatory genes in healthy cells, tissues and organs. In the medical field, an increasing body of evidence indicates that altered gene expression or de-regulated gene function lead to disease. Cancer cells also suffer a profound change in the genomic methylation patterns and chromatin status. Aberrant DNA methylation patterns, changes in chromatin structure and in gene expression are common in all kind of tumor types. However, studies on leukemias have provided paradigmatic examples for the functional implications of the epigenetic alterations in cancer development and progression as well as their relevance for therapeutical targeting.
| S-EPMC2764862 | biostudies-literature
Project description:We evaluated standard-of-care (SOC) treatment with or without midostaurin to prevent relapse following allogeneic hematopoietic stem cell transplant (alloHSCT) in patients with acute myeloid leukemia (AML) harboring internal tandem duplication (ITD) in FLT3. Adults (aged 18-70 years) who received alloHSCT in first complete remission, had achieved hematologic recovery, and were transfusion independent were randomized to receive SOC with or without midostaurin (50 mg twice daily) continuously in twelve 4-week cycles. The primary endpoint was relapse-free survival (RFS) 18 months post-alloHSCT. Sixty patients were randomized (30/arm); 30 completed all 12 cycles (midostaurin + SOC, n = 16; SOC, n = 14). The estimated 18-month RFS (95% CI) was 89% (69-96%) in the midostaurin arm and 76% (54-88%) in the SOC arm (hazard ratio, 0.46 [95% CI, 0.12-1.86]; P = 0.27); estimated relapse rates were 11% and 24%, respectively. Inhibition of FLT3 phosphorylation to <70% of baseline (achieved by 50% of midostaurin-treated patients) was associated with improved RFS. The most common serious adverse events were diarrhea, nausea, and vomiting. Rates of graft-vs-host disease were similar between both arms (midostaurin + SOC, 70%; SOC, 73%). The addition of midostaurin maintenance therapy following alloHSCT may provide clinical benefit in some patients with FLT3-ITD AML. (ClinicalTrials.gov identifier: NCT01883362).
| S-EPMC8113057 | biostudies-literature