Expression of meningioma 1 (MN1) has been proposed to be a negative prognostic molecular marker in adult AML with normal cytogenetics, however its role in pediatric leukemia is unknown. We found elevated MN1 expression in 53 of 88 pediatric leukemia cases: significant amounts of MN1 were found in immature B-cell ALL and most cases of infant leukemia but no MN1 expression was detected in T-cell acute lymphoblastic leukemia (T-ALL). Interestingly 17 of 19 cases harboring MLL-X fusions showed also elevated MN1 expression. Lentiviral siRNA mediated MN1 knock-down resulted in cell cycle arrest and impaired clonogenic growth of 3 MLL-X-positive human leukemia cell lines overexpressing MN1 (THP-1, RS4;11, MOLM13). In a mouse MLL/ENL-induced leukemia MN1 overexpression resulted from retroviral provirus insertion. Strikingly co-expression of MN1 with MLL/ENL resulted in significantly reduced latency for induction of an AML phenotype in mice suggesting functional cooperation. MN1 overexpression in MLL/ENL-carrying cells resulted in expansion of the L-GMP population and facilitated disease induction in secondary recipients. Gene expression profiling allowed to define a number of potential MN1 hematopoietic targets. Up-regulation of CD34, FLT3, HLF, or DLK1 was validated in bone marrow transiently overexpressing MN1, in MN1-induced mouse leukemias, as well as in some cases of pediatric leukemias overexpressing MN1. Taken together, our work suggests that MN1 overexpression is essential for growth of leukemic cells, and that MN1 can act as a cooperating oncogene with MLL-X fusion genes most probably through modification of a distinct gene expression program that leads to expansion of a leukemia initiating cell population.
Functional characterization of high levels of meningioma 1 as collaborating oncogene in acute leukemia.
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View SamplesAcute lymphoblastic pediatric leukemia specimens without known genetic hallmarks are examined for hidden genomic aberrancies and related gene expression profiles
Integration of genomic and gene expression data of childhood ALL without known aberrations identifies subgroups with specific genetic hallmarks.
No sample metadata fields
View SamplesDespite improved therapy, approximately one-fifth of children with acute T-lymphoblastic leukemia (T-ALL) succumb to the disease, suggesting unrecognized biologic heterogeneity that may contribute to drug resistance. We studied leukemic cells, collected at diagnosis, to identify features that could define this high-risk subgroup. A total of 139 patients with T-ALL were treated consecutively from 1992 to 2006 at this institution. Their leukemic cells were examined with multiparameter flow cytometry, single nucleotide polymorphism arrays and other methods of genomic analysis. Survival rates and probabilities of treatment failure were calculated for subgroups considered to have biologically distinct forms of T-ALL.
Early T-cell precursor leukaemia: a subtype of very high-risk acute lymphoblastic leukaemia.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
High expression of miR-125b-2 and SNORD116 noncoding RNA clusters characterize ERG-related B cell precursor acute lymphoblastic leukemia.
Specimen part, Disease, Disease stage
View SamplesERG-related B cell precursor acute lymphoblastic leukemia (BCP ALL) is a recently described childhood ALL subtype characterized by aberrant ERG protein expression and highly recurrent ERG intragenic deletions. Several studies reported a remarkably favourable outcome for ERG-related BCP-ALL despite a high incidence of apparently inauspicious IKZF1 aberrations. In this study we investigated by integrative genomic analysis the main features of the ERG-related group in a cohort of B-others BCP ALL patients enrolled in the AIEOP ALL 2000 therapeutic protocol. We report a specific microRNA and snoRNA signature that characterizes ERG-related patients with up-regulation of the miR-125b-2 cluster on chromosome 21 and several snoRNAs in the Prader-Willi locus at 15q11.2, including the orphan SNORD116 cluster. Given the current lack of parameters for a comprehensive classification we suggest toexploit the noncoding RNAs signature for differential diagnosis of ERG-related patients.
High expression of miR-125b-2 and SNORD116 noncoding RNA clusters characterize ERG-related B cell precursor acute lymphoblastic leukemia.
Specimen part, Disease, Disease stage
View SamplesGEP class prediction in association with CI-FISH (42 candidate genes) and patient MRD stratification
Linking genomic lesions with minimal residual disease improves prognostic stratification in children with T-cell acute lymphoblastic leukaemia.
Specimen part, Disease, Disease stage
View SamplesWe studied the in vitro and in vivo efficacy of the HDAC inhibitor Givinostat/ITF2357 in BCP-ALL with CRLF2 rearrangements. We used BCP-ALL CRLF2- rearranged MHH-CALL4 and MUTZ5 cell lines as well as blasts from CRLF2 rearranged BCP-ALL patients and patients derived xenograft samples. We conclude that Givinostat may represent a novel and effective tool, in combination with current chemotherapy, to treat this subsets of ALL with poor prognosis and chemotherapy-related toxicity.
The histone deacetylase inhibitor givinostat (ITF2357) exhibits potent anti-tumor activity against CRLF2-rearranged BCP-ALL.
Specimen part, Treatment
View SamplesWe examined if the minimal residual disease (MRD) and the Allelic Ratio (AR) of FLT3 internal tandem duplication (ITD) mutated patients may be prognostic factors. We correlated these parameters both with event free survival (EFS), with incidence of relapse and with gene expression profile (GEP). GEP showed that patients with high-ITD-AR or persistent MRD had different expression profiles. Results indicated that the ITD-AR levels and the MRD after I induction course are associated with transcriptional oncogenic profiles, which highlight differences in epigenetic control that may explain the variability in outcome among FLT3-ITD patients
Characterization of children with FLT3-ITD acute myeloid leukemia: a report from the AIEOP AML-2002 study group.
Specimen part, Disease
View SamplesThe purpose of this experiment was to assess the genes upregulated when pDCs were stimulated with TLR7 agonist imiquimod and TLR9 agonist CpG C. Overall design: pDCs were isolated from six healthy donors by FACS sorting, and were stimulated with CpG and imiquimod for 18 hours, after which RNA was extracted for next generation sequencing on the Illumina HiSeq platform. Unstimulated samples were included as controls.
A cytotoxic anti-IL-3Rα antibody targets key cells and cytokines implicated in systemic lupus erythematosus.
No sample metadata fields
View SamplesWe investigated the anti-leukemic effects of the Bromodomain and Extra Terminal inhibitor I-BET151 on primary MLL-AF4 patient samples, using a xenotransplantation mouse model of MLL+ infant ALL in vivo. We reported that I-BET151 treatment impairs the engraftment and the disease burden of primary MLL+ infant ALL samples transplanted into immunedeficient mice. I-BET151 is able to arrest the growth of leukemic cells by blocking cell division and rapidly inducing apoptosis, through the deregulation of crucial target genes of the BRD4 and HOXA9/HOXA7 network. Moreover I-BET151 sensitizes glucocorticoid-resistant MLL+ cells to Prednisolone. Finally we observed that I-BET151 treatment is even more efficient when used in combination with HDAC inhibitor.
Antileukemic Efficacy of BET Inhibitor in a Preclinical Mouse Model of MLL-AF4<sup>+</sup> Infant ALL.
Treatment, Subject
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