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2.
Haematologica ; 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371409

RESUMO

Immunotherapeutic strategies targeting the rare leukemic stem cell compartment might provide salvage to the high relapse rates currently observed in acute myeloid leukemia. We applied gene expression profiling for comparison of leukemic blasts and leukemic stem cells with their normal counterparts. Here, we show that the T-cell receptor γ chain alternate reading frame protein (TARP) is overexpressed in de novo pediatric (n=13) and adult (n=17) acute myeloid leukemia sorted leukemic stem cells and blasts compared to hematopoietic stem cells and normal myeloblasts (15 healthy controls). Moreover, TARP expression was significantly associated with a fms-like tyrosine kinase receptor-3 internal tandem duplications in pediatric acute myeloid leukemia. TARP overexpression was confirmed in acute myeloid leukemia cell lines (n=9), and was found to be absent in B-cell acute lymphocytic leukemia (n=5) and chronic myeloid leukemia (n=1). Sequencing revealed that both a classical TARP transcript, as described in breast and prostate adenocarcinoma, and an acute myeloid leukemia-specific alternative TARP transcript, were present. Protein expression levels mostly matched transcript levels. TARP was shown to reside in the cytoplasmic compartment and showed sporadic endoplasmatic reticulum co-localization. TARP-T-cell receptor engineered cytotoxic T-cells in vitro killed acute myeloid leukemia cell lines and patient leukemic cells co-expressing TARP and HLA-A*0201. In conclusion, TARP qualifies as a relevant target for immunotherapeutic T-cell therapy in acute myeloid leukemia.

3.
Sci Rep ; 9(1): 10577, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332244

RESUMO

In cancer research, it remains challenging to functionally validate putative novel oncogenic drivers and to establish relevant preclinical models for evaluation of novel therapeutic strategies. Here, we describe an optimized and efficient pipeline for the generation of novel conditional overexpression mouse models in which putative oncogenes, along with an eGFP/Luciferase dual reporter, are expressed from the endogenous ROSA26 (R26) promoter. The efficiency of this approach was demonstrated by the generation and validation of novel R26 knock-in (KI) mice that allow conditional overexpression of Jarid2, Runx2, MN1 and a dominant negative allele of ETV6. As proof of concept, we confirm that MN1 overexpression in the hematopoietic lineage is sufficient to drive myeloid leukemia. In addition, we show that T-cell specific activation of MN1 in combination with loss of Pten increases tumour penetrance and stimulates the formation of Lyl1+ murine T-cell lymphoblastic leukemias or lymphomas (T-ALL/T-LBL). Finally, we demonstrate that these luciferase-positive murine AML and T-ALL/T-LBL cells are transplantable into immunocompromised mice allowing preclinical evaluation of novel anti-leukemic drugs in vivo.

4.
Pediatr Blood Cancer ; 66(5): e27605, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30623572

RESUMO

BACKGROUND: Children with acute myeloid leukemia (AML) have a 70% survival rate with treatment regimens containing high doses of cytarabine and anthracyclines and, in some, hematopoietic stem cell transplantation (allo-HSCT). PROCEDURE: In this multicenter Dutch-Belgian protocol (DB AML-01), 112 children with de novo AML were included. Treatment was stratified according to day 15 bone marrow response after the first induction course. Poor responders received a second course without delay while good responders awaited hematological recovery. Patients achieving CR after two induction courses continued with three consolidation courses without HSCT in CR1. RESULTS: The overall remission rate was 93.5%. After a median follow-up of 4.1 years, three-year event-free survival (EFS) was 52.6% (95% CI, 42.9%-61.3%), three-year cumulative incidence of relapse 39.7% (95% CI, 30.1%-49.0%), and three-year overall survival (OS) 74.0% (95% CI, 64.8%-81.2%). Significantly more events occurred in patients with high WBC at diagnosis or FLT3-ITD/NPM1-WT, whereas core binding factor (CBF) leukemia had a significantly better EFS. KMT2A rearrangements and age > 10 years negatively impacted OS. CONCLUSIONS: DB AML-01 response-guided therapy results in a favorable OS, particularly for children with CBF leukemia, children younger than 10 years or with initial WBC counts below 100 × 109 /L. Outcome of patients with FLT3-ITD/NPM1-WT remains poor and warrants alternative treatment strategies.

5.
JCI Insight ; 3(23)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30518699

RESUMO

In this study, the circulating miRNome from diagnostic neuroblastoma serum was assessed for identification of noninvasive biomarkers with potential in monitoring metastatic disease. After determining the circulating neuroblastoma miRNome, 743 miRNAs were screened in 2 independent cohorts of 131 and 54 patients. Evaluation of serum miRNA variance in a model testing for tumor stage, MYCN status, age at diagnosis, and overall survival revealed tumor stage as the most significant factor impacting miRNA abundance in neuroblastoma serum. Differential abundance analysis between patients with metastatic and localized disease revealed 9 miRNAs strongly associated with metastatic stage 4 disease in both patient cohorts. Increasing levels of these miRNAs were also observed in serum from xenografted mice bearing human neuroblastoma tumors. Moreover, murine serum miRNA levels were strongly associated with tumor volume. These findings were validated in longitudinal serum samples from metastatic neuroblastoma patients, where the 9 miRNAs were associated with disease burden and treatment response.

6.
Front Immunol ; 9: 2544, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30443258

RESUMO

Primary immunodeficiencies (PIDs) are a heterogeneous group of inherited disorders affecting one or multiple components of the innate and/or adaptive immune system. Currently, over 300 underlying genetic defects have been discovered. The most common clinical findings in patients with PIDs are infections, autoimmunity, and malignancies. Despite international efforts, the cancer risk associated with PIDs, given the heterogeneous character of this group of diseases, is difficult to estimate. The diverse underlying mechanisms of cancer in PID add another layer of complexity. Treatment of cancer within a context of PID is complicated by serious toxicities and long-term effects, including second malignancies. This review will focus on the little-known crossroad between PID and cancer genes and the value thereof for directing future research on our understanding of cancer in PID and for the identification of early cancer biomarkers in PID patients.

7.
Pediatr Blood Cancer ; : e27513, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30350915

RESUMO

Predisposition to cancer is only partly understood, and thus, the contribution of still undiscovered cancer predisposing variants necessitates further research. In search of such variants, we performed exome sequencing on the germline DNA of a family with two children affected by ganglioneuroma and neuroblastoma. Applying stringent selection criteria, we identified a potential deleterious, missense mutation in CLEC12B, coding for a lectin C-type receptor that is predicted to regulate immune function. Although further screening in a larger population and functional characterization is needed, we propose CLEC12B as a candidate cancer predisposition gene.

8.
Nature ; 562(7727): 373-379, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30209392

RESUMO

Mixed phenotype acute leukaemia (MPAL) is a high-risk subtype of leukaemia with myeloid and lymphoid features, limited genetic characterization, and a lack of consensus regarding appropriate therapy. Here we show that the two principal subtypes of MPAL, T/myeloid (T/M) and B/myeloid (B/M), are genetically distinct. Rearrangement of ZNF384 is common in B/M MPAL, and biallelic WT1 alterations are common in T/M MPAL, which shares genomic features with early T-cell precursor acute lymphoblastic leukaemia. We show that the intratumoral immunophenotypic heterogeneity characteristic of MPAL is independent of somatic genetic variation, that founding lesions arise in primitive haematopoietic progenitors, and that individual phenotypic subpopulations can reconstitute the immunophenotypic diversity in vivo. These findings indicate that the cell of origin and founding lesions, rather than an accumulation of distinct genomic alterations, prime tumour cells for lineage promiscuity. Moreover, these findings position MPAL in the spectrum of immature leukaemias and provide a genetically informed framework for future clinical trials of potential treatments for MPAL.

12.
Pediatr Blood Cancer ; 65(7): e27052, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29603574

RESUMO

BACKGROUND: The purpose of this study was to evaluate whether levels of neuroblastoma mRNAs in bone marrow and peripheral blood from stage M infants (≤12 months of age at diagnosis, MYCN amplified) and toddlers (between 12 and 18 months, any MYCN status) predict event-free survival (EFS). METHODS: Bone marrow aspirates and peripheral blood samples from 97 infants/toddlers enrolled in the European High-Risk Neuroblastoma trial were collected at diagnosis in PAXgene™ blood RNA tubes. Samples were analyzed by reverse transcription quantitative polymerase chain reaction according to standardized procedures. RESULTS: Bone marrow tyrosine hydroxylase (TH) or paired-like homeobox 2b (PHOX2B) levels in the highest tertile were associated with worse EFS; hazard ratios, adjusted for age and MYCN status, were 1.5 and 1.8 respectively. Expression of both TH and PHOX2B in the highest tertile predicted worse outcome (p = 0.015), and identified 20 (23%) infants/toddlers with 5-year EFS of 20% (95%CI: 4%-44%). Prognostic significance was maintained after adjusting for over-fitting bias (p = 0.038), age and MYCN status. In peripheral blood, PHOX2B levels in the highest tertile predicted a two-fold increased risk of an event (p = 0.032), and identified 23 (34%) infants/toddlers with 5-year EFS of 29% (95%CI: 12%-48%). Time-dependent receiver operating characteristic analysis confirmed the prognostic value of combined TH and PHOX2B in bone marrow and of PHOX2B in peripheral blood during the first year of follow-up. CONCLUSIONS: High levels of bone marrow TH and PHOX2B and of peripheral blood PHOX2B at diagnosis allow early identification of a group of high-risk infant and toddlers with neuroblastoma who may be candidates for alternative treatments. Integration with additional biomarkers, as well as validation in additional international trials is warranted.

13.
Cancer Res ; 78(6): 1549-1560, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29343523

RESUMO

Acute lymphoblastic leukemia (ALL) is the most common type of pediatric cancer, although about 4 of every 10 cases occur in adults. The enzyme drug l-asparaginase serves as a cornerstone of ALL therapy and exploits the asparagine dependency of ALL cells. In addition to hydrolyzing the amino acid l-asparagine, all FDA-approved l-asparaginases also have significant l-glutaminase coactivity. Since several reports suggest that l-glutamine depletion correlates with many of the side effects of these drugs, enzyme variants with reduced l-glutaminase coactivity might be clinically beneficial if their antileukemic activity would be preserved. Here we show that novel low l-glutaminase variants developed on the backbone of the FDA-approved Erwinia chrysanthemi l-asparaginase were highly efficacious against both T- and B-cell ALL, while displaying reduced acute toxicity features. These results support the development of a new generation of safer l-asparaginases without l-glutaminase activity for the treatment of human ALL.Significance: A new l-asparaginase-based therapy is less toxic compared with FDA-approved high l-glutaminase enzymes Cancer Res; 78(6); 1549-60. ©2018 AACR.

14.
Cytometry B Clin Cytom ; 94(4): 565-575, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28980766

RESUMO

BACKGROUND: Cancer-related gene expression data mostly originate from unfractionated bulk samples, leading to "expression averaging" of heterogeneous populations. Multicolor flow cytometry (FCM) may distinguish heterogeneous populations based on the phenotypic characterization of single-cells, but is not applicable for RNA targets. Here, we evaluated the PrimeFlow™ RNA assay, a novel FCM-based assay designed to measure gene expressions, in two cancer entities with high and low RNA target levels. METHODS: Neuroblastoma (NB) cell lines were studied for MYCN gene expression by PrimeFlow™ and compared with the gold standard, RT-qPCR. Dilution series of NB cells (0.10-11%) were prepared to evaluate performance in small cell populations. Diagnostic material of de novo acute myeloid leukemia (AML) patients was used to measure Wilms' tumor 1 (WT1) expression in bulk leukemic cells and rare subsets, e.g. leukemic stem cells (LSCs). FCM analysis was performed on a FACSCanto II (BD Biosciences) using Infinicyt™ (Cytognos® ) for data analysis. mRNA expression was reported by normalized mean fluorescence intensity (MFI) values and staining indices. RESULTS: MYCN mRNA quantified by PrimeFlow™ significantly correlated with RT-qPCR and remained detectable in small (0.1%) populations. Using PrimeFlowTM , WT1 levels were shown to be significantly higher in AML patient samples with WT1 overexpression, previously defined by RT-qPCR. Moreover, WT1 overexpression was distinguishable between heterogeneous cell populations and remained measurable in rare LSCs. CONCLUSION: PrimeFlow™ is a sensitive technique to investigate mRNA expressions, with high concordance to RT-qPCR. High (MYCN) and subtle (WT1) overexpressed mRNA targets can be quantified in heterogeneous and rare subpopulations e.g. LSCs. © 2017 International Clinical Cytometry Society.

17.
Front Immunol ; 9: 2912, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619276

RESUMO

Patients with inborn errors of immunity or DNA repair defects are at significant risk of developing malignancy and this complication of their underlying condition represents a substantial cause of morbidity and mortality. Whilst this risk is increasingly well-recognized, our understanding of the causative mechanisms remains incomplete. Diagnosing cancer is challenging in the presence of underlying co-morbidities and frequently other inflammatory and lymphoproliferative processes. We lack a structured approach to management despite recognizing the competing challenges of poor response to therapy and increased risk of toxicity. Finally, clinicians need guidance on how to screen for malignancy in many of these predisposing immunodeficiencies. In order to begin to address these challenges, we brought together representatives of European Immunology and Pediatric Haemato-Oncology to define the current state of our knowledge and identify priorities for clinical and research development. We propose key developmental priorities which our two communities will need to work together to address, collaborating with colleagues around the world.


Assuntos
Distúrbios no Reparo do DNA/complicações , Síndromes de Imunodeficiência/complicações , Neoplasias/diagnóstico , Neoplasias/terapia , Pesquisa , Alergia e Imunologia/tendências , Criança , Humanos , Comunicação Interdisciplinar , Oncologia/métodos , Oncologia/tendências , Neoplasias/complicações , Pediatria/métodos , Pediatria/tendências
18.
Clin Cancer Res ; 23(20): 6305-6314, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28710315

RESUMO

Purpose: Neuroblastoma (NB) is a heterogeneous disease characterized by distinct clinical features and by the presence of typical copy-number alterations (CNAs). Given the strong association of these CNA profiles with prognosis, analysis of the CNA profile at diagnosis is mandatory. Therefore, we tested whether the analysis of circulating cell-free DNA (cfDNA) present in plasma samples of patients with NB could offer a valuable alternative to primary tumor DNA for CNA profiling.Experimental Design: In 37 patients with NB, cfDNA analysis using shallow whole genome sequencing (sWGS) was compared with arrayCGH analysis of primary tumor tissue.Results: Comparison of CNA profiles on cfDNA showed highly concordant patterns, particularly in high-stage patients. Numerical chromosome imbalances as well as large and focal structural aberrations including MYCN and LIN28B amplification and ATRX deletion could be readily detected with sWGS using a low input of cfDNA.Conclusions: In conclusion, sWGS analysis on cfDNA offers a cost-effective, noninvasive, rapid, robust and sensitive alternative for tumor DNA copy-number profiling in most patients with NB. Clin Cancer Res; 23(20); 6305-14. ©2017 AACR.


Assuntos
Biomarcadores Tumorais , DNA Tumoral Circulante , Variações do Número de Cópias de DNA , Neuroblastoma/genética , Sequenciamento Completo do Genoma , Pré-Escolar , Hibridização Genômica Comparativa , Genes myc , Humanos , Lactente , Biópsia Líquida , Metástase Neoplásica , Estadiamento de Neoplasias , Neuroblastoma/diagnóstico
19.
J Mol Diagn ; 19(5): 659-672, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28736295

RESUMO

Recurrent and clonal genetic alterations are characteristic of different subtypes of T- and B-cell lymphoblastic leukemia (ALL), and several subtypes are strong independent predictors of clinical outcome. A next-generation sequencing-based multiplex ligation-dependent probe amplification variant (digitalMLPA) has been developed enabling simultaneous detection of copy number alterations (CNAs) of up to 1000 target sequences. This novel digitalMLPA assay was designed and optimized to detect CNAs of 56 key target genes and regions in ALL. A set of digital karyotyping probes has been included for the detection of gross ploidy changes, to determine the extent of CNAs, while also serving as reference probes for data normalization. Sixty-seven ALL patient samples (including B- and T-cell ALL), previously characterized for genetic aberrations by standard MLPA, array comparative genomic hybridization, and/or single-nucleotide polymorphism array, were analyzed single blinded using digitalMLPA. The digitalMLPA assay reliably identified whole chromosome losses and gains (including high hyperdiploidy), whole gene deletions or gains, intrachromosomal amplification of chromosome 21, fusion genes, and intragenic deletions, which were confirmed by other methods. Furthermore, subclonal alterations were reliably detected if present in at least 20% to 30% of neoplastic cells. The diagnostic sensitivity of the digitalMLPA assay was 98.9%, and the specificity was 97.8%. These results merit further consideration of digitalMLPA as a valuable alternative for genetic work-up of newly diagnosed ALL patients.


Assuntos
Variações do Número de Cópias de DNA , Tipagem de Sequências Multilocus/métodos , Técnicas de Amplificação de Ácido Nucleico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Biomarcadores Tumorais , Linhagem Celular Tumoral , Sondas de DNA , Feminino , Variação Genética , Humanos , Masculino , Tipagem de Sequências Multilocus/normas , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Controle de Qualidade , Reprodutibilidade dos Testes
20.
Curr Opin Hematol ; 24(4): 353-358, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28441150

RESUMO

PURPOSE OF REVIEW: Over the last years, long non-coding RNAs (lncRNAs) have emerged as putative regulators of malignant hematopoietic development. Here, we review recent literature on the involvement of lncRNAs in leukemia, including their role in driving or sustaining disease and their potential impact on diagnosis, classification, and prognosis. RECENT FINDINGS: Leukemogenesis is a complex process resulting from the accumulation of multiple genetic alterations. Over the last years, advances in high-throughput sequencing and transcriptome profiling have enabled the identification of lncRNAs involved in leukemia development. lncRNAs are able to distinguish different subtypes of human leukemia and several reports have identified specific patterns of lncRNA expression associated with clinical patient characteristics. Although functional studies on the actual role of these lncRNAs during transformation remain scarce, emerging evidence suggests that complex interactions between coding and non-coding transcript are truly involved in leukemia development. SUMMARY: Introduction of lncRNAs as an additional layer of complexity in human leukemia might provide new molecular genetic insights in the biology of this disease and could create unique opportunities for the identification of novel drug targets and diagnostic or prognostic biomarkers.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia/genética , RNA Longo não Codificante/genética , Biomarcadores , Transformação Celular Neoplásica/genética , Montagem e Desmontagem da Cromatina/genética , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Leucemia/diagnóstico , Leucemia/metabolismo , Leucemia/mortalidade , Prognóstico , Transdução de Sinais
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