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1.
JAMA Oncol ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944221

RESUMO

Importance: A randomized clinical trial is needed to determine whether the second-generation Abl-tyrosine kinase inhibitor dasatinib is more effective than the first-generation inhibitor imatinib mesylate for childhood Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL). Objective: To determine whether dasatinib given at a daily dosage of 80 mg/m2 is more effective than imatinib mesylate at a daily dosage of 300 mg/m2 to improve event-free survival of children with Philadelphia chromosome-positive ALL in the context of intensive chemotherapy without prophylactic cranial irradiation. Design, Setting, and Participants: This open-label, phase 3 randomized clinical trial was conducted at 20 hospitals in China. Enrollment occurred from January 1, 2015, through September 18, 2018, and randomization was stopped on October 4, 2018, when the early stopping criterion of the trial was met. Patients aged 0 to 18 years were recruited. Of the 225 patients with the diagnosis, 35 declined participation and 1 died before treatment, leaving 189 patients available for analysis. Data were analyzed from January 1 through August 4, 2019. Interventions: Patients were randomized to receive daily dasatinib (n = 92) or imatinib (n = 97) continuously for the entire duration of ALL therapy from the time of diagnosis made during remission induction to the end of continuation therapy. Main Outcomes and Measures: The primary outcome was event-free survival, analyzed based on intention to treat. The secondary outcomes were relapse, death due to toxic effects, and overall survival. Results: Among the 189 participants (136 male [72.0%]; median age, 7.8 [interquartile range (IQR), 5.2-11.3] years) and a median follow-up of 26.4 (IQR, 16.3-34.1) months, the 4-year event-free survival and overall survival rates were 71.0% (95% CI, 56.2%-89.6%) and 88.4% (95% CI, 81.3%-96.1%), respectively, in the dasatinib group and 48.9% (95% CI, 32.0%-74.5%; P = .005, log-rank test) and 69.2% (95% CI, 55.6%-86.2%; P = .04, log-rank test), respectively, in the imatinib group. The 4-year cumulative risk of any relapse was 19.8% (95% CI, 4.2%-35.4%) in the dasatinib group and 34.4% (95% CI, 15.6%-53.2%) in the imatinib group (P = .01, Gray test), whereas the 4-year cumulative risk of an isolated central nervous system relapse was 2.7% (95% CI, 0.0%-8.1%) in the dasatinib group and 8.4% (95% CI, 1.2%-15.6%) in the imatinib group (P = .06, Gray test). There were no significant differences in the frequency of severe toxic effects between the 2 treatment groups. Conclusions and Relevance: Intensive chemotherapy including dasatinib at a dosage of 80 mg/m2 per day yielded superior results in the treatment of Philadelphia chromosome-positive ALL compared with imatinib mesylate at a dosage of 300 mg/m2 per day and provided excellent control of central nervous system leukemia without the use of prophylactic cranial irradiation. Trial Registration: Chinese Clinical Trial Registry: ChiCTR-IPR-14005706.

2.
Blood ; 135(1): 41-55, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31697823

RESUMO

To study the mechanisms of relapse in acute lymphoblastic leukemia (ALL), we performed whole-genome sequencing of 103 diagnosis-relapse-germline trios and ultra-deep sequencing of 208 serial samples in 16 patients. Relapse-specific somatic alterations were enriched in 12 genes (NR3C1, NR3C2, TP53, NT5C2, FPGS, CREBBP, MSH2, MSH6, PMS2, WHSC1, PRPS1, and PRPS2) involved in drug response. Their prevalence was 17% in very early relapse (<9 months from diagnosis), 65% in early relapse (9-36 months), and 32% in late relapse (>36 months) groups. Convergent evolution, in which multiple subclones harbor mutations in the same drug resistance gene, was observed in 6 relapses and confirmed by single-cell sequencing in 1 case. Mathematical modeling and mutational signature analysis indicated that early relapse resistance acquisition was frequently a 2-step process in which a persistent clone survived initial therapy and later acquired bona fide resistance mutations during therapy. In contrast, very early relapses arose from preexisting resistant clone(s). Two novel relapse-specific mutational signatures, one of which was caused by thiopurine treatment based on in vitro drug exposure experiments, were identified in early and late relapses but were absent from 2540 pan-cancer diagnosis samples and 129 non-ALL relapses. The novel signatures were detected in 27% of relapsed ALLs and were responsible for 46% of acquired resistance mutations in NT5C2, PRPS1, NR3C1, and TP53. These results suggest that chemotherapy-induced drug resistance mutations facilitate a subset of pediatric ALL relapses.

3.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(11): 1073-1078, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31753087

RESUMO

OBJECTIVE: To study the clinical effect of the SCMC APL-2010 regimen in the treatment of acute promyelocytic leukemia (APL) in children. METHODS: A retrospective analysis was performed for the clinical data of 44 children with APL who received treatment with the SCMC APL-2010 regimen between April 2010 and July 2016. The Kaplan-Meier survival analysis was used to evaluate event-free survival (EFS) rate and overall survival (OS) rate. RESULTS: Of the 44 children with APL, 42 (95%) achieved a complete remission (CR) after one course of treatment and 1 achieved CR after two courses of treatment, with an overall CR rate of 98%. The 9-year EFS and OS rates were 96%±3% and 97.7%±2.2% respectively. As for adverse events, 41 (93%) had infection, 29 (66%) had granulocyte reduction, 12 (27%, 1 died) had differentiation syndrome, 16 (36%) had liver dysfunction, 12 (27%) had adverse gastrointestinal reactions, and 7 (16%) had QT prolongation, 1 (2%) had orchitis, and no secondary neoplasm was observed. CONCLUSIONS: Children with APL receiving the SCMC APL-2010 regimen have a good prognosis and can achieve a long-term survival, while treatment-related infection is commonly seen.


Assuntos
Leucemia Promielocítica Aguda , Protocolos de Quimioterapia Combinada Antineoplásica , Criança , Intervalo Livre de Doença , Humanos , Masculino , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento , Tretinoína
4.
Haematologica ; 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467124

RESUMO

Hematopoiesis is a finely regulated process in vertebrates under both homeostatic and stress conditions. By whole exome sequencing we have studied the genomics of acute lymphoid leukemia patients who needed multiple red blood cell transfusions after intensive chemotherapies. ARHGEF12, encoding a RhoA guanine nucleotide exchange factor, was found associated with chemotherapy-induced anemia by genome-wide association study analyses. A single nucleotide polymorphism (SNP) of ARHGEF12 located in an intron predicted to be a GATA1 binding site, rs10892563, is significantly associated with patients who need red blood cell transfusion (P=3.469E-03, odds ratio 5.864). A luciferase reporter assay revealed that this SNP impairs GATA1 mediated trans-regulation of ARHGEF12, and quantitative PCR studies confirmed that the homozygotes status is associated with ~61% reduction of ARHGEF12 expression (P=0.0088). Consequently, erythropoiesis was affected at the pro-erythroblast phase in the patients. A role of ARHGEF12 and its homologs in erythroid differentiation was confirmed in human K562 cells, mouse 32D cells and primary murine bone marrow cells. We further demonstrated in zebrafish by morpholino-mediated knockdown and CRISPR/Cas9-mediated knockout of arhgef12 that its reduction resulted in erythropoiesis defects. The p38 kinase pathway was affected by the ARHGEF12-RhoA signaling in K562 cells, and consistently, the arhgef12-rhoA-p38 pathway was also shown to be important for erythroid differentiation in zebrafish as active rhoA or p38 readily rescued the impaired erythropoiesis caused by arhgef12 knocking down. Finally, ARHGEF12 mediated p38 activity also appeared to be involved in phenotypes of patients of the rs10892563 homozygous genotype. Our findings present a novel SNP of ARHGEF12 that may involve ARHGEF12-RhoA-p38 signaling in erythroid regeneration in acute lymphoblastic leukemia patients after chemotherapy.

5.
Nanoscale ; 11(23): 11114-11120, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31166339

RESUMO

Inspired by biological neural systems, neuromorphic devices may lead to new computing paradigms for exploring cognition, learning and limits of parallel computation. Synapses form the basis of neuromorphic computing and have attracted significant research interest in recent years. Herein, a three-terminal transistor based on a transition metal sulfide and zinc oxide heterojunction is proposed for emulating biological synapses. The transistor exhibits an ON/OFF ratio (104) and significant rectifying behavior with forward-to-reverse bias current ratios of 104. The device demonstrates the essential synaptic behaviors, such as excitatory postsynaptic current, modulation of synaptic weight and paired-pulse facilitation. Furthermore, we show that the hysteretic effect of the transfer curves and the post-synapse current triggered by the presynaptic pulses can be modulated by illumination, and the current under illumination conditions is about 10 times greater than that in the dark. These synapses combine photonic with electric neuromorphic functions, thus showing the application prospects of the optoelectronic interfaces for integrated photonic circuits based on mixed-mode electro-optical operation. Hence, this work offers a new landscape for 2D-material electronics and encourages future research on neuro-electronics.

6.
Leukemia ; 33(10): 2365-2378, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30940905

RESUMO

Bone marrow (BM) niche responds to chemotherapy-induced cytokines secreted from acute lymphoblastic leukemia (ALL) cells and protects the residual cells from chemotherapeutics in vivo. However, the underlying molecular mechanisms for the induction of cytokines by chemotherapy remain unknown. Here, we found that chemotherapeutic drugs (e.g., Ara-C, DNR, 6-MP) induced the expression of niche-protecting cytokines (GDF15, CCL3 and CCL4) in both ALL cell lines and primary cells in vitro. The ATM and NF-κB pathways were activated after chemotherapy treatment, and the pharmacological or genetic inhibition of these pathways significantly reversed the cytokine upregulation. Besides, chemotherapy-induced NF-κB activation was dependent on ATM-TRAF6 signaling, and NF-κB transcription factor p65 directly regulated the cytokines expression. Furthermore, we found that both pharmacological and genetic perturbation of ATM and p65 significantly decreased the residual ALL cells after Ara-C treatment in ALL xenograft mouse models. Together, these results demonstrated that ATM-dependent NF-κB activation mediated the cytokines induction by chemotherapy and ALL resistance to chemotherapeutics. Inhibition of ATM-dependent NF-κB pathway can sensitize ALL to chemotherapeutics, providing a new strategy to eradicate residual chemo-resistant ALL cells.

7.
Genome Biol ; 20(1): 50, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30867008

RESUMO

BACKGROUND: Sequencing errors are key confounding factors for detecting low-frequency genetic variants that are important for cancer molecular diagnosis, treatment, and surveillance using deep next-generation sequencing (NGS). However, there is a lack of comprehensive understanding of errors introduced at various steps of a conventional NGS workflow, such as sample handling, library preparation, PCR enrichment, and sequencing. In this study, we use current NGS technology to systematically investigate these questions. RESULTS: By evaluating read-specific error distributions, we discover that the substitution error rate can be computationally suppressed to 10-5 to 10-4, which is 10- to 100-fold lower than generally considered achievable (10-3) in the current literature. We then quantify substitution errors attributable to sample handling, library preparation, enrichment PCR, and sequencing by using multiple deep sequencing datasets. We find that error rates differ by nucleotide substitution types, ranging from 10-5 for A>C/T>G, C>A/G>T, and C>G/G>C changes to 10-4 for A>G/T>C changes. Furthermore, C>T/G>A errors exhibit strong sequence context dependency, sample-specific effects dominate elevated C>A/G>T errors, and target-enrichment PCR led to ~ 6-fold increase of overall error rate. We also find that more than 70% of hotspot variants can be detected at 0.1 ~ 0.01% frequency with the current NGS technology by applying in silico error suppression. CONCLUSIONS: We present the first comprehensive analysis of sequencing error sources in conventional NGS workflows. The error profiles revealed by our study highlight new directions for further improving NGS analysis accuracy both experimentally and computationally, ultimately enhancing the precision of deep sequencing.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/normas , Neoplasias/genética , Reação em Cadeia da Polimerase/normas , Análise de Sequência de DNA/normas , Software , Estudos de Casos e Controles , Humanos , Mutação , Controle de Qualidade
8.
Leukemia ; 33(7): 1822-1827, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30755707

Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Diferenciação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/química , Regulação Neoplásica da Expressão Gênica , Leucemia/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Fusão Oncogênica/química , Proteína 1 Parceira de Translocação de RUNX1/química , Translocação Genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Humanos , Proteína 1 Inibidora de Diferenciação/genética , Proteína 1 Inibidora de Diferenciação/metabolismo , Leucemia/genética , Leucemia/metabolismo , Camundongos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/genética , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Proteína 1 de Leucemia Linfocítica Aguda de Células T/genética , Proteína 1 de Leucemia Linfocítica Aguda de Células T/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Arch Dis Child ; 104(6): 522-529, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30705079

RESUMO

OBJECTIVES: Before 2003, most children with acute lymphoblastic leukaemia (ALL) abandoned treatment, with only approximately 30% treated in China. With the development of national insurance for underprivileged patients, we assessed the current frequency and causes of treatment abandonment among patients with ALL who were enrolled in the Chinese Children's Cancer Group ALL protocol between 2015 and 2016. METHODS: Demographic, clinical and laboratory data on patients who abandoned treatment, as well as economic and sociocultural data of their families were collected and analysed. General health-related statistics were retrieved from publicly accessible databanks maintained by the Chinese government. RESULTS: At a median follow-up of 119 weeks, 83 (3.1%, 95% CI 2.5% to 3.8%) of the 2641 patients abandoned treatment. Factors independently associated with abandonment included standard/high-risk ALL (OR 2.62, 95% CI 1.43 to 4.77), presence of minimal residual disease at the end of remission induction (OR 3.57, 95% CI 1.90 to 6.74) and low-income economic region (OR 3.7, 95% CI 1.89 to 7.05). According to the family members, economic constraints (50.6%, p=0.0001) were the main reason for treatment abandonment, followed by the belief of incurability, severe side effects and concern over late complications. CONCLUSIONS: The rate of ALL treatment abandonment has been greatly reduced in China. Standard/high-risk ALL, residence in a low-income region and economic difficulties were associated with treatment abandonment. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR-IPR-14005706, pre-results.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Recusa do Paciente ao Tratamento/estatística & dados numéricos , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Criança , Pré-Escolar , China , Feminino , Seguimentos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Neoplasia Residual , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Indução de Remissão , Estudos Retrospectivos , Fatores Socioeconômicos
10.
ACS Nano ; 13(2): 2205-2212, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30694651

RESUMO

With rapid development of integrated circuits, urgent requirements for a transistor with lower subthreshold swing (SS) and better contact properties are needed. To optimize the SS and contact issues, we propose a concept of molybdenum disulfide (MoS2) filament transistor with two modes. We successfully fabricated the proposed devices in a wafer-scale. Mode I can enable the device with extremely low SS down to 2.26 mV/dec by switching the contact filament between on and off while mode II can realize a record high on/off ratio of 2.6 × 109 by using filament as quasi-zero dimensional (quasi-0D) contact. Compared to conventional three-dimensional (3D) contact, quasi-0D contact using conductive filament improves the current density nearly 50 times. We also built a spice model to simulate the electrical behaviors, and the simulation results show an extremely low SS in mode I (using abrupt filament formation/rupture) and excellent quasi-0D contact in mode II. The two-mode MoS2 filament transistor can significantly improve the SS and contact comparing to those of the state-of-the-art transistors, which has the great potential to boost the development of the next generation mainstream transistors.

11.
Front Med ; 13(3): 378-387, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30635781

RESUMO

Homoharringtonine (HHT), a plant alkaloid from Cephalotaxus harringtonia, exhibits a unique anticancer mechanism and has been widely used in China to treat patients with acute myeloid leukemia (AML) since the 1970s. Trial SCMC-AML-2009 presented herein was a randomized clinical study designed based on our previous findings that pediatric AML patients younger than two years old may benefit from HHT-containing chemotherapy regimens. Patients randomized to arm A were treated with a standard chemotherapy regimen comprising mainly of anthracyclines and cytarabine (Ara-C), whereas patients in arm B were treated with HHT-containing regimens in which anthracyclines in all but the initial induction therapy were replaced by HHT. From February 2009 to November 2015, 59 patients less than 2 years old with de novo AML (other than acute promyelocytic leukemia) were recruited. A total of 42 patients achieved a morphologic complete remission (CR) after the first course, with similar rates in both arms (70.6% vs.72.0%). At the end of the follow-up period, 40 patients remained in CR and 5 patients underwent hematopoietic stem cell transplantation in CR, which could not be considered as events but censors. The 5-year event-free survival (EFS) was 60.2%±9.6% for arm A and 88.0%±6.5% for arm B (P= 0.024). Patients in arm B experienced shorter durations of leukopenia, neutropenia, and thrombocytopenia and had a lower risk of infection during consolidation chemotherapy with high-dosage Ara-C. Consequently, the homoharringtonine-based regimen achieved excellent EFS and alleviated hematologic toxicity for children aged younger than 2 years with de novo AML compared with the anthracycline-based regimen.


Assuntos
Antraciclinas/uso terapêutico , Citarabina/uso terapêutico , Mepesuccinato de Omacetaxina/uso terapêutico , Leucemia Mieloide Aguda/terapia , Terapia Neoadjuvante , China , Intervalo Livre de Doença , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Leucemia Mieloide Aguda/mortalidade , Masculino , Indução de Remissão
12.
Int J Cancer ; 144(1): 117-124, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30098202

RESUMO

Langerhans cell histiocytosis (LCH) is the most common histiocytosis with constitutive activation of the RAS-RAF-MEK-ERK (MAPKinase) cell signaling pathway. We analyzed 89 cases of BRAF and MAP2K1 mutations by Sanger sequencing, of which 18 cases showed that these two gene mutations are negative. Whole genome sequencing of suitable specimens in these negative cases revealed a translocation from the 3 intron of PLEKHA6 to the 13 intron of NTRK3 in one case. We identified that this translocation could cause a novel fusion mutation, PLEKHA6-NTRK3. Overexpression of the PLEKHA6-NTRK3 mutant in NIH 3T3 cells enhanced MAPKinase pathway activation, promote cell growth. Our result suggested that a new mutation need be included in LCH molecular screening panel to better define its prevalence in LCH.


Assuntos
Histiocitose de Células de Langerhans/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Receptor trkC/genética , Proteínas Recombinantes de Fusão/genética , Adolescente , Animais , Proliferação de Células/genética , Criança , Pré-Escolar , Feminino , Histiocitose de Células de Langerhans/patologia , Humanos , Lactente , Masculino , Camundongos , Mutação , Células NIH 3T3
13.
Leukemia ; 33(6): 1387-1399, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30575821

RESUMO

Acute promyelocytic leukemia (APL) is characterized by t(15;17)(q22;q21), resulting in a PML-RARA fusion that is the master driver of APL. A few cases that cannot be identified with PML-RARA by using conventional methods (karyotype analysis, FISH, and RT-PCR) involve abnormal promyelocytes that are fully in accordance with APL in morphology, cytochemistry, and immunophenotype. To explore the mechanisms involved in pathogenesis and recurrence of morphologically diagnosed APL, we performed comprehensive variant analysis by next-generation sequencing in 111 pediatric patients morphologically diagnosed as APL. Structural variant (SV) analysis in 120 DNA samples from both diagnosis and relapse stage identified 95 samples with RARA rearrangement (including 94 with PML-RARA and one with NPM-RARA) and two samples with KMT2A rearrangement. In the eligible 13 RNA samples without any RARA rearrangement at diagnosis, one case each with CPSF6-RARG, NPM1-CCDC28A, and TBC1D15-RAB21 and two cases with a TBL1XR1-RARB fusion were discovered. These uncovered fusion genes strongly suggested their contributions to leukemogenesis as driver alternations and APL phenotype may arise by abnormalities of other members of the nuclear receptor superfamily involved in retinoid signaling (RARB or RARG) or even by mechanisms distinct from the formation of aberrant retinoid receptors. Single-nucleotide variant (SNV) analysis in 77 children (80 samples) with RARA rearrangement showed recurrent alternations of primary APL in FLT3, WT1, USP9X, NRAS, and ARID1A, with a strong potential for involvement in pathogenesis, and WT1 as the only recurrently mutated gene in relapsed APL. WT1, NPM1, NRAS, FLT3, and NSD1 were identified as recurrently mutated in 17 primary samples without RARA rearrangement and WT1, NPM1, TP53, and RARA as recurrently mutated in 9 relapsed samples. The survival of APL with RARA rearrangement is much better than without RARA rearrangement. Thus, patients morphologically diagnosed as APL that cannot be identified as having a RARA rearrangement are more reasonably classified as a subclass of AML other than APL, and individualized treatment should be considered according to the genetic abnormalities.


Assuntos
Biomarcadores Tumorais/genética , Células Precursoras de Granulócitos/patologia , Leucemia Promielocítica Aguda/genética , Mutação , Recidiva Local de Neoplasia/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células Precursoras de Granulócitos/metabolismo , Humanos , Lactente , Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/tratamento farmacológico , Masculino , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/tratamento farmacológico , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
14.
Proc Natl Acad Sci U S A ; 116(3): 890-899, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30593567

RESUMO

The AML1-ETO fusion protein, generated by the t(8;21) chromosomal translocation, is causally involved in nearly 20% of acute myeloid leukemia (AML) cases. In leukemic cells, AML1-ETO resides in and functions through a stable protein complex, AML1-ETO-containing transcription factor complex (AETFC), that contains multiple transcription (co)factors. Among these AETFC components, HEB and E2A, two members of the ubiquitously expressed E proteins, directly interact with AML1-ETO, confer new DNA-binding capacity to AETFC, and are essential for leukemogenesis. However, the third E protein, E2-2, is specifically silenced in AML1-ETO-expressing leukemic cells, suggesting E2-2 as a negative factor of leukemogenesis. Indeed, ectopic expression of E2-2 selectively inhibits the growth of AML1-ETO-expressing leukemic cells, and this inhibition requires the bHLH DNA-binding domain. RNA-seq and ChIP-seq analyses reveal that, despite some overlap, the three E proteins differentially regulate many target genes. In particular, studies show that E2-2 both redistributes AETFC to, and activates, some genes associated with dendritic cell differentiation and represses MYC target genes. In AML patients, the expression of E2-2 is relatively lower in the t(8;21) subtype, and an E2-2 target gene, THPO, is identified as a potential predictor of relapse. In a mouse model of human t(8;21) leukemia, E2-2 suppression accelerates leukemogenesis. Taken together, these results reveal that, in contrast to HEB and E2A, which facilitate AML1-ETO-mediated leukemogenesis, E2-2 compromises the function of AETFC and negatively regulates leukemogenesis. The three E proteins thus define a heterogeneity of AETFC, which improves our understanding of the precise mechanism of leukemogenesis and assists development of diagnostic/therapeutic strategies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Leucemia Mieloide Aguda/etiologia , Proteínas de Fusão Oncogênica/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/metabolismo , Recidiva
15.
Proc Natl Acad Sci U S A ; 115(50): E11711-E11720, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30487223

RESUMO

Most B cell precursor acute lymphoblastic leukemia (BCP ALL) can be classified into known major genetic subtypes, while a substantial proportion of BCP ALL remains poorly characterized in relation to its underlying genomic abnormalities. We therefore initiated a large-scale international study to reanalyze and delineate the transcriptome landscape of 1,223 BCP ALL cases using RNA sequencing. Fourteen BCP ALL gene expression subgroups (G1 to G14) were identified. Apart from extending eight previously described subgroups (G1 to G8 associated with MEF2D fusions, TCF3-PBX1 fusions, ETV6-RUNX1-positive/ETV6-RUNX1-like, DUX4 fusions, ZNF384 fusions, BCR-ABL1/Ph-like, high hyperdiploidy, and KMT2A fusions), we defined six additional gene expression subgroups: G9 was associated with both PAX5 and CRLF2 fusions; G10 and G11 with mutations in PAX5 (p.P80R) and IKZF1 (p.N159Y), respectively; G12 with IGH-CEBPE fusion and mutations in ZEB2 (p.H1038R); and G13 and G14 with TCF3/4-HLF and NUTM1 fusions, respectively. In pediatric BCP ALL, subgroups G2 to G5 and G7 (51 to 65/67 chromosomes) were associated with low-risk, G7 (with ≤50 chromosomes) and G9 were intermediate-risk, whereas G1, G6, and G8 were defined as high-risk subgroups. In adult BCP ALL, G1, G2, G6, and G8 were associated with high risk, while G4, G5, and G7 had relatively favorable outcomes. This large-scale transcriptome sequence analysis of BCP ALL revealed distinct molecular subgroups that reflect discrete pathways of BCP ALL, informing disease classification and prognostic stratification. The combined results strongly advocate that RNA sequencing be introduced into the clinical diagnostic workup of BCP ALL.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B/classificação , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Transcriptoma , Adulto , Criança , Bases de Dados de Ácidos Nucleicos , Feminino , Humanos , Masculino , Modelos Genéticos , Mutação , Fusão Oncogênica , Proteínas de Fusão Oncogênica/genética , Prognóstico , Análise de Sequência de RNA
16.
Hematol Oncol ; 36(4): 679-688, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30133806

RESUMO

Long-term follow-up data for childhood acute lymphoblastic leukemia (ALL) are scarce in China because of lacking population-based and hospitalized registry system. This retrospective study, conducted at Shanghai's Children's Medical Center in China (SCMC), aimed to investigate the long-term results of childhood ALL and to identify prognostic factors. The Pediatric Oncology Network Database, designed by St. Jude Children's Research Hospital, USA, were used to collect data for the enrolled patients starting in 2005. From 2005 to 2014, 1085 evaluable patients with ALL aged 1 to 18 years old were enrolled and treated using SCMC-ALL-2005 risk-stratified protocol. Complete remission was achieved in 95.6% of patients. At 5 and 10 years, the event-free survival rate was 68.3 ± 1.4% and 64.6 ± 1.6%, and the overall survival rate was 80.0 ± 1.2% and 76.3 ± 1.6%, respectively. The 5-year event-free survival rates were 81.8 ± 2.0%, 67.0 ± 1.9%, and 14.3 ± 4.0% for patients in low-risk, intermediate-risk, and high-risk groups, respectively. The cumulative risk of relapse was 24.5% at 10 years. Induction failure conferred worse prognosis. Patients younger than 1 year of age at diagnosis, intermediate-risk/high-risk group, male gender, and positive minimal residual disease (MRD) results at day 55, both in the univariate and multivariate analysis, were associated with significantly worse prognosis (P < .05). Patients with positive MRD at both day 35 and day 55 were related to a significantly poor outcome (P < .0001), but not for patients with negitive MRD at day 35. The overall outcomes for ALL patients treated with protocol SCMC-ALL-2005 in SCMC are lower than in developed countries. Factors including age, gender, risk group and MRD results at day 55 were associated with treatment outcomes in childhood ALL.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , China/epidemiologia , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Sistema de Registros , Estudos Retrospectivos , Resultado do Tratamento
17.
Pediatr Blood Cancer ; 65(10): e27266, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29943896

RESUMO

BACKGROUND: Mixed-lineage leukemia (MLL) with multifarious partner genes leads to aggressive leukemia with dismal outcomes. METHODS: Using panel-based targeted sequencing, we examined 90 cases with MLL-rearranged (MLL-r) childhood acute leukemia, including 55 with acute lymphoblastic leukemia (ALL) and 35 with acute myeloid leukemia (AML). RESULTS: MLL breakpoints and complete rearrangements were identified. A total of 37.8% (34/90) of patients displayed a single direct MLL fusion gene, 15.6% (14/90) carried a single reciprocal fusion, and 27.8% (25/90) had both reciprocal MLL fusion alleles. The remaining 17 MLL-r cases exhibited complex translocations with homozygous disruptions on chromosome 11 or two breakpoints on the same MLL allele with a deletion of functional regions. A total of 77 patients (45 ALL and 32 AML) received chemotherapy with a median follow-up of 2.5 years. Unexpectedly, we identified children with reciprocal MLL fusions who exhibited relatively favorable outcomes compared with those in children with complex translocations or a single direct MLL fusion allele (66.1% vs. 24.6% and 27.6%, P = 0.001). Reciprocal MLL fusion may be functionally rescued by a partially truncated MLL protein. CONCLUSION: Comprehensive MLL-r analysis by targeted next-generation sequencing can provide detailed molecular information and is helpful for precise stratified treatment and clinical prognosis determination.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Criança , Pré-Escolar , Feminino , Rearranjo Gênico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Intervalo Livre de Progressão , Translocação Genética
18.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(9): 1027-1033, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-28899477

RESUMO

Mercaptopurine is a common chemotherapeutic drug and immunosuppressive agent and plays an important role in the treatment of acute lymphoblastic leukemia and inflammatory bowel disease. It may cause severe adverse effects such as myelosuppression, which may result in the interruption of treatment or complications including infection or even threaten patients' lives. However, the adverse effects of mercaptopurine show significant racial and individual differences, which reveal the important role of genetic diversity. Recent research advances in pharmacogenomics have gradually revealed the genetic nature of such differences. This article reviews the recent research advances in the pharmacogenomics and individualized application of mercaptopurine.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Mercaptopurina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Humanos , Mercaptopurina/metabolismo , Metiltransferases/genética , Farmacogenética , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Pirofosfatases/genética
20.
J Cancer Res Clin Oncol ; 143(7): 1327-1335, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28283783

RESUMO

This retrospective study evaluated the long-term outcomes and prognostic indicators of patients with stage 4 neuroblastoma who were older than 18 months at diagnosis. The medical records of 118 such children who were treated at Shanghai Children's Medical Center, China, from June 1998-December 2013 were reviewed. Event-free survival (EFS) and overall survival (OS) were analyzed by log-rank tests. Of the 118 patients, 14 improving patients did not complete treatment because of parental decisions, and 1 patient died during surgery. Of the 103 patients who completed the comprehensive protocols, 60 (58.3%) achieved very good partial remission (VGPR), 26 (25.2%) achieved partial remission (PR) after four courses of chemotherapy, and 17 (16.5%) progressed during treatment. The response to induction (including VGPR + PR) was 83.5%. After a median follow-up of 105 months (range 36-160 months), the 5- and 10-year OS were 21 and 18%, and the EFS was 19 and 13%, respectively. EFS was significantly better for patients with normal levels of urinary vanillylmandelic acid (VMA) at diagnosis, who had complete resection of the primary tumor, who were minimal residual disease- (MRD-) negative in their bone marrow after four courses of chemotherapy, and who achieved VGPR at the end of treatment (P < 0.05). The prognosis remains poor for patients with stage 4 neuroblastoma who are older than 18 months at diagnosis. Elevated VMA level, incomplete tumor resection, persistent MRD in bone marrow, and poor curative effect are associated with worse prognosis.


Assuntos
Neuroblastoma/mortalidade , Neuroblastoma/patologia , Neuroblastoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , China , Intervalo Livre de Doença , Feminino , Citometria de Fluxo , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Análise Multivariada , Neoplasia Residual/mortalidade , Neoplasia Residual/patologia , Transplante de Células-Tronco de Sangue Periférico , Prognóstico , Modelos de Riscos Proporcionais , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Ácido Vanilmandélico/urina
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