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PURPOSE: This study aimed to understand the experience of families caring for a child with cancer in New Zealand (NZ) who received nutrition and dietetic support during cancer treatment and their preferences for the delivery, format, and timing of nutrition information. METHODS: Childhood cancer patients and their families (N = 21) participated in a mixed-methods study at a specialist paediatric oncology centre in Auckland, NZ. Before the semi-structured interview, participants completed a questionnaire capturing demographic, disease, and treatment characteristics of their child, their nutrition concerns, and their information needs. Quantitative data were described, and qualitative thematic analysis of the semi-structured interviews was performed using NVivo data analysis software. RESULTS: Eighty-six percent of participants indicated they had concerns about their child's nutrition during treatment. The most common concerns were anorexia, vomiting, and weight loss. While many were happy with the quality of the nutrition support received, one-third of the patients wanted more support. Four key themes emerged from the interviews: (1) patients experience significant and distressing nutrition challenges; (2) patients and families have mixed perceptions of EN; (3) there are gaps in the current nutrition support system for inpatients; and (4) a desire for more accessible nutrition support. CONCLUSION: Childhood cancer patients and families experience significant and distressing nutrition challenges during treatment. Standardising information given to patients and their families may optimise nutrition support for paediatric oncology patients and reduce the discordance between families and health professionals. Future implementation of a nutrition decision aid in this population is warranted.
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Dietética , Neoplasias , Humanos , Criança , Neoplasias/terapia , Pacientes Internados , Estado Nutricional , Oncologia , Pesquisa QualitativaRESUMO
BACKGROUND: High-risk pediatric acute myeloid leukemia confers a poor prognosis, and alternative strategies are needed to improve outcomes. We hypothesized that intensifying induction on the AAML1031 clinical trial would improve outcomes compared to the predecessor trial AAML0531. METHODS: Patients on AAML0531 received cytarabine (1600 mg/m2 )/daunorubicin (150 mg/m2 )/etoposide (ADE) for induction II and patients on AAML1031 received mitoxantrone (48 mg/m2 )/cytarabine (8000 mg/m2 ) (MA). Stem cell transplant (SCT) conditioning included busulfan/cyclophosphamide on AAML0531, whereas AAML1031 used busulfan/fludarabine and liberalized donor eligibility. Patients were included in this analysis if they met high-risk criteria common to the two trials by cytogenics or poor disease response after induction I ADE. RESULTS: MA provided no benefit over ADE at: induction II response (complete response [CR]: 64% vs. 62%, p = .87; measurable residual disease [MRD]+: 57% vs. 46%, p = .34); or intensification I response (CR: 79% vs. 94%, p = .27; MRD+: 27% vs. 20%, p = 1.0). When considered with altered SCT approach, MA did not improve 5-year disease-free survival (24% ± 9% vs. 18% ± 15%, p = .63) or 5-year overall survival (35% ± 10% vs. 38% ± 18%, p = .66). MA was associated with slower neutrophil recovery (median 34 vs. 27 days, p = .007) and platelet recovery (median 29 vs. 24.5 days, p = .04) and longer hospital stay (32 vs. 28 days, p = .01) during induction II. CONCLUSION: Intensification of induction II did not improve treatment response or survival, but did increase toxicity and resource utilization. Alternative strategies are urgently needed to improve outcomes for pediatric patients with high-risk acute myeloid leukemia (trials registered at clinicaltrials.gov NCT01371981, NCT00372593).
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Quimioterapia de Indução , Leucemia Mieloide Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bussulfano/uso terapêutico , Criança , Ensaios Clínicos como Assunto , Citarabina/uso terapêutico , Intervalo Livre de Doença , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/etiologia , Neoplasia Residual/tratamento farmacológico , Resultado do TratamentoRESUMO
Neuroblastoma is a paediatric malignancy that typically arises in early childhood, and is derived from the developing sympathetic nervous system. Clinical phenotypes range from localized tumours with excellent outcomes to widely metastatic disease in which long-term survival is approximately 40% despite intensive therapy. A previous genome-wide association study identified common polymorphisms at the LMO1 gene locus that are highly associated with neuroblastoma susceptibility and oncogenic addiction to LMO1 in the tumour cells. Here we investigate the causal DNA variant at this locus and the mechanism by which it leads to neuroblastoma tumorigenesis. We first imputed all possible genotypes across the LMO1 locus and then mapped highly associated single nucleotide polymorphism (SNPs) to areas of chromatin accessibility, evolutionary conservation and transcription factor binding sites. We show that SNP rs2168101 G>T is the most highly associated variant (combined P = 7.47 × 10(-29), odds ratio 0.65, 95% confidence interval 0.60-0.70), and resides in a super-enhancer defined by extensive acetylation of histone H3 lysine 27 within the first intron of LMO1. The ancestral G allele that is associated with tumour formation resides in a conserved GATA transcription factor binding motif. We show that the newly evolved protective TATA allele is associated with decreased total LMO1 expression (P = 0.028) in neuroblastoma primary tumours, and ablates GATA3 binding (P < 0.0001). We demonstrate allelic imbalance favouring the G-containing strand in tumours heterozygous for this SNP, as demonstrated both by RNA sequencing (P < 0.0001) and reporter assays (P = 0.002). These findings indicate that a recently evolved polymorphism within a super-enhancer element in the first intron of LMO1 influences neuroblastoma susceptibility through differential GATA transcription factor binding and direct modulation of LMO1 expression in cis, and this leads to an oncogenic dependency in tumour cells.
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Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos/genética , Predisposição Genética para Doença/genética , Proteínas com Domínio LIM/genética , Neuroblastoma/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição/genética , Acetilação , Alelos , Desequilíbrio Alélico , Sítios de Ligação , Epigenômica , Fator de Transcrição GATA3/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Genótipo , Histonas/química , Histonas/metabolismo , Humanos , Íntrons/genética , Lisina/metabolismo , Especificidade de Órgãos , Reprodutibilidade dos TestesRESUMO
Lytic transglycosylases such as Slt35 from E. coli are enzymes involved in bacterial cell wall remodelling and recycling, which represent potential targets for novel antibacterial agents. Here, we investigated a series of known glycosidase inhibitors for their ability to inhibit Slt35. While glycosidase inhibitors such as 1-deoxynojirimycin, castanospermine, thiamet G and miglitol had no effect, the phenothiazinium dye thionine acetate was found to be a weak inhibitor. IC50 values and binding constants for thionine acetate were similar for Slt35 and the hen egg white lysozyme. Molecular docking simulations suggest that thionine binds to the active site of both Slt35 and lysozyme, although it does not make direct interactions with the side-chain of the catalytic Asp and Glu residues as might be expected based on other inhibitors. Thionine acetate also increased the potency of the beta-lactam antibiotic ampicillin against a laboratory strain of E. coli.
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Glicosiltransferases/metabolismo , Fenotiazinas/farmacologia , Acetatos/metabolismo , Sequência de Aminoácidos/genética , Proteínas de Bactérias/química , Sítios de Ligação/genética , Domínio Catalítico/genética , Parede Celular/metabolismo , Cristalografia por Raios X/métodos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/metabolismo , Glicosiltransferases/antagonistas & inibidores , Glicosiltransferases/efeitos dos fármacos , Modelos Moleculares , Simulação de Acoplamento Molecular , Muramidase/antagonistas & inibidores , Muramidase/metabolismo , Peptidoglicano/metabolismo , Fenotiazinas/metabolismo , Conformação Proteica/efeitos dos fármacosRESUMO
Pseudomonas mesoacidophila ATCC 31433 is a Gram-negative bacterium, first isolated from Japanese soil samples, that produces the monobactam isosulfazecin and the ß-lactam-potentiating bulgecins. To characterize the biosynthetic potential of P. mesoacidophila ATCC 31433, its complete genome was determined using single-molecule real-time DNA sequence analysis. The 7.8-Mb genome comprised four replicons, three chromosomal (each encoding rRNA) and one plasmid. Phylogenetic analysis demonstrated that P. mesoacidophila ATCC 31433 was misclassified at the time of its deposition and is a member of the Burkholderia cepacia complex, most closely related to Burkholderia ubonensis The sequenced genome shows considerable additional biosynthetic potential; known gene clusters for malleilactone, ornibactin, isosulfazecin, alkylhydroxyquinoline, and pyrrolnitrin biosynthesis and several uncharacterized biosynthetic gene clusters for polyketides, nonribosomal peptides, and other metabolites were identified. Furthermore, P. mesoacidophila ATCC 31433 harbors many genes associated with environmental resilience and antibiotic resistance and was resistant to a range of antibiotics and metal ions. In summary, this bioactive strain should be designated B. cepacia complex strain ATCC 31433, pending further detailed taxonomic characterization.IMPORTANCE This work reports the complete genome sequence of Pseudomonas mesoacidophila ATCC 31433, a known producer of bioactive compounds. Large numbers of both known and novel biosynthetic gene clusters were identified, indicating that P. mesoacidophila ATCC 31433 is an untapped resource for discovery of novel bioactive compounds. Phylogenetic analysis demonstrated that P. mesoacidophila ATCC 31433 is in fact a member of the Burkholderia cepacia complex, most closely related to the species Burkholderia ubonensis Further investigation of the classification and biosynthetic potential of P. mesoacidophila ATCC 31433 is warranted.
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Complexo Burkholderia cepacia/genética , Pseudomonas/genética , Antibacterianos/farmacologia , Complexo Burkholderia cepacia/classificação , Complexo Burkholderia cepacia/efeitos dos fármacos , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica/fisiologia , Genoma Bacteriano/genética , Filogenia , Pseudomonas/classificação , Pseudomonas/efeitos dos fármacosRESUMO
Early T-cell precursor (ETP) acute lymphoblastic leukemia (ALL) is a recently described subtype of T-ALL characterized by a unique immunophenotype and genomic profile, as well as a high rate of induction failure. Frequent mutations in cytokine receptor and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathways led us to hypothesize that ETP-ALL is dependent on JAK/STAT signaling. Here we demonstrate aberrant activation of the JAK/STAT pathway in ETP-ALL blasts relative to non-ETP T-ALL. Moreover, ETP-ALL showed hyperactivation of STAT5 in response to interleukin-7, an effect that was abrogated by the JAK1/2 inhibitor ruxolitinib. In vivo, ruxolitinib displayed activity in 6 of 6 patient-derived murine xenograft models of ETP-ALL, with profound single-agent efficacy in 5 models. Ruxolitinib treatment decreased peripheral blast counts relative to pretreatment levels and compared with control (P < .01) in 5 of 6 ETP-ALL xenografts, with marked reduction in mean splenic blast counts (P < .01) in 6 of 6 samples. Surprisingly, both JAK/STAT pathway activation and ruxolitinib efficacy were independent of the presence of JAK/STAT pathway mutations, raising the possibility that the therapeutic potential of ruxolitinib in ETP-ALL extends beyond those cases with JAK mutations. These findings establish the preclinical in vivo efficacy of ruxolitinib in ETP-ALL, a biologically distinct subtype for which novel therapies are needed.
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Janus Quinases/antagonistas & inibidores , Células Precursoras de Linfócitos T/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Fatores de Transcrição STAT/antagonistas & inibidores , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Humanos , Interleucina-7/metabolismo , Janus Quinases/genética , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Nitrilas , Células Precursoras de Linfócitos T/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirazóis/farmacologia , Pirimidinas , Fatores de Transcrição STAT/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto JovemRESUMO
Neuroblastoma is a childhood cancer that is often fatal despite intense multimodality therapy. In an effort to identify therapeutic targets for this disease, we performed a comprehensive loss-of-function screen of the protein kinome. Thirty kinases showed significant cellular cytotoxicity when depleted, with loss of the cell cycle checkpoint kinase 1 (CHK1/CHEK1) being the most potent. CHK1 mRNA expression was higher in MYC-Neuroblastoma-related (MYCN)-amplified (P < 0.0001) and high-risk (P = 0.03) tumors. Western blotting revealed that CHK1 was constitutively phosphorylated at the ataxia telangiectasia response kinase target site Ser345 and the autophosphorylation site Ser296 in neuroblastoma cell lines. This pattern was also seen in six of eight high-risk primary tumors but not in control nonneuroblastoma cell lines or in seven of eight low-risk primary tumors. Neuroblastoma cells were sensitive to the two CHK1 inhibitors SB21807 and TCS2312, with median IC(50) values of 564 nM and 548 nM, respectively. In contrast, the control lines had high micromolar IC(50) values, indicating a strong correlation between CHK1 phosphorylation and CHK1 inhibitor sensitivity (P = 0.0004). Furthermore, cell cycle analysis revealed that CHK1 inhibition in neuroblastoma cells caused apoptosis during S-phase, consistent with its role in replication fork progression. CHK1 inhibitor sensitivity correlated with total MYC(N) protein levels, and inducing MYCN in retinal pigmented epithelial cells resulted in CHK1 phosphorylation, which caused growth inhibition when inhibited. These data show the power of a functional RNAi screen to identify tractable therapeutical targets in neuroblastoma and support CHK1 inhibition strategies in this disease.
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Neuroblastoma/tratamento farmacológico , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Interferente Pequeno/farmacologia , Apoptose/efeitos dos fármacos , Quinase 1 do Ponto de Checagem , Sistemas de Liberação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Humanos , Proteína Proto-Oncogênica N-Myc , Neuroblastoma/patologia , Proteínas Nucleares/análise , Proteínas Oncogênicas/análise , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro , Fase S/efeitos dos fármacosRESUMO
RUNX1::RUNX1T1 (R::RT1) Acute Myeloid Leukaemia (AML) remains a clinical challenge, and further research is required to model and understand leukaemogenesis. Previous zebrafish R::RT1 models were hampered by embryonic lethality and low penetrance of the malignant phenotype. Here, we overcome this by developing an adult zebrafish model in which the human R::RT1 isoform 9a is co-expressed with the frequently co-occurring oncogenic NRASG12D mutation in haematopoietic stem and progenitor cells (HSPCs), using the Runx1+23 enhancer. Approximately 50% of F0 9a+NRASG12D transgenic zebrafish developed signs of haematological disease between 5 and 14 months, with 27% exhibiting AML-like pathology: myeloid precursor expansion, erythrocyte reduction, kidney marrow hypercellularity and the presence of blasts. Moreover, only 9a+NRASG12D transplant recipients developed leukaemia with high rates of mortality within 40 days, inferring the presence of leukaemia stem cells. These leukaemic features were rare or not observed in animals expressing either the NRAS or 9a oncogenes alone, suggesting 9a and NRAS cooperation drives leukaemogenesis. This novel adult AML zebrafish model provides a powerful new tool for investigating the basis of R::RT1 - NRAS cooperativity with the potential to uncover new therapeutic targets.
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BACKGROUND: IMGN901 (lorvotuzumab mertansine) is an antibody-drug conjugate composed of a humanized antibody that specifically binds to CD56 (NCAM, neural cell adhesion molecule) and that is conjugated to the maytansinoid, DM1 (a microtubule targeting agent). PROCEDURES: IMGN901 and DM1-SMe (unconjugated DM1 as a mixed disulfide with thiomethane to cap its sulfhydryl group) were tested in vitro at concentrations ranging from 0.01 nM to 0.1 µM and 0.3 pM to 3 nM, respectively. IMGN901 was tested against a subset of PPTP solid tumor xenografts focusing on those with high CD56 expression.The combination of IMGN901 with topotecan was also evaluated. RESULTS: Neuroblastoma models expressed CD56 at or above the median expression level for all PPTP xenografts and cell lines. Neuroblastoma cell lines demonstrated relatively low sensitivity to DM1-SMe compared to other cell lines, but the sensitivity of neuroblastoma cell lines to IMGN901 was comparable to that of non-neuroblastoma cell lines. In vivo, objective responses were observed in 9 of 24 (38%) models including, three of seven neuroblastoma xenografts, and two of seven rhabdomyosarcoma xenografts. All xenografts with objective responses showed homogeneous high-level staining by IHC for CD56, but not all xenografts with homogenous high-level staining had objective responses. Combined with topotecan, IMGN901 demonstrated therapeutic enhancement against two of four neuroblastoma models. CONCLUSIONS: IMGN901 has anti-tumor activity against some CD56 expressing pediatric cancer models. High expression of CD56 is a biomarker for in vivo response, but resistance mechanisms to IMGN901 in some high CD56 expressing lines need to be defined.
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Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Maitansina/análogos & derivados , Neoplasias Experimentais/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Imuno-Histoquímica , Maitansina/farmacologia , Camundongos , Camundongos SCID , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Childhood neuroblastomas exhibit plasticity between an undifferentiated neural crest-like "mesenchymal" cell state and a more differentiated sympathetic "adrenergic" cell state. These cell states are governed by autoregulatory transcriptional loops called core regulatory circuitries (CRCs), which drive the early development of sympathetic neuronal progenitors from migratory neural crest cells during embryogenesis. The adrenergic cell identity of neuroblastoma requires LMO1 as a transcriptional co-factor. Both LMO1 expression levels and the risk of developing neuroblastoma in children are associated with a single nucleotide polymorphism G/T that affects a G ATA motif in the first intron of LMO1. Here we show that wild-type zebrafish with the G ATA genotype develop adrenergic neuroblastoma, while knock-in of the protective T ATA allele at this locus reduces the penetrance of MYCN-driven tumors, which are restricted to the mesenchymal cell state. Whole genome sequencing of childhood neuroblastomas demonstrates that T ATA/ T ATA tumors also exhibit a mesenchymal cell state and are low risk at diagnosis. Thus, conversion of the regulatory G ATA to a T ATA allele in the first intron of LMO1 reduces the neuroblastoma initiation rate by preventing formation of the adrenergic cell state, a mechanism that is conserved over 400 million years of evolution separating zebrafish and humans.
RESUMO
Childhood neuroblastomas exhibit plasticity between an undifferentiated neural crest-like mesenchymal cell state and a more differentiated sympathetic adrenergic cell state. These cell states are governed by autoregulatory transcriptional loops called core regulatory circuitries (CRCs), which drive the early development of sympathetic neuronal progenitors from migratory neural crest cells during embryogenesis. The adrenergic cell identity of neuroblastoma requires LMO1 as a transcriptional cofactor. Both LMO1 expression levels and the risk of developing neuroblastoma in children are associated with a single nucleotide polymorphism, G/T, that affects a GATA motif in the first intron of LMO1. Here, we showed that WT zebrafish with the GATA genotype developed adrenergic neuroblastoma, while knock-in of the protective TATA allele at this locus reduced the penetrance of MYCN-driven tumors, which were restricted to the mesenchymal cell state. Whole genome sequencing of childhood neuroblastomas demonstrated that TATA/TATA tumors also exhibited a mesenchymal cell state and were low risk at diagnosis. Thus, conversion of the regulatory GATA to a TATA allele in the first intron of LMO1 reduced the neuroblastoma-initiation rate by preventing formation of the adrenergic cell state. This mechanism was conserved over 400 million years of evolution, separating zebrafish and humans.
Assuntos
Predisposição Genética para Doença , Neuroblastoma , Animais , Criança , Humanos , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Adrenérgicos , Genótipo , Neuroblastoma/patologia , Proteína Proto-Oncogênica N-Myc/genéticaRESUMO
Ewing sarcoma is a pediatric bone cancer defined by a chromosomal translocation fusing one of the FET family members to an ETS transcription factor. There have been seven reported chromosomal translocations, with the most recent reported over a decade ago. We now report a novel FET/ETS translocation involving FUS and ETV4 detected in a patient with Ewing sarcoma. Here, we characterized FUS/ETV4 by performing genomic localization and transcriptional regulatory studies on numerous FET/ETS fusions in a Ewing sarcoma cellular model. Through this comparative analysis, we demonstrate significant similarities across these fusions, and in doing so, validate FUS/ETV4 as a bona fide Ewing sarcoma translocation. This study presents the first genomic comparison of Ewing sarcoma-associated translocations and reveals that the FET/ETS fusions share highly similar, but not identical, genomic localization and transcriptional regulation patterns. These data strengthen the notion that FET/ETS fusions are key drivers of, and thus pathognomonic for, Ewing sarcoma. IMPLICATIONS: Identification and initial characterization of the novel Ewing sarcoma fusion, FUS/ETV4, expands the family of Ewing fusions and extends the diagnostic possibilities for this aggressive tumor of adolescents and young adults.
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Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Sarcoma de Ewing/genética , Translocação Genética/genética , Humanos , Recém-Nascido , Proteínas de Fusão Oncogênica/genética , Sarcoma de Ewing/patologiaRESUMO
PURPOSE: Before anaplastic lymphoma kinase (ALK) inhibitors, treatment options for ALK-positive inflammatory myofibroblastic tumors (AP-IMTs) were unsatisfactory. We retrospectively analyzed the outcome of patients with AP-IMT treated with crizotinib to document response, toxicity, survival, and features associated with relapse. METHODS: The cohort comprised eight patients with AP-IMT treated with crizotinib and surgery. Outcome measures were progression-free and overall survival after commencing crizotinib, treatment-related toxicities, features associated with relapse, outcome after relapse, and outcome after ceasing crizotinib. RESULTS: The median follow-up after commencing crizotinib was 3 years (range, 0.9 to 5.5 years). The major toxicity was neutropenia. All patients responded to crizotinib. Five were able to discontinue therapy without recurrence (median treatment duration, 1 year; range, 0.2 to 3.0 years); one continues on crizotinib. Two critically ill patients with initial complete response experienced relapse while on therapy. Both harbored RANBP2-ALK fusions and responded to alternative ALK inhibitors; one ultimately died as a result of progressive disease, whereas the other remains alive on treatment. Progression-free and overall survival since commencement of crizotinib is 0.75 ± 0.15% and 0.83 ± 0.15%, respectively. CONCLUSION: We confirm acceptable toxicity and excellent disease control in patients with AP-IMT treated with crizotinib, which may be ceased without recurrence in most. Relapses occurred in two of three patients with RANBP2-ALK translocated IMT, which suggests that such patients require additional therapy.
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Purpose: Anaplastic lymphoma kinase (ALK) is the most frequently mutated oncogene in the pediatric cancer neuroblastoma. We performed an in vitro screen for synergistic drug combinations that target neuroblastomas with mutations in ALK to determine whether drug combinations could enhance antitumor efficacy.Experimental Design: We screened combinations of eight molecularly targeted agents against 17 comprehensively characterized human neuroblastoma-derived cell lines. We investigated the combination of ceritinib and ribociclib on in vitro proliferation, cell cycle, viability, caspase activation, and the cyclin D/CDK4/CDK6/RB and pALK signaling networks in cell lines with representative ALK status. We performed in vivo trials in CB17 SCID mice bearing conventional and patient-derived xenograft models comparing ceritinib alone, ribociclib alone, and the combination, with plasma pharmacokinetics to evaluate for drug-drug interactions.Results: The combination of ribociclib, a dual inhibitor of cyclin-dependent kinase (CDK) 4 and 6, and the ALK inhibitor ceritinib demonstrated higher cytotoxicity (P = 0.008) and synergy scores (P = 0.006) in cell lines with ALK mutations as compared with cell lines lacking mutations or alterations in ALK Compared with either drug alone, combination therapy enhanced growth inhibition, cell-cycle arrest, and caspase-independent cell death. Combination therapy achieved complete regressions in neuroblastoma xenografts with ALK-F1174L and F1245C de novo resistance mutations and prevented the emergence of resistance. Murine ribociclib and ceritinib plasma concentrations were unaltered by combination therapy.Conclusions: This preclinical combination drug screen with in vivo validation has provided the rationale for a first-in-children trial of combination ceritinib and ribociclib in a molecularly selected pediatric population. Clin Cancer Res; 23(11); 2856-68. ©2016 AACR.
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Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Aminopiridinas/administração & dosagem , Quinase do Linfoma Anaplásico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/genética , Sinergismo Farmacológico , Humanos , Camundongos , Mutação , Neuroblastoma/genética , Neuroblastoma/patologia , Purinas/administração & dosagem , Pirimidinas/administração & dosagem , Receptores Proteína Tirosina Quinases/genética , Proteína do Retinoblastoma/genética , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Sulfonas/administração & dosagem , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A genome-wide association study identified LMO1, which encodes an LIM-domain-only transcriptional cofactor, as a neuroblastoma susceptibility gene that functions as an oncogene in high-risk neuroblastoma. Here we show that dßh promoter-mediated expression of LMO1 in zebrafish synergizes with MYCN to increase the proliferation of hyperplastic sympathoadrenal precursor cells, leading to a reduced latency and increased penetrance of neuroblastomagenesis. The transgenic expression of LMO1 also promoted hematogenous dissemination and distant metastasis, which was linked to neuroblastoma cell invasion and migration, and elevated expression levels of genes affecting tumor cell-extracellular matrix interaction, including loxl3, itga2b, itga3, and itga5. Our results provide in vivo validation of LMO1 as an important oncogene that promotes neuroblastoma initiation, progression, and widespread metastatic dissemination.
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Carcinogênese/patologia , Proteínas de Ligação a DNA/metabolismo , Proteínas com Domínio LIM/metabolismo , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fatores de Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Matriz Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Hiperplasia , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica , Neuroblastoma/genética , Transdução de Sinais/genética , Transgenes , Peixe-ZebraRESUMO
Genetic studies have established anaplastic lymphoma kinase (ALK), a cell surface receptor tyrosine kinase, as a tractable molecular target in neuroblastoma. We describe comprehensive genomic, biochemical, and computational analyses of ALK mutations across 1,596 diagnostic neuroblastoma samples. ALK tyrosine kinase domain mutations occurred in 8% of samples--at three hot spots and 13 minor sites--and correlated significantly with poorer survival in high- and intermediate-risk neuroblastoma. Biochemical and computational studies distinguished oncogenic (constitutively activating) from nononcogenic mutations and allowed robust computational prediction of their effects. The mutated variants also showed differential in vitro crizotinib sensitivities. Our studies identify ALK genomic status as a clinically important therapeutic stratification tool in neuroblastoma and will allow tailoring of ALK-targeted therapy to specific mutations.
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Antineoplásicos/uso terapêutico , Neuroblastoma/genética , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico , Antineoplásicos/farmacologia , Crizotinibe , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos , Humanos , Ligação de Hidrogênio , Lactente , Estimativa de Kaplan-Meier , Cinética , Modelos Moleculares , Terapia de Alvo Molecular , Mutação de Sentido Incorreto , Neuroblastoma/tratamento farmacológico , Neuroblastoma/mortalidade , Oncogenes , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/químicaRESUMO
PURPOSE: Neuroblastoma is a pediatric cancer that continues to exact significant morbidity and mortality. Recently, a number of cell-cycle proteins, particularly those within the Cyclin D/CDK4/CDK6/RB network, have been shown to exert oncogenic roles in neuroblastoma, suggesting that their therapeutic exploitation might improve patient outcomes. EXPERIMENTAL PROCEDURES: We evaluated the effect of dual CDK4/CDK6 inhibition on neuroblastoma viability using LEE011 (Novartis Oncology), a highly specific CDK4/6 inhibitor. RESULTS: Treatment with LEE011 significantly reduced proliferation in 12 of 17 human neuroblastoma-derived cell lines by inducing cytostasis at nanomolar concentrations (mean IC50 = 307 ± 68 nmol/L in sensitive lines). LEE011 caused cell-cycle arrest and cellular senescence that was attributed to dose-dependent decreases in phosphorylated RB and FOXM1, respectively. In addition, responsiveness of neuroblastoma xenografts to LEE011 translated to the in vivo setting in that there was a direct correlation of in vitro IC50 values with degree of subcutaneous xenograft growth delay. Although our data indicate that neuroblastomas sensitive to LEE011 were more likely to contain genomic amplification of MYCN (P = 0.01), the identification of additional clinically accessible biomarkers is of high importance. CONCLUSIONS: Taken together, our data show that LEE011 is active in a large subset of neuroblastoma cell line and xenograft models, and supports the clinical development of this CDK4/6 inhibitor as a therapy for patients with this disease. Clin Cancer Res; 19(22); 6173-82. ©2013 AACR.
Assuntos
Aminopiridinas/farmacologia , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Purinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Criança , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/genética , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/metabolismo , Humanos , Camundongos , Camundongos SCID , Proteína Proto-Oncogênica N-Myc , Transplante de Neoplasias , Neuroblastoma/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Fosforilação/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único , Interferência de RNA , RNA Interferente Pequeno , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transplante HeterólogoRESUMO
Neuroblastoma is a malignancy of the developing sympathetic nervous system that often presents with widespread metastatic disease, resulting in survival rates of less than 50%. To determine the spectrum of somatic mutation in high-risk neuroblastoma, we studied 240 affected individuals (cases) using a combination of whole-exome, genome and transcriptome sequencing as part of the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative. Here we report a low median exonic mutation frequency of 0.60 per Mb (0.48 nonsilent) and notably few recurrently mutated genes in these tumors. Genes with significant somatic mutation frequencies included ALK (9.2% of cases), PTPN11 (2.9%), ATRX (2.5%, and an additional 7.1% had focal deletions), MYCN (1.7%, causing a recurrent p.Pro44Leu alteration) and NRAS (0.83%). Rare, potentially pathogenic germline variants were significantly enriched in ALK, CHEK2, PINK1 and BARD1. The relative paucity of recurrent somatic mutations in neuroblastoma challenges current therapeutic strategies that rely on frequently altered oncogenic drivers.
Assuntos
Exoma , Mutação , Neuroblastoma , Linhagem Celular Tumoral , Predisposição Genética para Doença , Genoma Humano , Humanos , Neuroblastoma/genética , Neuroblastoma/fisiopatologia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , TranscriptomaRESUMO
The mechanisms underlying genetic susceptibility at loci discovered by genome-wide association study (GWAS) approaches in human cancer remain largely undefined. In this study, we characterized the high-risk neuroblastoma association at the BRCA1-related locus, BARD1, showing that disease-associated variations correlate with increased expression of the oncogenically activated isoform, BARD1ß. In neuroblastoma cells, silencing of BARD1ß showed genotype-specific cytotoxic effects, including decreased substrate-adherence, anchorage-independence, and foci growth. In established murine fibroblasts, overexpression of BARD1ß was sufficient for neoplastic transformation. BARD1ß stabilized the Aurora family of kinases in neuroblastoma cells, suggesting both a mechanism for the observed effect and a potential therapeutic strategy. Together, our findings identify BARD1ß as an oncogenic driver of high-risk neuroblastoma tumorigenesis, and more generally, they illustrate how robust GWAS signals offer genomic landmarks to identify molecular mechanisms involved in both tumor initiation and malignant progression. The interaction of BARD1ß with the Aurora family of kinases lends strong support to the ongoing work to develop Aurora kinase inhibitors for clinically aggressive neuroblastoma.
Assuntos
Transformação Celular Neoplásica/genética , Predisposição Genética para Doença/genética , Neuroblastoma/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Animais , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Immunoblotting , Imunoprecipitação , Camundongos , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Isoformas de Proteínas/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de TecidosRESUMO
Activating mutations in the anaplastic lymphoma kinase (ALK) gene were recently discovered in neuroblastoma, a cancer of the developing autonomic nervous system that is the most commonly diagnosed malignancy in the first year of life. The most frequent ALK mutations in neuroblastoma cause amino acid substitutions (F1174L and R1275Q) in the intracellular tyrosine kinase domain of the intact ALK receptor. Identification of ALK as an oncogenic driver in neuroblastoma suggests that crizotinib (PF-02341066), a dual-specific inhibitor of the ALK and Met tyrosine kinases, will be useful in treating this malignancy. Here, we assessed the ability of crizotinib to inhibit proliferation of neuroblastoma cell lines and xenografts expressing mutated or wild-type ALK. Crizotinib inhibited proliferation of cell lines expressing either R1275Q-mutated ALK or amplified wild-type ALK. In contrast, cell lines harboring F1174L-mutated ALK were relatively resistant to crizotinib. Biochemical analyses revealed that this reduced susceptibility of F1174L-mutated ALK to crizotinib inhibition resulted from an increased adenosine triphosphate-binding affinity (as also seen in acquired resistance to epidermal growth factor receptor inhibitors). Thus, this effect should be surmountable with higher doses of crizotinib and/or with higher-affinity inhibitors.