Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
227 result(s) for "Maris, John M."
Sort by:
Enrichment of Targetable Mutations in the Relapsed Neuroblastoma Genome
Neuroblastoma is characterized by a relative paucity of recurrent somatic mutations at diagnosis. However, recent studies have shown that the mutational burden increases at relapse, likely as a result of clonal evolution of mutation-carrying cells during primary treatment. To inform the development of personalized therapies, we sought to further define the frequency of potentially actionable mutations in neuroblastoma, both at diagnosis and after chemotherapy. We performed a retrospective study to determine mutation frequency, the only inclusion criterion being availability of cancer gene panel sequencing data from Foundation Medicine. We analyzed 151 neuroblastoma tumor samples: 44 obtained at diagnosis, 42 at second look surgery or biopsy for stable disease after chemotherapy, and 59 at relapse (6 were obtained at unknown time points). Nine patients had multiple tumor biopsies. ALK was the most commonly mutated gene in this cohort, and we observed a higher frequency of suspected oncogenic ALK mutations in relapsed disease than at diagnosis. Patients with relapsed disease had, on average, a greater number of mutations reported to be recurrent in cancer, and a greater number of mutations in genes that are potentially targetable with available therapeutics. We also observed an enrichment of reported recurrent RAS/MAPK pathway mutations in tumors obtained after chemotherapy. Our data support recent evidence suggesting that neuroblastomas undergo substantial mutational evolution during therapy, and that relapsed disease is more likely to be driven by a targetable oncogenic pathway, highlighting that it is critical to base treatment decisions on the molecular profile of the tumor at the time of treatment. However, it will be necessary to conduct prospective clinical trials that match sequencing results to targeted therapeutic intervention to determine if cancer genomic profiling improves patient outcomes.
Irinotecan–temozolomide with temsirolimus or dinutuximab in children with refractory or relapsed neuroblastoma (COG ANBL1221): an open-label, randomised, phase 2 trial
Outcomes for children with relapsed and refractory neuroblastoma are dismal. The combination of irinotecan and temozolomide has activity in these patients, and its acceptable toxicity profile makes it an excellent backbone for study of new agents. We aimed to test the addition of temsirolimus or dinutuximab to irinotecan–temozolomide in patients with relapsed or refractory neuroblastoma. For this open-label, randomised, phase 2 selection design trial of the Children's Oncology Group (COG; ANBL1221), patients had to have histological verification of neuroblastoma or ganglioneuroblastoma at diagnosis or have tumour cells in bone marrow with increased urinary catecholamine concentrations at diagnosis. Patients of any age were eligible at first designation of relapse or progression, or first designation of refractory disease, provided organ function requirements were met. Patients previously treated for refractory or relapsed disease were ineligible. Computer-based randomisation with sequence generation defined by permuted block randomisation (block size two) was used to randomly assign patients (1:1) to irinotecan and temozolomide plus either temsirolimus or dinutuximab, stratified by disease category, previous exposure to anti-GD2 antibody therapy, and tumour MYCN amplification status. Patients in both groups received oral temozolomide (100 mg/m2 per dose) and intravenous irinotecan (50 mg/m2 per dose) on days 1–5 of 21-day cycles. Patients in the temsirolimus group also received intravenous temsirolimus (35 mg/m2 per dose) on days 1 and 8, whereas those in the dinutuximab group received intravenous dinutuximab (17·5 mg/m2 per day or 25 mg/m2 per day) on days 2–5 plus granulocyte macrophage colony-stimulating factor (250 μg/m2 per dose) subcutaneously on days 6–12. Patients were given up to a maximum of 17 cycles of treatment. The primary endpoint was the proportion of patients achieving an objective (complete or partial) response by central review after six cycles of treatment, analysed by intention to treat. Patients, families, and those administering treatment were aware of group assignment. This study is registered with ClinicalTrials.gov, number NCT01767194, and follow-up of the initial cohort is ongoing. Between Feb 22, 2013, and March 23, 2015, 36 patients from 27 COG member institutions were enrolled on this groupwide study. One patient was ineligible (alanine aminotransferase concentration was above the required range). Of the remaining 35 patients, 18 were randomly assigned to irinotecan–temozolomide–temsirolimus and 17 to irinotecan–temozolomide–dinutuximab. Median follow-up was 1·26 years (IQR 0·68–1·61) among all eligible participants. Of the 18 patients assigned to irinotecan–temozolomide–temsirolimus, one patient (6%; 95% CI 0·0–16·1) achieved a partial response. Of the 17 patients assigned to irinotecan–temozolomide–dinutuximab, nine (53%; 95% CI 29·2–76·7) had objective responses, including four partial responses and five complete responses. The most common grade 3 or worse adverse events in the temsirolimus group were neutropenia (eight [44%] of 18 patients), anaemia (six [33%]), thrombocytopenia (five [28%]), increased alanine aminotransferase (five [28%]), and hypokalaemia (four [22%]). One of the 17 patients assigned to the dinutuximab group refused treatment after randomisation; the most common grade 3 or worse adverse events in the remaining 16 patients evaluable for safety were pain (seven [44%] of 16), hypokalaemia (six [38%]), neutropenia (four [25%]), thrombocytopenia (four [25%]), anaemia (four [25%]), fever and infection (four [25%]), and hypoxia (four [25%]); one patient had grade 4 hypoxia related to therapy that met protocol-defined criteria for unacceptable toxicity. No deaths attributed to protocol therapy occurred. Irinotecan–temozolomide–dinutuximab met protocol-defined criteria for selection as the combination meriting further study whereas irinotecan–temozolomide–temsirolimus did not. Irinotecan–temozolomide–dinutuximab shows notable anti-tumour activity in patients with relapsed or refractory neuroblastoma. Further evaluation of biomarkers in a larger cohort of patients might identify those most likely to respond to this chemoimmunotherapeutic regimen. National Cancer Institute.
Pan-neuroblastoma analysis reveals age- and signature-associated driver alterations
Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. To better understand neuroblastoma pathogenesis, here we analyze whole-genome, whole-exome and/or transcriptome data from 702 neuroblastoma samples. Forty percent of samples harbor at least one recurrent driver gene alteration and most aberrations, including MYCN , ATRX , and TERT alterations, differ in frequency by age. MYCN alterations occur at median 2.3 years of age, TERT at 3.8 years, and ATRX at 5.6 years. COSMIC mutational signature 18, previously associated with reactive oxygen species, is the most common cause of driver point mutations in neuroblastoma, including most ALK and Ras-activating variants. Signature 18 appears early and is continuous throughout disease evolution. Signature 18 is enriched in neuroblastomas with MYCN amplification, 17q gain, and increased expression of mitochondrial ribosome and electron transport-associated genes. Recurrent FGFR1 variants in six patients, and ALK N-terminal structural alterations in five samples, identify additional patients potentially amenable to precision therapy. Genomic analysis of neuroblastoma has revealed important disease etiology. In this study, the authors assembled whole genome, exome and transcriptome data from over 700 neuroblastomas and identified molecular signatures correlated with age, and rare, potentially targetable variants overlooked in smaller cohorts.
Neuroblastoma
Neuroblastoma is the most common extracranial solid tumour occurring in childhood and has a diverse clinical presentation and course depending on the tumour biology. Unique features of these neuroendocrine tumours are the early age of onset, the high frequency of metastatic disease at diagnosis and the tendency for spontaneous regression of tumours in infancy. The most malignant tumours have amplification of the MYCN oncogene (encoding a transcription factor), which is usually associated with poor survival, even in localized disease. Although transgenic mouse models have shown that MYCN overexpression can be a tumour-initiating factor, many other cooperating genes and tumour suppressor genes are still under investigation and might also have a role in tumour development. Segmental chromosome alterations are frequent in neuroblastoma and are associated with worse outcome. The rare familial neuroblastomas are usually associated with germline mutations in ALK , which is mutated in 10–15% of primary tumours, and provides a potential therapeutic target. Risk-stratified therapy has facilitated the reduction of therapy for children with low-risk and intermediate-risk disease. Advances in therapy for patients with high-risk disease include intensive induction chemotherapy and myeloablative chemotherapy, followed by the treatment of minimal residual disease using differentiation therapy and immunotherapy; these have improved 5-year overall survival to 50%. Currently, new approaches targeting the noradrenaline transporter, genetic pathways and the tumour microenvironment hold promise for further improvements in survival and long-term quality of life. Neuroblastoma is a neuroendocrine tumour that arises in the developing sympathetic nervous system and is the most common malignancy diagnosed in the first year of life. This Primer by Matthay et al . reviews the mechanisms, diagnosis and risk-stratified management of neuroblastoma.
Neuroblastoma
The clinical hallmark of neuroblastoma is heterogeneity, with the likelihood of cure varying widely according to age at diagnosis, extent of disease, and tumour biology. A subset of tumours will undergo spontaneous regression while others show relentless progression. Around half of all cases are currently classified as high-risk for disease relapse, with overall survival rates less than 40% despite intensive multimodal therapy. This Seminar focuses on recent advances in our understanding of the biology of this complex paediatric solid tumour. We outline plans for the development of a uniform International Neuroblastoma Risk Group (INRG) classification system, and summarise strategies for risk-based therapies. We also update readers on new discoveries related to the underlying molecular pathogenesis of this tumour, with special emphasis on advances that are translatable to the clinic. Finally, we discuss new approaches to treatment, including recently discovered molecular targets that might provide more effective treatment strategies with the potential for less toxicity.
11q deletion in neuroblastoma: a review of biological and clinical implications
Deletion of the long arm of chromosome 11 (11q deletion) is one of the most frequent events that occur during the development of aggressive neuroblastoma. Clinically, 11q deletion is associated with higher disease stage and decreased survival probability. During the last 25 years, extensive efforts have been invested to identify the precise frequency of 11q aberrations in neuroblastoma, the recurrently involved genes, and to understand the molecular mechanisms of 11q deletion, but definitive answers are still unclear. In this review, it is our intent to compile and review the evidence acquired to date on 11q deletion in neuroblastoma.
Safety and activity of crizotinib for paediatric patients with refractory solid tumours or anaplastic large-cell lymphoma: a Children's Oncology Group phase 1 consortium study
Various human cancers have ALK gene translocations, amplifications, or oncogenic mutations, such as anaplastic large-cell lymphoma, inflammatory myofibroblastic tumours, non-small-cell lung cancer (NSCLC), and neuroblastoma. Therefore, ALK inhibition could be a useful therapeutic strategy in children. We aimed to determine the safety, recommended phase 2 dose, and antitumour activity of crizotinib in children with refractory solid tumours and anaplastic large-cell lymphoma. In this open-label, phase 1 dose-escalation trial, patients older than 12 months and younger than 22 years with measurable or evaluable solid or CNS tumours, or anaplastic large-cell lymphoma, refractory to therapy and for whom there was no known curative treatment were eligible. Crizotinib was given twice daily without interruption. Six dose levels (100, 130, 165, 215, 280, 365 mg/m2 per dose) were assessed in the dose-finding phase of the study (part A1), which is now completed. The primary endpoint was to estimate the maximum tolerated dose, to define the toxic effects of crizotinib, and to characterise the pharmacokinetics of crizotinib in children with refractory cancer. Additionally, patients with confirmed ALK translocations, mutations, or amplification (part A2 of the study) or neuroblastoma (part A3) could enrol at one dose level lower than was currently given in part A1. We assessed ALK genomic status in tumour tissue and used quantitative RT-PCR to measure NPM-ALK fusion transcript in bone marrow and blood samples of patients with anaplastic large-cell lymphoma. All patients who received at least one dose of crizotinib were evaluable for response; patients completing at least one cycle of therapy or experiencing dose limiting toxicity before that were considered fully evaluable for toxicity. This study is registered with ClinicalTrials.gov, NCT00939770. 79 patients were enrolled in the study from Oct 2, 2009, to May 31, 2012. The median age was 10·1 years (range 1·1–21·4); 43 patients were included in the dose escalation phase (A1), 25 patients in part A2, and 11 patients in part A3. Crizotinib was well tolerated with a recommended phase 2 dose of 280 mg/m2 twice daily. Grade 4 adverse events in cycle 1 were neutropenia (two) and liver enzyme elevation (one). Grade 3 adverse events that occurred in more than one patient in cycle 1 were lymphopenia (two), and neutropenia (eight). The mean steady state peak concentration of crizotinib was 630 ng/mL and the time to reach this peak was 4 h (range 1–6). Objective tumour responses were documented in 14 of 79 patients (nine complete responses, five partial responses); and the anti-tumour activity was enriched in patients with known activating ALK aberrations (eight of nine with anaplastic large-cell lymphoma, one of 11 with neuroblastoma, three of seven with inflammatory myofibroblastic tumour, and one of two with NSCLC). The findings suggest that a targeted inhibitor of ALK has antitumour activity in childhood malignancies harbouring ALK translocations, particularly anaplastic large-cell lymphoma and inflammatory myofibroblastic tumours, and that further investigation in the subset of neuroblastoma harbouring known ALK oncogenic mutations is warranted. Pfizer and National Cancer Institute grant to the Children's Oncology Group.
Recent Advances in Neuroblastoma
Neuroblastoma, an embryonal cancer of the autonomic nervous system, is the most common cancer diagnosed during the first year of life. Although neuroblastoma accounts for disproportionately high morbidity and mortality among childhood cancers, it has one of the highest rates of spontaneous and complete regression. The author discusses recent advances in our understanding of neuroblastoma. Neuroblastoma, an embryonal cancer of the autonomic nervous system, is the most common cancer diagnosed during the first year of life. The author discusses recent advances in our understanding of neuroblastoma. Neuroblastoma is an embryonal tumor of the autonomic nervous system, meaning that the cell of origin is thought to be a developing and incompletely committed precursor cell derived from neural-crest tissues. 1 As may be expected with a disease of developing tissues, neuroblastomas generally occur in very young children; the median age at diagnosis is 17 months. 2 The tumors arise in tissues of the sympathetic nervous system, typically in the adrenal medulla or paraspinal ganglia, and thus can present as mass lesions in the neck, chest, abdomen, or pelvis. The clinical presentation is highly variable, ranging from a mass that causes . . .
Genetic predisposition to neuroblastoma mediated by a LMO1 super-enhancer polymorphism
A causal variant is identified at the LMO1 oncogene locus that drives the genetic association of LMO1 with neuroblastoma susceptibility; the causal SNP disrupts a GATA transcription factor binding site within a tissue-specific super-enhancer element in the first intron of LMO1 , thereby affecting LMO1 expression. LMO1 oncogene involvement in neuroblastoma Polymorphisms at the oncogene LMO1 locus have previously been identified as being highly associated with susceptibility to neuroblastoma, a paediatric cancer. John Maris and colleagues now identify a causal variant at this locus, driving the LMO1 genetic association with neuroblastoma susceptibility. The authors show that the causal single nucleotide polymorphism disrupts a GATA transcription factor binding site in a tissue-specific super-enhancer element within the first intron of LMO1 , thereby affecting expression of the LMO1 oncogene. 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 1 . 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.
Circulating tumor DNA reveals mechanisms of lorlatinib resistance in patients with relapsed/refractory ALK-driven neuroblastoma
Activating point mutations in Anaplastic Lymphoma Kinase (ALK ) have positioned ALK as the only mutated oncogene tractable for targeted therapy in neuroblastoma. Cells with these mutations respond to lorlatinib in pre-clinical studies, providing the rationale for a first-in-child Phase 1 trial (NCT03107988) in patients with ALK-driven neuroblastoma. To track evolutionary dynamics and heterogeneity of tumors, and to detect early emergence of lorlatinib resistance, we collected serial circulating tumor DNA samples from patients enrolled on this trial. Here we report the discovery of off-target resistance mutations in 11 patients (27%), predominantly in the RAS-MAPK pathway. We also identify newly acquired secondary compound ALK mutations in 6 (15%) patients, all acquired at disease progression. Functional cellular and biochemical assays and computational studies elucidate lorlatinib resistance mechanisms. Our results establish the clinical utility of serial circulating tumor DNA sampling to track response and progression and to discover acquired resistance mechanisms that can be leveraged to develop therapeutic strategies to overcome lorlatinib resistance. Inhibition of ALK is initially effective in patients with ALK-driven lung cancer but resistance often arises. Here, the authors use circulating tumour DNA, collected as part of a phase I trial investigating lorlatinib (ALK inhibitor) in pediatric patients with ALK-driven neuroblastoma, to detect early resistance mechanisms.