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1.
Br J Cancer ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834745

RESUMO

BACKGROUND: Diffuse invasion remains a primary cause of treatment failure in pediatric high-grade glioma (pHGG). Identifying cellular driver(s) of pHGG invasion is needed for anti-invasion therapies. METHODS: Ten highly invasive patient-derived orthotopic xenograft (PDOX) models of pHGG were subjected to isolation of matching pairs of invasive (HGGINV) and tumor core (HGGTC) cells. RESULTS: pHGGINV cells were intrinsically more invasive than their matching pHGGTC cells. CSC profiling revealed co-positivity of CD133 and CD57 and identified CD57+CD133- cells as the most abundant CSCs in the invasive front. In addition to discovering a new order of self-renewal capacities, i.e., CD57+CD133- > CD57+CD133+ > CD57-CD133+ > CD57-CD133- cells, we showed that CSC hierarchy was impacted by their spatial locations, and the highest self-renewal capacities were found in CD57+CD133- cells in the HGGINV front (HGGINV/CD57+CD133- cells) mediated by NANOG and SHH over-expression. Direct implantation of CD57+ (CD57+/CD133- and CD57+/CD133+) cells into mouse brains reconstituted diffusely invasion, while depleting CD57+ cells (i.e., CD57-CD133+) abrogated pHGG invasion. CONCLUSION: We revealed significantly increased invasive capacities in HGGINV cells, confirmed CD57 as a novel glioma stem cell marker, identified CD57+CD133- and CD57+CD133+ cells as a new cellular driver of pHGG invasion and suggested a new dual-mode hierarchy of HGG stem cells.

2.
J Transl Med ; 21(1): 444, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415222

RESUMO

BACKGROUND: Animal models representing different molecular subtypes of glioblastoma multiforme (GBM) is desired for developing new therapies. SVV-001 is an oncolytic virus selectively targeting cancer cells. It's capacity of passing through the blood brain barrier makes is an attractive novel approach for GBM. MATERIALS AND METHODS: 23 patient tumor samples were implanted into the brains of NOD/SCID mice (1 × 105 cells/mouse). Tumor histology, gene expression (RNAseq), and growth rate of the developed patient-derived orthotopic xenograft (PDOX) models were compared with the originating patient tumors during serial subtransplantations. Anti-tumor activities of SVV-001 were examined in vivo; and therapeutic efficacy validated in vivo via single i.v. injection (1 × 1011 viral particle) with or without fractionated (2 Gy/day x 5 days) radiation followed by analysis of animal survival times, viral infection, and DNA damage. RESULTS: PDOX formation was confirmed in 17/23 (73.9%) GBMs while maintaining key histopathological features and diffuse invasion of the patient tumors. Using differentially expressed genes, we subclassified PDOX models into proneural, classic and mesenchymal groups. Animal survival times were inversely correlated with the implanted tumor cells. SVV-001 was active in vitro by killing primary monolayer culture (4/13 models), 3D neurospheres (7/13 models) and glioma stem cells. In 2/2 models, SVV-001 infected PDOX cells in vivo without harming normal brain cells and significantly prolonged survival times in 2/2 models. When combined with radiation, SVV-001 enhanced DNA damages and further prolonged animal survival times. CONCLUSION: A panel of 17 clinically relevant and molecularly annotated PDOX modes of GBM is developed, and SVV-001 exhibited strong anti-tumor activities in vitro and in vivo.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Animais , Camundongos , Glioblastoma/radioterapia , Glioblastoma/metabolismo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Animais de Doenças , Linhagem Celular Tumoral
3.
J Neurooncol ; 165(2): 353-360, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945818

RESUMO

INTRODUCTION: Diffuse midline glioma (DMG) of the pons occurs in pediatric patients and carries a dismal prognosis. Biopsy is not necessary for diagnosis but provides information, particularly H3K27M status, with prognostic implications. Additionally, biopsy information may open therapeutic options such as clinical trials that require mutation status. Therefore, we sought to assess the safety of surgical biopsy in DMG patients as well as its potential impact on clinical course. METHODS: Retrospective analysis of patients who were radiographically and clinically diagnosed with pontine DMG in the last 5 years was performed. We assessed demographic, clinical, radiographic, surgical, and follow-up data. RESULTS: 25 patients were included; 18 (72%) underwent biopsy while 7 (28%) declined. 12 biopsies (67%) were performed with robotic arm and 5 (27%) with frameless stereotaxy. Three biopsied patients (17%) experienced new post-operative neurologic deficits (1 facial palsy, 1 VI nerve palsy and 1 ataxia) that all resolved at 2-week follow-up. All biopsies yielded diagnostic tissue. Fourteen patients (78%) had H3K27M mutation. Median OS for H3K27M patients was 10 months compared to 11 months in the wild-type patients (p = 0.30, log-rank test). Median OS for patients enrolled in clinical trials was 12 months compared to 8 months for non-trial patients (p = 0.076). CONCLUSION: In our series, stereotactic pontine DMG biopsies did not carry any permanent deficit or complication and yielded diagnostic tissue in all patients. Similar post-operative course was observed in both robot-assisted and frameless stereotactic approaches. There was no significant difference in survival based on mutation status or clinical trial enrollment.


Assuntos
Neoplasias Encefálicas , Glioma , Criança , Humanos , Biópsia , Neoplasias Encefálicas/patologia , Glioma/genética , Glioma/cirurgia , Glioma/diagnóstico , Mutação , Ponte/patologia , Ponte/cirurgia , Estudos Retrospectivos
4.
Lab Invest ; 102(2): 185-193, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34802040

RESUMO

Brain tumors are the leading cause of cancer-related death in children. Tazemetostat is an FDA-approved enhancer of zeste homolog (EZH2) inhibitor. To determine its role in difficult-to-treat pediatric brain tumors, we examined EZH2 levels in a panel of 22 PDOX models and confirmed EZH2 mRNA over-expression in 9 GBM (34.6 ± 12.7-fold) and 11 medulloblastoma models (6.2 ± 1.7 in group 3, 6.0 ± 2.4 in group 4) accompanied by elevated H3K27me3 expression. Therapeutic efficacy was evaluated in 4 models (1 GBM, 2 medulloblastomas and 1 ATRT) via systematically administered tazemetostat (250 and 400 mg/kg, gavaged, twice daily) alone and in combination with cisplatin (5 mg/kg, i.p., twice) and/or radiation (2 Gy/day × 5 days). Compared with the untreated controls, tazemetostat significantly (Pcorrected < 0.05) prolonged survival times in IC-L1115ATRT (101% at 400 mg/kg) and IC-2305GBM (32% at 250 mg/kg, 45% at 400 mg/kg) in a dose-dependent manner. The addition of tazemetostat with radiation was evaluated in 3 models, with only one [IC-1078MB (group 4)] showing a substantial, though not statistically significant, prolongation in survival compared to radiation treatment alone. Combining tazemetostat (250 mg/kg) with cisplatin was not superior to cisplatin alone in any model. Analysis of in vivo drug resistance detected predominance of EZH2-negative cells in the remnant PDOX tumors accompanied by decreased H3K27me2 and H3K27me3 expressions. These data supported the use of tazemetostat in a subset of pediatric brain tumors and suggests that EZH2-negative tumor cells may have caused therapy resistance and should be prioritized for the search of new therapeutic targets.


Assuntos
Neoplasias Encefálicas/terapia , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Adolescente , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzamidas/administração & dosagem , Benzamidas/farmacologia , Compostos de Bifenilo/administração & dosagem , Compostos de Bifenilo/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Quimiorradioterapia , Criança , Cisplatino/administração & dosagem , Terapia Combinada/métodos , Avaliação Pré-Clínica de Medicamentos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Inibidores Enzimáticos/administração & dosagem , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Lactente , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Morfolinas/administração & dosagem , Morfolinas/farmacologia , Piridonas/administração & dosagem , Piridonas/farmacologia , Dosagem Radioterapêutica
5.
Cancer ; 127(20): 3865-3871, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34254296

RESUMO

BACKGROUND: Both intensity-modulated radiotherapy (RT) and passively scattered proton therapy have a risk of secondary malignant neoplasm (SMN) in children. To determine the influence of RT modality on the incidence of SMN after craniospinal irradiation (CSI), the authors compared the incidence of SMN in children who had medulloblastoma treated with either photon CSI plus an intensity-modulated RT boost (group I) or passively scattered proton CSI plus a boost (group II). METHODS: From 1996 to 2014, 115 children with medulloblastoma (group I, n = 63; group II, n = 52) received CSI followed by a boost to the tumor bed. Most patients had standard-risk disease (63.5%). The median follow-up was 12.8 years for group I and 8.7 years for group II. RESULTS: The 5-year and 10-year overall survival (OS) rates were 88.8% and 85.1%, respectively, for standard-risk patients and 63.1% and 57.3%, respectively, for high-risk patients, with no OS difference by RT modality (P = .81). Six SMNs were identified (4 in group I, 2 in group II). The 5-year and 10-year SMN incidence rates were 1.0% and 6.9%, respectively (0.0% and 8.0%, respectively, in group I; 2.2% and 4.9%, respectively, in group II; P = .74). Two SMNs occurred in the clinical target volume in the brain, 2 occurred in the exit dose region from the photon spinal field, 1 occurred in the entrance path of a proton beam, and 1 occurred outside the radiation field. There were no reported cases of secondary leukemia. CONCLUSIONS: This analysis demonstrates no difference in OS or SMN incidence between patients in groups I and II 10 years after RT. LAY SUMMARY: One hundred fifteen children with medulloblastoma received radiotherapy (RT) with either photon craniospinal irradiation (CSI) and an intensity-modulated RT boost (group I; n = 63) or passively scattered proton CSI and a boost (group II;, n = 52). The majority of children had standard-risk disease (63.5%). The 5-year and 10-year overall survival rates were 88.8% and 85.1% for standard-risk patients, respectively, and 63.1% and 57.3% for high-risk patients, respectively, with no difference in overall survival by RT group (P = .81). The 5-year and 10-year second malignant neoplasm incidence rates were 1.0% and 6.9%, respectively, with no difference in second malignant neoplasm incidence according to RT group (P = .74).


Assuntos
Neoplasias Cerebelares , Radiação Cranioespinal , Meduloblastoma , Terapia com Prótons , Neoplasias Cerebelares/radioterapia , Criança , Radiação Cranioespinal/efeitos adversos , Humanos , Meduloblastoma/patologia , Meduloblastoma/radioterapia , Terapia com Prótons/efeitos adversos , Prótons , Dosagem Radioterapêutica
6.
Cancer ; 127(13): 2358-2367, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33739455

RESUMO

BACKGROUND: Sporadic optic pathway/hypothalamic gliomas represent a unique entity within pediatric low-grade glioma. Despite favorable survival, location makes treatment difficult and local progression debilitating. This study is a longitudinal assessment of visual acuity (VA) among children treated within the last 2 decades. METHODS: Clinical characteristics were abstracted for patients treated from 2000 to 2018 at Texas Children's Cancer Center in Houston. Ophthalmologic data taken at 3- to 6-month intervals were examined with age-appropriate VA metrics converted to the LogMAR (logarithm of the minimum angle of resolution) scale. Kaplan-Meier blindness-free survival (BFS) curves, calculated as time-to-bilateral functional blindness (LogMAR ≥0.8 in both eyes), were calculated for patients receiving early radiation therapy (RT; upfront or as first-line salvage treatment) or chemotherapy (CT) and evaluated using the log-rank test. RESULTS: Thirty-eight patients with a median follow-up of 8.5 years (range, 2-17 years) were identified. Median age at diagnosis was 3 years (interquartile range, <1-6 years). Early RT was administered in 11 patients (29%). Twenty-seven patients (71%) were treated primarily with CT, initiated at a median age of 3.5 years (range, <1-11 years). Eight patients in the CT group did eventually require RT secondary to VA loss and following multiple lines of CT. Median age at RT for all patients was 11 years (range, 3-17 years). BFS rates were 81% at 5 years and 60% at 8 years for CT and 100% at 5 and 8 years for early RT (P = .017). CONCLUSIONS: In a contemporary cohort, early RT, defined as initial or first-line salvage therapy, was found to have superior BFS for appropriately selected patients with sporadic optic pathway/hypothalamic gliomas. LAY SUMMARY: Children with low-grade brain tumors of the optic pathway generally have excellent long-term survival; however, given the location of these tumors, there can commonly be threatened vision if the tumor grows. Although radiation is generally deferred in children on the basis of legitimate concerns regarding the effects on the developing brain, it may represent a vision-preserving therapy for well-selected older patients.


Assuntos
Glioma do Nervo Óptico , Criança , Pré-Escolar , Seguimentos , Humanos , Lactente , Glioma do Nervo Óptico/complicações , Glioma do Nervo Óptico/tratamento farmacológico , Glioma do Nervo Óptico/radioterapia , Estudos Retrospectivos , Terapia de Salvação , Transtornos da Visão , Acuidade Visual
7.
Pediatr Blood Cancer ; 68(2): e28756, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33025730

RESUMO

BACKGROUND: Central nervous system (CNS) malignancies are the most common solid tumors among children, and novel therapies are needed to help improve survival. Pomalidomide is an immunomodulatory agent that displays antiangiogenic and cytotoxic activity, making it an appropriate candidate to explore in pediatric CNS tumors. METHODS: A phase 1 first in pediatric trial of pomalidomide was conducted in children with recurrent, progressive, and refractory CNS tumors. The primary objective was to determine the maximum tolerated dose (MTD) and/or recommended phase 2 dose (RP2D) when given orally once daily for 21 consecutive days of a 28-day cycle. Once the MTD was established, 12 additional patients were enrolled on expansion cohorts based on age and steroid use. RESULTS: Twenty-nine children were enrolled and 25 were evaluable for dose-limiting toxicity (DLT). The MTD was 2.6 mg/m2 (dose level 2). Four DLTs were observed in three patients at dose level 3 (3.4 mg/m2 ) includeding grade 3 diarrhea, grade 3 thrombocytopenia, grade 3 lung infection, and grade 4 neutropenia. The most common adverse events were grade 1 and 2 myelosuppression. One patient with an oligodendroglioma had stable disease for nine cycles, and a second patient with an anaplastic pleomorphic xanthoastrocytoma achieved a sustained partial response. Immunologic analyses suggested that pomalidomide triggers immunomodulation. CONCLUSIONS: The MTD of pomalidomide is 2.6 mg/m2 . It was well tolerated, and immune correlates showed a serum immune response. These data led to an industry-sponsored phase 2 trial of pomalidomide monotherapy in children with recurrent brain tumors (NCT03257631).


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Talidomida/análogos & derivados , Adolescente , Inibidores da Angiogênese/farmacocinética , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Feminino , Humanos , Imunomodulação/efeitos dos fármacos , Masculino , Talidomida/farmacocinética , Talidomida/uso terapêutico , Adulto Jovem
8.
Pediatr Blood Cancer ; 68(4): e28879, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33405376

RESUMO

BACKGROUND: Disruption of cell-cycle regulators is a potential therapeutic target for brain tumors in children and adolescents. The aim of this study was to determine the maximum tolerated dose (MTD) and describe toxicities related to palbociclib, a selective cyclin-dependent kinase 4/6 (CDK4/6) inhibitor in pediatric patients with progressive/refractory brain tumors with intact retinoblastoma protein. METHODS: Palbociclib was administered orally starting at 50 mg/m2 daily for the first 21 days of a 28-day course. Dose escalation was according to the Rolling-6 statistical design in less heavily (stratum I) and heavily pretreated (stratum II) patients, and MTD was determined separately for each group. Pharmacokinetic studies were performed during the first course, and pharmacodynamic studies were conducted to evaluate relationships between drug levels and toxicities. RESULTS: A total of 21 patients were enrolled on stratum I and 14 patients on stratum II. The MTD for both strata was 75 mg/m2 . Palbociclib absorption (mean Tmax between 4.9 and 6.6 h) and elimination (mean half-life between 11.3 and 19.5 h) were assessed. The most common toxicity was myelosuppression. Higher palbociclib exposure was associated with grade 3/4 neutropenia and leukopenia. Dose limiting toxicities included grade 4 neutropenia and grade 3 thrombocytopenia and dehydration. No patients had an objective response to palbociclib therapy. CONCLUSIONS: Palbociclib was safely administered to children and adolescents at a dosage of 75 mg/m2 for 21 consecutive days followed by seven days of rest in both strata. Future studies will establish its optimal utilization in pediatric patients with brain tumors.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Adolescente , Adulto , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Progressão da Doença , Feminino , Humanos , Masculino , Piperazinas/efeitos adversos , Piperazinas/farmacocinética , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Piridinas/efeitos adversos , Piridinas/farmacocinética , Adulto Jovem
9.
Pediatr Blood Cancer ; 68(10): e29178, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133064

RESUMO

BACKGROUND: Patients with chiasmatic-hypothalamic low-grade glioma (CHLGG) have frequent MRIs with gadolinium-based contrast agents (GBCA) for disease monitoring. Cumulative gadolinium deposition in the brains of children is a potential concern. The purpose of this study is to evaluate whether MRI with GBCA is necessary for determining radiographic tumor progression in children with CHLGG. METHODS: Children who were treated for progressive CHLGG from 2005 to 2019 at Texas Children's Cancer Center were identified. Pre- and post-contrast MRI sequences were separately reviewed by one neuroradiologist who was blinded to the clinical course. Three dimensional measurements and tumor characteristics were evaluated. Radiographic progression was defined as a 25% increase in size (product of two largest dimensions) compared with baseline or best response after initiation of therapy. RESULTS: A total of 28 patients with progressive CHLGG were identified with a total of 683 MRIs with GBCA reviewed (mean 24 MRIs/patient; range, 11-43 MRIs). Radiographic progression was observed 92 times, 91 (99%) on noncontrast and 90 (98%) on contrast imaging. Sixty-seven progressions necessitating management changes were identified in all (100%) noncontrast sequences and 66 (99%) contrast sequences. Tumor growth > 2 mm in any dimension was identified in 184/187 (98%) noncontrast and 181/187 (97%) with contrast imaging. Metastatic tumors were better visualized on contrast imaging in 4/7 (57%). CONCLUSION: MRI without GBCA effectively identifies patients with progressive disease. When imaging children with CHLGG, eliminating GBCA should be considered unless monitoring patients with metastatic disease.


Assuntos
Gadolínio , Glioma , Encéfalo/diagnóstico por imagem , Criança , Meios de Contraste , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
10.
Lancet Oncol ; 21(6): e330-e336, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32502459

RESUMO

Optimising the conduct of clinical trials for diffuse intrinsic pontine glioma involves use of consistent, objective disease assessments and standardised response criteria. The Response Assessment in Pediatric Neuro-Oncology working group, consisting of an international panel of paediatric and adult neuro-oncologists, clinicians, radiologists, radiation oncologists, and neurosurgeons, was established to address issues and unique challenges in assessing response in children with CNS tumours. A working group was formed specifically to address response assessment in children and young adults with diffuse intrinsic pontine glioma and to develop a consensus on recommendations for response assessment. Response should be assessed using MRI of brain and spine, neurological examination, and anti-inflammatory or antiangiogenic drugs. Clinical imaging standards are defined. As with previous consensus recommendations, these recommendations will need to be validated in prospective clinical trials.


Assuntos
Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/terapia , Glioma Pontino Intrínseco Difuso/diagnóstico por imagem , Glioma Pontino Intrínseco Difuso/terapia , Determinação de Ponto Final/normas , Imageamento por Ressonância Magnética/normas , Neuroimagem/normas , Idade de Início , Neoplasias do Tronco Encefálico/epidemiologia , Neoplasias do Tronco Encefálico/patologia , Glioma Pontino Intrínseco Difuso/epidemiologia , Glioma Pontino Intrínseco Difuso/patologia , Humanos , Gradação de Tumores , Valor Preditivo dos Testes , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral
11.
Pediatr Blood Cancer ; 67(6): e28283, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32285998

RESUMO

PURPOSE: To study the efficacy and tolerability of valproic acid (VPA) and radiation, followed by VPA and bevacizumab in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) or high-grade glioma (HGG). METHODS: Children 3 to 21 years of age received radiation therapy and VPA at 15 mg/kg/day and dose adjusted to maintain a trough range of 85 to 115 µg/mL. VPA was continued post-radiation, and bevacizumab was started at 10 mg/kg intravenously biweekly, four weeks after completing radiation therapy. RESULTS: From September 2009 through August 2015, 20 DIPG and 18 HGG patients were enrolled (NCT00879437). During radiation and VPA, grade 3 or higher toxicities requiring discontinuation or modification of VPA dosing included grade 3 thrombocytopenia (1), grade 3 weight gain (1), and grade 3 pancreatitis (1). During VPA and bevacizumab, the most common grade 3 or higher toxicities were grade 3 neutropenia (3), grade 3 thrombocytopenia (3), grade 3 fatigue (3), and grade 3 hypertension (4). Two patients discontinued protocol therapy prior to disease progression (one grade 4 thrombosis and one grade 1 intratumoral hemorrhage). Median event-free survival (EFS) and overall survival (OS) for DIPG were 7.8 (95% CI 5.6-8.2) and 10.3 (7.4-13.4) months, and estimated one-year EFS was 12% (2%-31%). Median EFS and OS for HGG were 9.1 (6.4-11) and 12.1 (10-22.1) months, and estimated one-year EFS was 24% (7%-45%). Four patients with glioblastoma and mismatch-repair deficiency syndrome had EFS of 28.5, 16.7, 10.4, and 9 months. CONCLUSION: Addition of VPA and bevacizumab to radiation was well tolerated but did not appear to improve EFS or OS in children with DIPG or HGG.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Tronco Encefálico/terapia , Quimiorradioterapia/mortalidade , Glioma Pontino Intrínseco Difuso/terapia , Adolescente , Adulto , Bevacizumab/administração & dosagem , Neoplasias do Tronco Encefálico/patologia , Criança , Pré-Escolar , Glioma Pontino Intrínseco Difuso/patologia , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Taxa de Sobrevida , Ácido Valproico/administração & dosagem , Adulto Jovem
12.
Lancet Oncol ; 20(7): 1011-1022, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31151904

RESUMO

BACKGROUND: Paediatric low-grade glioma is the most common CNS tumour of childhood. Although overall survival is good, disease often recurs. No single universally accepted treatment exists for these patients; however, standard cytotoxic chemotherapies are generally used. We aimed to assess the activity of selumetinib, a MEK1/2 inhibitor, in these patients. METHODS: The Pediatric Brain Tumor Consortium performed a multicentre, phase 2 study in patients with paediatric low-grade glioma in 11 hospitals in the USA. Patients aged 3-21 years with a Lansky or Karnofsky performance score greater than 60 and the presence of recurrent, refractory, or progressive paediatric low-grade glioma after at least one standard therapy were eligible for inclusion. Patients were assigned to six unique strata according to histology, tumour location, NF1 status, and BRAF aberration status; herein, we report the results of strata 1 and 3. Stratum 1 comprised patients with WHO grade I pilocytic astrocytoma harbouring either one of the two most common BRAF aberrations (KIAA1549-BRAF fusion or the BRAFV600E [Val600Glu] mutation). Stratum 3 comprised patients with any neurofibromatosis type 1 (NF1)-associated paediatric low-grade glioma (WHO grades I and II). Selumetinib was provided as capsules given orally at the recommended phase 2 dose of 25 mg/m2 twice daily in 28-day courses for up to 26 courses. The primary endpoint was the proportion of patients with a stratum-specific objective response (partial response or complete response), as assessed by the local site and sustained for at least 8 weeks. All responses were reviewed centrally. All eligible patients who initiated treatment were evaluable for the activity and toxicity analyses. Although the trial is ongoing in other strata, enrolment and planned follow-up is complete for strata 1 and 3. This trial is registered with ClinicalTrials.gov, number NCT01089101. FINDINGS: Between July 25, 2013, and June 12, 2015, 25 eligible and evaluable patients were accrued to stratum 1, and between Aug 28, 2013, and June 25, 2015, 25 eligible and evaluable patients were accrued to stratum 3. In stratum 1, nine (36% [95% CI 18-57]) of 25 patients achieved a sustained partial response. The median follow-up for the 11 patients who had not had a progression event by Aug 9, 2018, was 36·40 months (IQR 21·72-45·59). In stratum 3, ten (40% [21-61]) of 25 patients achieved a sustained partial response; median follow-up was 48·60 months (IQR 39·14-51·31) for the 17 patients without a progression event by Aug 9, 2018. The most frequent grade 3 or worse adverse events were elevated creatine phosphokinase (five [10%]) and maculopapular rash (five [10%]). No treatment-realted deaths were reported. INTERPRETATION: Selumetinib is active in recurrent, refractory, or progressive pilocytic astrocytoma harbouring common BRAF aberrations and NF1-associated paediatric low-grade glioma. These results show that selumetinib could be an alternative to standard chemotherapy for these subgroups of patients, and have directly led to the development of two Children's Oncology Group phase 3 studies comparing standard chemotherapy to selumetinib in patients with newly diagnosed paediatric low-grade glioma both with and without NF1. FUNDING: National Cancer Institute Cancer Therapy Evaluation Program, the American Lebanese Syrian Associated Charities, and AstraZeneca.


Assuntos
Benzimidazóis/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Glioma/tratamento farmacológico , Adolescente , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Progressão da Doença , Feminino , Glioma/genética , Glioma/patologia , Humanos , Masculino , Gradação de Tumores , Neoplasias Primárias Múltiplas/patologia , Neurofibromatose 1/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Adulto Jovem
13.
Nurs Educ Perspect ; 40(1): 58-59, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29994885

RESUMO

Decreasing access to clinical sites, inconsistency in student learning experiences, and lack of faculty have compelled nursing schools to incorporate more simulation into their curricula. Professional organizations, regulating bodies, and schools of nursing support its use. The Nursing 2 Challenge simulation activity was designed to give second-semester nursing students an opportunity to improve skill competence and critical thinking utilizing a systematic, preplanned station rotation format in the safe setting of the nursing campus lab. Each station required the students to apply clinical decision-making and nursing skills to complete interventions aligned with course objectives.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Competência Clínica , Criatividade , Currículo , Humanos , Pensamento
14.
Pediatr Blood Cancer ; 65(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29090526

RESUMO

BACKGROUND: We conducted a phase II study of oral capecitabine rapidly disintegrating tablets given concurrently with radiation therapy (RT) to assess progression-free survival (PFS) in children with newly diagnosed diffuse intrinsic pontine gliomas (DIPG). PATIENTS AND METHODS: Children 3-17 years with newly diagnosed DIPG were eligible. Capecitabine, 650 mg/m2 /dose BID (maximum tolerated dose [MTD] in children with concurrent radiation), was administered for 9 weeks starting the first day of RT. Following a 2-week break, three courses of capecitabine, 1,250 mg/m2 /dose BID for 14 days followed by a 7-day rest, were administered. As prospectively designed, 10 evaluable patients treated at the MTD on the phase I trial were included in the phase II analyses. The design was based on comparison of the PFS distribution to a contemporary historical control (n = 140) with 90% power to detect a 15% absolute improvement in the 1-year PFS with a type-1 error rate, α = 0.10. RESULTS: Forty-four patients were evaluable for the phase II objectives. Capecitabine and RT was well tolerated with low-grade palmar plantar erythrodyesthesia, increased alanine aminotransferase, cytopenias, and vomiting the most commonly reported toxicities. Findings were significant for earlier progression with 1-year PFS of 7.21% (SE = 3.47%) in the capecitabine-treated cohort versus 15.59% (SE = 3.05%) in the historical control (P = 0.007), but there was no difference for overall survival (OS) distributions (P = 0.30). Tumor enhancement at diagnosis was associated with shorter PFS and OS. Capecitabine was rapidly absorbed and converted to its metabolites. CONCLUSION: Capecitabine did not improve the outcome for children with newly diagnosed DIPG.


Assuntos
Neoplasias do Tronco Encefálico/terapia , Capecitabina/administração & dosagem , Quimiorradioterapia , Glioma/terapia , Administração Oral , Adolescente , Neoplasias do Tronco Encefálico/diagnóstico , Criança , Pré-Escolar , Feminino , Seguimentos , Glioma/diagnóstico , Humanos , Masculino , Estudos Prospectivos , Comprimidos
15.
Nurs Educ Perspect ; 39(4): 250-252, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29863548

RESUMO

The use of electronic data management systems is rapidly expanding. Nurses need to be competent in the use of electronic health records (EHRs) and understand their contribution to safe, effective, high quality patient care. Faculty must incorporate learning experiences in the application of EHRs into undergraduate nursing programs in order to adequately prepare students for employment. This article reports the challenges involved in the successful addition of an academic EHR into an existing curriculum.


Assuntos
Currículo , Registros Eletrônicos de Saúde , Humanos
16.
Cancer Immunol Immunother ; 66(12): 1589-1595, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28825123

RESUMO

BACKGROUND: We evaluated circulating levels of immunosuppressive regulatory T cells (Tregs) and other lymphocyte subsets in patients with newly diagnosed medulloblastoma (MBL) undergoing surgery compared to a control cohort of patients undergo craniectomy for correction of Chiari malformation (CM) and further determined the impact of standard irradiation and chemotherapy on this cell population. METHODS: Eligibility criteria for this biologic study included age 4-21 years, patients with CM undergoing craniectomy (as non-malignant surgical controls) and receiving dexamethasone for prevention of post-operative nausea, and those with newly diagnosed posterior fossa tumors (PFT) undergoing surgical resection and receiving dexamethasone as an anti-edema measure. Patients with confirmed MBL were also followed for longitudinal blood collection and analysis during radiotherapy and chemotherapy. RESULTS: A total of 54 subjects were enrolled on the study [22-CM, 18-MBL, and 14-PFT]. Absolute number and percentage Tregs (defined as CD4+CD25+FoxP3+CD127low/-) at baseline were decreased in MBL and PFT compared to CM [p = 0.0016 and 0.001, respectively). Patients with MBL and PFT had significantly reduced overall CD4+ T cell count (p = 0.0014 and 0.0054, respectively) compared to those with CM. Radiation and chemotherapy treatment in patients with MBL reduced overall lymphocyte counts; however, within the CD4+ T cell compartment, Tregs increased during treatment but gradually declined post therapy. CONCLUSIONS: Our results demonstrate that patients with MBL and PFT exhibit overall reduced CD4+ T cell counts at diagnosis but not an elevated proportion of Tregs. Standard treatment exacerbates lymphopenia in those with MBL while enriching for immunosuppressive Tregs over time.


Assuntos
Neoplasias Cerebelares/imunologia , Neoplasias Cerebelares/terapia , Meduloblastoma/imunologia , Meduloblastoma/terapia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Neoplasias Cerebelares/sangue , Quimiorradioterapia , Criança , Pré-Escolar , Craniotomia , Feminino , Humanos , Masculino , Meduloblastoma/sangue , Adulto Jovem
17.
J Neurooncol ; 128(1): 47-56, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26956263

RESUMO

Metastatic intracranial germinoma is difficult to treat. Although the proto-oncogene KIT is recognized as one of the most frequent genetic abnormalities in CNS germinoma, the development of new target therapeutic agents for CNS germinoma is hampered by the lack of clinically-relevant animal models that replicate the mutated or over-expressed KIT. CNS germinoma tumor cells from five pediatric patients were directly implanted into the brains of Rag2/severe combined immune deficiency mice. Once established, the xenograft tumors were sub-transplanted in vivo in mouse brains. Characterization of xenograft tumors were performed through histologic and immunohistochemical staining, and KIT mutation analysed with quantitative pyro-sequencing. Expression of putative cancer stem cell markers (CD133, CD15, CD24, CD44, CD49f) was analyzed through flow cytometry. Two patient-derived orthotopic xenograft (PDOX) models (IC-6999GCT and IC-9302GCT) were established from metastatic germinoma and serially sub-transplanted five times in mouse brains. Similar to the original patient tumors, they both exhibited faint expression (+) of PLAP, no expression (-) of ß-HCG and strong (+++) expression of KIT. KIT mutation (D816H), however, was only found in IC-9320GCT. This mutation was maintained during the five in vivo tumor passages with an increased mutant allele frequency compared to the patient tumor. Expression of putative cancer stem cell markers CD49f and CD15 was also detected in a small population of tumor cells in both models. This new pair of PDOX models replicated the key biological features of pediatric intracranial germinoma and should facilitate the biological and pre-clinical studies for metastatic intracranial germinomas.


Assuntos
Neoplasias Encefálicas/genética , Germinoma/genética , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-kit/genética , Adolescente , Animais , Biomarcadores Tumorais/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Criança , Feminino , Germinoma/metabolismo , Germinoma/patologia , Xenoenxertos , Humanos , Imuno-Histoquímica , Lactente , Masculino , Camundongos SCID , Metástase Neoplásica , Células-Tronco Neoplásicas , Proto-Oncogene Mas , Análise de Sequência de DNA , Análise de Sobrevida
18.
Can Assoc Radiol J ; 67(1): 88-95, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26608253

RESUMO

In 2013 Health Canada conducted a national survey of computed tomography (CT) radiation usage. We analysed contributions from all 7 public health authorities in the province of British Columbia, which covered scanner age, number of slices, and common adult protocols (≥ 19 years: 70 ± 20 kg, head, chest, abdomen/pelvis, and trunk). Patient doses were recorded for common protocols. Diagnostic reference levels (DRLs) was calculated using scanner data with >10 patient doses recorded for each protocol. Data was analysed based on image reconstruction (filtered backprojection vs iterative reconstruction [IR] vs IR available but not in use). Provincial response was 92%, with 59 of 64 CT data used for analysis. The average scanner age was 5.5 years old, with 39% of scanners installed between 2008-2013; 78.5% of scanners were multislice (>64 slices), and 44% of scanners had IR available. Overall British Columbia DRLs were: head = 1305, chest = 529, abdomen/pelvis = 819, and trunk = 1225. DRLs were consistent with Health Canada recommendations and other Canadian published values, but above international standards. For sites with IR available, less than 50% used this technology routinely for head, chest and trunk exams. Overall, use of IR reduced radiation usage between 11%-32% compared to filtered backprojection, while sites using IR vs IR available used 30%/43% less radiation for head/chest exams (P < .05). No significant difference was observed for abdomen/pelvis exams (P = .385). With the fast pace of CT technical advancement, DRLs should reflect the technology used, instead of just globally applied to anatomical regions. Federal guidelines should be updated at a higher frequency to reflect new technology. In addition, new technologies must be utilised to optimize image quality vs radiation usage.


Assuntos
Doses de Radiação , Tomografia Computadorizada por Raios X , Adulto , Colúmbia Britânica , Humanos , Inquéritos e Questionários , Tomografia Computadorizada por Raios X/instrumentação
19.
J Appl Clin Med Phys ; 16(5): 159­166, 2015 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-26699296

RESUMO

Permanent implant of sealed radioactive sources is an effective technique for treating cancer. Typically, the radioactive sources are implanted in and near the disease, depositing radiation absorbed dose locally over several months. There may be instances where these patients must undergo unrelated surgical procedures when the radioactive material remains active enough to pose risks. This work explores these risks, discusses strategies to mitigate those risks, and describes a case study for a permanent iodine-125 (I-125) prostate brachytherapy implant patient who developed colorectal cancer and required surgery six months after brachytherapy. The first consideration is identifying the radiological risk to the patient and staff before, during, and after the surgical procedure. The second is identifying the risk the surgical procedure may have on the efficacy of the brachytherapy implant. Finally, there are considerations for controlling the radioactive substances from a regulatory perspective. After these risks are defined, strategies to mitigate those risks are considered. We summarize this experience with some guidelines: If the surgical procedure is near (e.g., within 5-10 cm of) the implant; and, the surgical intervention may dislodge sources enough to compromise treatment or introduces radiation safety risks; and, the radioactivity has not sufficiently decayed to background levels; and, the surgery cannot be postponed, then a detailed analysis of risk is advised.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Corpo Clínico , Prostatectomia , Neoplasias da Próstata/radioterapia , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação , Proteção Radiológica/métodos , Braquiterapia , Humanos , Masculino , Prognóstico , Neoplasias da Próstata/cirurgia , Próteses e Implantes , Radiometria , Dosagem Radioterapêutica
20.
Transl Oncol ; 45: 101988, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733642

RESUMO

Radiation is one of the standard therapies for pediatric high-grade glioma (pHGG), of which the prognosis remains poor. To gain an in-depth understanding of biological consequences beyond the classic DNA damage, we treated 9 patient-derived orthotopic xenograft (PDOX) models, including one with DNA mismatch repair (MMR) deficiency, with fractionated radiations (2 Gy/day x 5 days). Extension of survival time was noted in 5 PDOX models (P < 0.05) accompanied by γH2AX positivity in >95 % tumor cells in tumor core and >85 % in the invasive foci as well as ∼30 % apoptotic and mitotic catastrophic cell death. The model with DNA MMR (IC-1406HGG) was the most responsive to radiation with a reduction of Ki-67(+) cells. Altered metabolism, including mitochondria number elevation, COX IV activation and reactive oxygen species accumulation, were detected together with the enrichment of CD133+ tumor cells. The latter was caused by the entry of quiescent G0 cells into cell cycle and the activation of self-renewal (SOX2 and BMI1) and epithelial mesenchymal transition (fibronectin) genes. These novel insights about the cellular and molecular mechanisms of fractionated radiation in vivo should support the development of new radio-sensitizing therapies.

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