Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Can Oncol Nurs J ; 34(2): 179-186, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706646

RESUMEN

Background: Approximately 82% of children with childhood cancer survive more than five years after diagnosis. Living as a cancer survivor elicits a new reality that can include psychosocial impacts. These psychosocial impacts interact collectively, especially regarding reassimilation, and are rarely explored. Objective: To explore the psychosocial impacts of surviving childhood cancer and reassimilation back into society in young adult survivors of childhood cancer. Methodology: Individual in-depth semi-structured interviews were conducted with childhood cancer survivors and explored psychosocial aspects associated with returning to work, school, and social environments after remission. Interpretive phenomenological analysis was conducted once interviews were manually transcribed. A group interview with survivors was held to discuss the study's findings and interpretation. Results: Individual interviews and the group interview revealed three major themes: outlook on reassimilating, outlook on coping, and outlook on cancer. Conclusions: This work is a first step to understanding how survivors' personal outlook on coping and healthcare system barriers play influential roles in reassimilation following cancer treatment. Survivors expressed the need for reliable survivorship information and improved communication with healthcare providers regarding what to expect, so they could feel prepared for life post-cancer. These aspects need to be explored more deeply through other qualitative studies.

2.
Can Assoc Radiol J ; 73(1): 187-193, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33998827

RESUMEN

PURPOSE: MRI is commonly used in follow up of high grade glioma. Our purpose is to assess the interrater agreement on the increasingly used visual qualitative assessment of various conventional and advanced MR techniques in the setting of treated high grade glioma in comparison to the well established quantitative measurements. METHODS: We prospectively enrolled HGG patients who underwent reresection of a new enhancing lesion on post-treatment 3T MR examination including DWI, DCE and DSC sequences. Two neuroradiologists objectively assessed the diffusion and perfusion maps by placing ROI on representative post-processed maps. They subjectively assessed the post-contrast, perfusion and diffusion sequences. Interrater agreement and concordance correlation coefficient were calculated. RESULTS: Twenty-eight lesions were included. The interrater agreement on the qualitative assessment was good for k-trans (k = 0.73), moderate for Vp (k = 0.52), fair for AUC and Ve maps (k = 0.37 and 0.21), fair for corrected CBV (k = 0.39) and poor for the enhancement pattern and presence of diffusion restriction (k = 0.02 and 0.07). The concordance between the quantitative measurements was substantial for AUC and Vp (ρc = 0.98 and 0.97), moderate for k-trans and corrected CBV (ρc = 0.94) and poor for Ve and ADC (ρc = 0.86 and 0.24). CONCLUSION: While the quantitative measurements of DSC and DCE perfusion maps show satisfactory inter-rater agreement, the qualitative assessment has lower interobserver agreement and should not be relied upon solely in the interpretation. Similarly, the suboptimal inter-rater agreement on the interpretation of enhancement pattern and diffusion restriction potentially limits their usefulness in differentiating glioma recurrence from treatment related changes.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/terapia , Glioma/diagnóstico por imagen , Glioma/terapia , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/cirugía , Quimioradioterapia/métodos , Diagnóstico Diferencial , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Prospectivos
3.
J Magn Reson Imaging ; 53(2): 416-426, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32940938

RESUMEN

BACKGROUND: The edited magnetic resonance spectroscopy (MRS) technique has not yet been formally evaluated for the in vivo detection of 2-hydroxyglutarate (2-HG) in patients with gliomas of various grades. PURPOSE: To evaluate the diagnostic accuracy of edited MRS in the preoperative identification of the isocitrate dehydrogenase (IDH) mutation status in patients with gliomas. STUDY TYPE: Prospective. POPULATION: Fifty-eight subjects (31 glioblastomas, 27 grade II and III gliomas). FIELD STRENGTH/SEQUENCE: Mescher-Garwood (MEGA)-PRESS and routine clinical brain tumor MR sequences were used at 3T. ASSESSMENT: Data were analyzed using an advanced method for accurate, robust, and efficient spectral fitting (AMARES) from jMRUI software. The amplitudes of the 2-HG, N-acetyl-aspartate (NAA), choline (Cho), and creatine/phosphocreatine (Cr) resonances were calculated with their associated Cramer-Rao lower bound (CRLB). The IDH1 R132H mutation status was assessed by immunohistochemistry for all patients. Patients with grades II and III gliomas with negative immunohistochemistry underwent DNA sequencing to further interrogate IDH mutation status. STATISTICAL TEST: The differences in 2-HG amplitudes, 2-HG/NAA, 2-HG/Cho, and 2-HG/Cr between IDH-mutant and IDH-wildtype gliomas were assessed using Mann-Whitney U-tests. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic accuracy of each parameter. RESULTS: The 2-HG amplitudes, 2-HG/NAA, and 2-HG/Cho were higher for IDH-mutant gliomas than IDH-wildtype gliomas (P < 0.007). Using a CRLB threshold <30%, a 2-HG cutoff greater than 0 had a sensitivity of 80% (95% confidence interval [CI]: 52-96%) and a specificity of 81% (95% CI: 54-96%) in identifying IDH-mutant gliomas. In the subset of patients with grades II and III gliomas, the sensitivity was 80% (95% CI: 52-96%) and specificity was 100% (95% CI: 40-100%). Among 2-HG ratios, the highest AUC for the identification of IDH mutant status was achieved using the 2-HG/NAA (AUC = 0.8, 95% CI 0.67-.89). DATA CONCLUSION: Preoperative edited MRS appears to be able to help identify IDH-mutant gliomas with high specificity. Level of Evidence 1 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:416-426.


Asunto(s)
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Glioma/diagnóstico por imagen , Glioma/genética , Humanos , Isocitrato Deshidrogenasa/genética , Mutación , Estudios Prospectivos
4.
J Magn Reson Imaging ; 50(2): 573-582, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30614146

RESUMEN

BACKGROUND: The appearance of a new enhancing lesion after surgery and chemoradiation for high-grade glioma (HGG) presents a common diagnostic dilemma. Histopathological analysis remains the reference standard in this situation. PURPOSE: To prospectively compare the diagnostic accuracy of dynamic contrast-enhanced (DCE) vs. dynamic susceptibility contrast (DSC) in differentiating tumor recurrence (TR) from radiation necrosis (RN). STUDY TYPE: Prospective diagnostic accuracy study. POPULATION: In all, 98 consecutive treated HGG patients with new enhancing lesion. We excluded 32 patients due to inadequate follow-up or technical limitation. FIELD STRENGTH/SEQUENCE: 3 T DCE and DSC MR. ASSESSMENT: Histogram and hot-spot analysis of cerebral blood volume (CBV), corrected CBV, Ktrans , area under the curve (AUC), and plasma volume (Vp). The reference standard of TR and/or RN was determined by histopathology in 43 surgically resected lesions or by clinical/imaging follow-up in the rest. STATISTICAL TESTS: Mann-Whitney U-tests, receiver operating characteristic (ROC) curve, and logistic regression analysis. RESULTS: A total of 68 lesions were included. There were 37 TR, 28 RN, and three lesions with equal proportions of TR and RN. TR had significantly higher CBV, corrected CBV, CBV ratio, corrected CBV ratio, AUC ratio, and Vp ratio (P < 0.05) than RN on hot-spot analysis. CBV had the highest diagnostic accuracy (AUROC 0.71). On histogram analysis, TR had higher CBV and corrected CBV maximal value compared with RN (P = 0.006, AUROC = 0.70). Only CBV on hot-spot analysis remained significant after correction for multiple comparison, with no significant improvement in diagnostic accuracy when using a combination of parameters (AUROC 0.71 vs. 0.76, P = 0.24). DATA CONCLUSION: DSC-derived CBV is the most accurate perfusion parameter in differentiating TR and RN. DSC and DCE-derived parameters reflecting the blood volume in an enhancing lesion are more accurate than the DCE-derived parameter Ktrans . Clinical practice may be best guided by blood volume measurements, rather than permeability assessment for differentiation of TR from RN. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 4 J. Magn. Reson. Imaging 2019;50:573-582.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Medios de Contraste , Glioma/diagnóstico por imagen , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Traumatismos por Radiación/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Necrosis/diagnóstico por imagen , Necrosis/etiología , Estudios Prospectivos , Reproducibilidad de los Resultados
6.
Can J Neurol Sci ; 45(2): 214-220, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29239294

RESUMEN

BACKGROUND: Neurosurgical residents face a unique combination of challenges, including long duty hours, technically challenging cases, and uncertain employment prospects. We sought to assess the demographics, interests, career goals, self-rated happiness, and overall well-being of Canadian neurosurgery residents. METHODS: A cross-sectional survey was developed and sent through the Canadian Neurosurgery Research Collaborative to every resident enrolled in a Canadian neurosurgery program as of April 1, 2016. RESULTS: We analyzed 76 completed surveys of 146 eligible residents (52% response rate). The median age was 29 years, with 76% of respondents being males. The most popular subspecialties of interest for fellowship were spine, oncology, and open vascular neurosurgery. The most frequent self-reported number of worked hours per week was the 80- to 89-hour range. The majority of respondents reported a high level of happiness as well as stress. Sense of accomplishment and fatigue were reported as average to high and overall quality of life was low for 19%, average for 49%, and high for 32%. Satisfaction with work-life balance was average for 44% of respondents and was the only tested domain in which significant dissatisfaction was identified (18%). Overall, respondents were highly satisfied with their choice of specialty, choice of program, surgical exposure, and work environment; however, intimidation was reported in 36% of respondents and depression by 17%. CONCLUSIONS: Despite a challenging residency and high workload, the majority of Canadian neurosurgery residents are happy and satisfied with their choice of specialty and program. However, work-life balance, employability, resident intimidation, and depression were identified as areas of active concern.


Asunto(s)
Selección de Profesión , Internado y Residencia/estadística & datos numéricos , Neurocirugia/educación , Neurocirugia/psicología , Calidad de Vida/psicología , Adulto , Canadá/epidemiología , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Admisión y Programación de Personal , Autoinforme , Carga de Trabajo/psicología , Adulto Joven
7.
Can J Neurol Sci ; 44(4): 415-419, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28322180

RESUMEN

Background Currently, the literature lacks reliable data regarding operative case volumes at Canadian neurosurgery residency programs. Our objective was to provide a snapshot of the operative landscape in Canadian neurosurgical training using the trainee-led Canadian Neurosurgery Research Collaborative. METHODS: Anonymized administrative operative data were gathered from each neurosurgery residency program from January 1, 2014, to December 31, 2014. Procedures were broadly classified into cranial, spine, peripheral nerve, and miscellaneous procedures. A number of prespecified subspecialty procedures were recorded. We defined the resident case index as the ratio of the total number of operations to the total number of neurosurgery residents in that program. Resident number included both Canadian medical and international medical graduates, and included residents on the neurosurgery service, off-service, or on leave for research or other personal reasons. RESULTS: Overall, there was an average of 1845 operative cases per neurosurgery residency program. The mean numbers of cranial, spine, peripheral nerve, and miscellaneous procedures were 725, 466, 48, and 193, respectively. The nationwide mean resident case indices for cranial, spine, peripheral nerve, and total procedures were 90, 58, 5, and 196, respectively. There was some variation in the resident case indices for specific subspecialty procedures, with some training programs not performing carotid endarterectomy or endoscopic transsphenoidal procedures. CONCLUSIONS: This study presents the breadth of neurosurgical training within Canadian neurosurgery residency programs. These results may help inform the implementation of neurosurgery training as the Royal College of Physicians and Surgeons residency training transitions to a competence-by-design curriculum.


Asunto(s)
Curriculum , Internado y Residencia , Neurocirugia/educación , Procedimientos Neuroquirúrgicos , Canadá , Femenino , Humanos , Masculino , Procedimientos Neuroquirúrgicos/educación , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Neuroquirúrgicos/estadística & datos numéricos
8.
Pediatr Blood Cancer ; 63(6): 983-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26871763

RESUMEN

Acute neurological changes in sickle cell disease (SCD) patients often raise the suspicion for stroke. Posterior reversible encephalopathy syndrome (PRES) can mimic stroke in its clinical presentation. We aimed to (i) review the PRES literature in SCD patients including clinical presentation, risk factors, pathophysiology, and management and (ii) elucidate the distinction between PRES and stroke in SCD. The exact pathophysiology of PRES in SCD remains elusive but is likely multifactorial and related to sickling, ischemia, and chronic anemia predisposing to vasogenic edema. PRES and stroke in SCD are distinguishable conditions. Our review may help elucidate a clinical approach to this distinction.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Síndrome de Leucoencefalopatía Posterior/diagnóstico , Síndrome de Leucoencefalopatía Posterior/etiología , Diagnóstico Diferencial , Humanos , Accidente Cerebrovascular/diagnóstico
9.
Implement Sci ; 19(1): 19, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395903

RESUMEN

BACKGROUND: Childhood cancer treatment while often curative, leads to elevated risks of morbidity and mortality. Survivors require lifelong periodic surveillance for late effects of treatment, yet adherence to guideline-recommended tests is suboptimal. We created ONLOOP to provide adult survivors of childhood cancer with detailed health information, including summaries of their childhood cancer treatment and recommended surveillance tests for early detection of cardiomyopathy, breast cancer, and/or colorectal cancer, with personalized reminders over time. METHODS: This is an individually randomized, registry-based pragmatic trial with an embedded process and economic evaluation to understand ONLOOP's impact and whether it can be readily implemented at scale. All adult survivors of childhood cancer in Ontario overdue for guideline-recommended tests will be randomly assigned to one of two arms: (1) intervention or (2) delayed intervention. A letter of information and invitation will detail the ONLOOP program. Those who sign up will receive a personalized toolkit and a screening reminder 6 months later. With the participants' consent, ONLOOP will also send their primary care clinician a letter detailing the recommended tests and a reminder 6 months later. The primary outcome will be the proportion of survivors who complete one or more of the guideline-recommended cardiac, breast, or colon surveillance tests during the 12 months after randomization. Data will be obtained from administrative databases. The intent-to-treat principle will be followed. Based on our analyses of administrative data, we anticipate allocating at least 862 individuals to each trial arm, providing 90% power to detect an absolute increase of 6% in targeted surveillance tests completed. We will interview childhood cancer survivors and family physicians in an embedded process evaluation to examine why and how ONLOOP achieved success or failed. A cost-effectiveness evaluation will be performed. DISCUSSION: The results of this study will determine if ONLOOP is effective at helping adult survivors of childhood cancer complete their recommended surveillance tests. This study will also inform ongoing provincial programs for this high-risk population. TRIAL REGISTRATION: ClinicalTrials.gov NCT05832138.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Adulto , Humanos , Niño , Femenino , Ontario , Detección Precoz del Cáncer , Sobrevivientes , Neoplasias de la Mama/diagnóstico , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Res Involv Engagem ; 9(1): 86, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37775825

RESUMEN

BACKGROUND: As research teams, networks, and institutes, and health, medical, and scientific communities begin to build consensus on the benefits of patient engagement in cancer research, research funders are increasingly looking to meaningfully incorporate patient partnership within funding processes and research requirements. The Canadian Cancer Society (CCS), the largest non-profit cancer research funder in Canada, set out to co-create a patient engagement in cancer research strategy with patients, survivors, caregivers and researchers. The goal of this strategy was to meaningfully and systematically engage with patients in research funding and research activities. METHODS: A team of four patient partners with diverse cancer and personal experiences, and two researchers at different career stages agreed to participate as members of the strategy team. Ten staff members participated in supportive roles and to give context regarding different departments of CCS. The strategy was co-developed in 2021/2022 over a series of 7 workshops using facilitation strategies such as ground rules and consensus building, and methods such as Design Thinking. The strategy was subjected to 3 rounds of validation. RESULTS: The co-creation and validation process resulted in a multi-faceted strategy with actionable sections, including vision, guiding principles, engagement methods, 13 prioritized engagement activities spanning the spectrum of research funding, and an evaluation framework. The experience of co-creating the strategy was captured using the Patient and Public Engagement Evaluation Tool and revealed a positive, supportive experience. CONCLUSIONS: Lessons learned included the value of an emphasis on a co-creation process from day one, the utility of facilitation techniques such as ground rules for dialogue, consensus building and Design Thinking, and the importance (and challenge) of designing for and incorporating equity when drafting the strategy. Future work will include implementation and evaluation of the strategy, as well as an examination of further ways to meaningfully and systematically engage diverse voices in research and research funding.


As researchers and healthcare providers see benefits of patient engagement in cancer research, research funders are also looking to engage with patients in their funding processes and research activities. The Canadian Cancer Society (CCS), the largest non-profit cancer research funder in Canada, set out to co-create a patient engagement in cancer research strategy with patients, survivors, caregivers and researchers. The goal of this strategy was to meaningfully and systematically engage with patients in research funding and research activities. Four patient partners and two researchers were supported by ten CCS staff members to co-create the strategy in 2021/2022 over a series of 7 workshops. They used facilitation strategies such as ground rules and consensus building, and methods such as Design Thinking. The strategy was then validated. Co-creation resulted in an easy-to-use strategy with actionable sections, including vision, guiding principles, engagement methods, 13 prioritized activities, and an evaluation framework. The experience of co-creating the strategy was captured using a well-regarded evaluation tool and revealed a positive, supportive experience.    Lessons learned during the process included making sure the co-creation process started on day one, the usefulness of facilitating the process, and the importance of considering issues of equity when drafting the strategy.

13.
Chin Neurosurg J ; 7(1): 6, 2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33423692

RESUMEN

Diffuse intrinsic pontine glioma (DIPG) is a lethal pediatric brain tumor and the leading cause of brain tumor-related death in children. As several clinical trials over the past few decades have led to no significant improvements in outcome, the current standard of care remains fractionated focal radiation. Due to the recent increase in stereotactic biopsies, tumor tissue availabilities have enabled our advancement of the genomic and molecular characterization of this lethal cancer. Several groups have identified key histone gene mutations, genetic drivers, and methylation changes in DIPG, providing us with new insights into DIPG tumorigenesis. Subsequently, there has been increased development of in vitro and in vivo models of DIPG which have the capacity to unveil novel therapies and strategies for drug delivery. This review outlines the clinical characteristics, genetic landscape, models, and current treatments and hopes to shed light on novel therapeutic avenues and challenges that remain.

14.
Neuro Oncol ; 23(5): 718-731, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33378446

RESUMEN

For decades, cell biologists and cancer researchers have taken advantage of non-murine species to increase our understanding of the molecular processes that drive normal cell and tissue development, and when perturbed, cause cancer. The advent of whole-genome sequencing has revealed the high genetic homology of these organisms to humans. Seminal studies in non-murine organisms such as Drosophila melanogaster, Caenorhabditis elegans, and Danio rerio identified many of the signaling pathways involved in cancer. Studies in these organisms offer distinct advantages over mammalian cell or murine systems. Compared to murine models, these three species have shorter lifespans, are less resource intense, and are amenable to high-throughput drug and RNA interference screening to test a myriad of promising drugs against novel targets. In this review, we introduce species-specific breeding strategies, highlight the advantages of modeling brain tumors in each non-mammalian species, and underscore the successes attributed to scientific investigation using these models. We conclude with an optimistic proposal that discoveries in the fields of cancer research, and in particular neuro-oncology, may be expedited using these powerful screening tools and strategies.


Asunto(s)
Neoplasias Encefálicas , Pez Cebra , Animales , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Caenorhabditis elegans , Drosophila melanogaster , Humanos , Ratones , Transducción de Señal
15.
World Neurosurg ; 111: e465-e470, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29277596

RESUMEN

BACKGROUND: Smartphones and their apps are used ubiquitously in medical practice. However, in some cases their use can be at odds with current patient data safety regulations such as Canada's Personal Health Information Protection Act of 2004. To assess current practices and inform mobile application development, we sought to better understand mobile device usage patterns among Canadian neurosurgery residents. METHODS: Through the Canadian Neurosurgery Research Collaborative, an online survey characterizing smartphone ownership and usage patterns was developed and sent to all Canadian neurosurgery resident in April of 2016. Questionnaires were collected and completed surveys analyzed. RESULTS: Of 146 eligible residents, 76 returned completed surveys (52% response rate). Of these 99% of respondents owned a smartphone, with 79% running on Apple's iOS. Four general mobile uses were identified: 1) communication between members of the medical team, 2) decision support, 3) medical reference, and 4) documentation through medical photography. Communication and photography were areas where the most obvious breaches in the Canadian Personal Health Information Protection Act were noted, with 89% of respondents taking pictures of patients' radiologic studies and 75% exchanging them with Short Message System. Hospital policies had no impact on user behaviors. CONCLUSIONS: Smartphones are used daily by most neurosurgery residents. Identified usage patterns are associated with perceived gains in efficacy and challenges in privacy and data reliability. We believe creating and improving workflows that address these usage patterns has a greater potential to improve privacy than changing policies and enforcing regulations.


Asunto(s)
Neurocirujanos/estadística & datos numéricos , Teléfono Inteligente/estadística & datos numéricos , Canadá , Estudios Transversales , Femenino , Humanos , Internado y Residencia , Masculino , Neurocirugia , Encuestas y Cuestionarios
17.
Oncotarget ; 7(43): 69518-69535, 2016 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-27588472

RESUMEN

First-line cancer therapies such as alkylating agents and radiation have limited survival benefits for Glioblastoma (GBM) patients. Current research strongly supports the notion that inhibition of aberrant tumor metabolism holds promise as a therapeutic strategy when used in combination with radiation and chemotherapy. Hexokinase 2 (HK2) has been shown to be a key driver of altered metabolism in GBM, and presents an attractive therapeutic target. To date, no study has fully assessed the therapeutic value of targeting HK2 as a mechanism to sensitize cells to standard therapy, namely in the form of radiation and temozolomide (TMZ). Using cell lines and primary cultures of GBM, we showed that inducible knockdown of HK2 altered tumor metabolism, which could not be recapitulated by HK1 or HK3 loss. HK2 loss diminished both in vivo tumor vasculature as well as growth within orthotopic intracranial xenograft models of GBMs, and the survival benefit was additive with radiation and TMZ. Radio-sensitization following inhibition of HK2 was mediated by increased DNA damage, and could be rescued through constitutive activation of ERK signaling. This study supports HK2 as a potentially effective therapeutic target in GBM.


Asunto(s)
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Hexoquinasa/genética , Interferencia de ARN , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Antineoplásicos Alquilantes/farmacología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Quimioradioterapia , Daño del ADN , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Glioblastoma/metabolismo , Glioblastoma/patología , Células HEK293 , Hexoquinasa/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de la radiación , Masculino , Ratones Endogámicos NOD , Ratones SCID , Temozolomida
18.
Cancer Res ; 76(16): 4708-19, 2016 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-27325644

RESUMEN

Proliferating cancer cells are characterized by high rates of glycolysis, lactate production, and altered mitochondrial metabolism. This metabolic reprogramming provides important metabolites for proliferation of tumor cells, including glioblastoma. These biological processes, however, generate oxidative stress that must be balanced through detoxification of reactive oxygen species (ROS). Using an unbiased retroviral loss-of-function screen in nontransformed human astrocytes, we demonstrate that mitochondrial PTEN-induced kinase 1 (PINK1) is a regulator of the Warburg effect and negative regulator of glioblastoma growth. We report that loss of PINK1 contributes to the Warburg effect through ROS-dependent stabilization of hypoxia-inducible factor-1A and reduced pyruvate kinase muscle isozyme 2 activity, both key regulators of aerobic glycolysis. Mechanistically, PINK1 suppresses ROS and tumor growth through FOXO3a, a master regulator of oxidative stress and superoxide dismutase 2. These findings highlight the importance of PINK1 and ROS balance in normal and tumor cells. PINK1 loss was observed in a significant number of human brain tumors including glioblastoma (n > 900) and correlated with poor patient survival. PINK1 overexpression attenuates in vivo glioblastoma growth in orthotopic mouse xenograft models and a transgenic glioblastoma model in Drosophila Cancer Res; 76(16); 4708-19. ©2016 AACR.


Asunto(s)
Neoplasias Encefálicas/patología , Glioblastoma/patología , Proteínas Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Astrocitos/metabolismo , Western Blotting , Proliferación Celular , Drosophila , Glucólisis/fisiología , Xenoinjertos , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos NOD , Ratones SCID , Estrés Oxidativo/fisiología
19.
Cancer Res ; 69(19): 7548-56, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19773446

RESUMEN

Glioblastoma multiforme (GBM) is the most common and most malignant adult brain tumor. A characteristic of GBM is their highly invasive nature, making complete surgical resection impossible. The most common gain-of-function alteration in GBM is amplification, overexpression, and mutations of the epidermal growth factor receptor (EGFR). The constitutively activated mutant EGFR variant III (EGFRvIII), found in approximately 20% of GBM, confers proliferative and invasive advantage. The signaling cascades downstream of aberrant EGFR activation contributing to the invasive phenotype are not completely understood. Here, we show myristoylated alanine-rich protein kinase C substrate (MARCKS), previously implicated in cell adhesion and motility, contributes to EGFR-mediated invasion of human GBM cells. EGFRvIII-expressing or EGF-stimulated human GBM cells increased expression, phosphorylation, and cytosolic translocation of MARCKS in a protein kinase C-alpha-dependent manner. Down-regulation of MARCKS expression with small interfering RNA in GBM cells expressing EGFRvIII led to decreased cell adhesion, spreading, and invasion. Elucidation of mechanisms that promote EGFRvIII-mediated tumorigenesis in GBM, such as MARCKS, provides additional understanding and potential biological targets against this currently terminal human cancer.


Asunto(s)
Neoplasias Encefálicas/enzimología , Receptores ErbB/metabolismo , Glioblastoma/enzimología , Proteínas de la Membrana/biosíntesis , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Factor de Crecimiento Epidérmico/farmacología , Receptores ErbB/biosíntesis , Glioblastoma/genética , Glioblastoma/patología , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Sustrato de la Proteína Quinasa C Rico en Alanina Miristoilada , Invasividad Neoplásica , Proteína Quinasa C-alfa/metabolismo , ARN Interferente Pequeño/genética , Transducción de Señal , Transfección
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA