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1.
BMC Cancer ; 22(1): 645, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35692047

RESUMO

BACKGROUND: Given the young age of patients with CNS WHO grade 2 and 3 oligodendrogliomas and the relevant risk of neurocognitive, functional, and quality-of-life impairment with the current aggressive standard of care treatment, chemoradiation with PCV, of the tumour located in the brain optimizing care is the major challenge. METHODS: NOA-18 aims at improving qualified overall survival (qOS) for adult patients with CNS WHO grade 2 and 3 oligodendrogliomas by randomizing between standard chemoradiation with up to six six-weekly cycles with PCV and six six-weekly cycles with lomustine and temozolomide (CETEG) (n = 182 patients per group accrued over 4 years) thereby delaying radiotherapy and adding the chemoradiotherapy concept at progression after initial radiation-free chemotherapy, allowing for effective salvage treatment and delaying potentially deleterious side effects. QOS represents a new concept and is defined as OS without functional and/or cognitive and/or quality of life deterioration regardless of whether tumour progression or toxicity is the main cause. The primary objective is to show superiority of an initial CETEG treatment followed by partial brain radiotherapy (RT) plus PCV (RT-PCV) at progression over partial brain radiotherapy (RT) followed by procarbazine, lomustine, and vincristine (PCV) chemotherapy (RT-PCV) and best investigators choice (BIC) at progression for sustained qOS. An event concerning a sustained qOS is then defined as a functional and/or cognitive and/or quality of life deterioration after completion of primary therapy on two consecutive study visits with an interval of 3 months, tolerating a deviation of at most 1 month. Assessments are done with a 3-monthly MRI, assessment of the NANO scale, HRQoL, and KPS, and annual cognitive testing. Secondary objectives are evaluation and comparison of the two groups regarding secondary endpoints (short-term qOS, PFS, OS, complete and partial response rate). The trial is planned to be conducted at a minimum of 18 NOA study sites in Germany. DISCUSSION: qOS represents a new concept. The present NOA trial aims at showing the superiority of CETEG plus RT-PCV over RT-PCV plus BIC as determined at the level of OS without sustained functional deterioration for all patients with oligodendroglioma diagnosed according to the most recent WHO classification. TRIAL REGISTRATION: Clinicaltrials.gov NCT05331521 . EudraCT 2018-005027-16.


Assuntos
Neoplasias Encefálicas , Oligodendroglioma , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Humanos , Lomustina/uso terapêutico , Gradação de Tumores , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/genética , Oligodendroglioma/patologia , Procarbazina/uso terapêutico , Qualidade de Vida , Resultado do Tratamento , Vincristina/uso terapêutico
2.
Eur J Neurol ; 28(1): 331-340, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918834

RESUMO

BACKGROUND AND PURPOSE: We quantified peripheral nerve lesions in adults with 5q-linked spinal muscular atrophy (SMA) type 3 by analysing the magnetization transfer ratio (MTR) of the sciatic nerve, and tested its potential as a novel biomarker for macromolecular changes. METHODS: Eighteen adults with SMA 3 (50% SMA 3a, 50% SMA 3b) and 18 age-/sex-matched healthy controls prospectively underwent magnetization transfer contrast imaging in a 3-Tesla magnetic resonance scanner. Two axial three-dimensional gradient echo sequences, with and without an off-resonance saturation rapid frequency pulse, were performed at the right distal thigh. Sciatic nerve regions of interest were manually traced on 10 consecutive axial slices in the images generated without off-resonance saturation, and then transferred to corresponding slices generated by the sequence with the off-resonance saturation pulse. Subsequently, MTR and cross-sectional areas (CSAs) of the sciatic nerve were analysed. In addition, detailed neurologic, physiotherapeutic and electrophysiologic examinations were conducted in all patients. RESULTS: Sciatic nerve MTR and CSA reliably differentiated between healthy controls and SMA 3, 3a or 3b. MTR was lower in the SMA 3 (P < 0.0001), SMA 3a (P < 0.0001) and SMA 3b groups (P = 0.0020) than in respective controls. In patients with SMA 3, MTR correlated with all clinical scores, and arm nerve compound motor action potentials (CMAPs). CSA was lower in the SMA 3 (P < 0.0001), SMA 3a (P < 0.0001) and SMA 3b groups (P = 0.0006) than in controls, but did not correlate with clinical scores or electrophysiologic results. CONCLUSIONS: Magnetization transfer ratio is a novel imaging marker that quantifies macromolecular nerve changes in SMA 3, and positively correlates with clinical scores and CMAPs.


Assuntos
Imageamento por Ressonância Magnética , Atrofia Muscular Espinal , Adulto , Biomarcadores , Humanos , Espectroscopia de Ressonância Magnética , Atrofia Muscular Espinal/diagnóstico por imagem , Nervos Periféricos
3.
Nervenarzt ; 92(10): 996-1001, 2021 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-34476518

RESUMO

Brain tumors represent a special interdisciplinary challenge in the treatment of neurological disorders. Insights into the interindividual as well as the spatial and temporal intraindividual heterogeneity require entirely new personalized treatment approaches. Particularly in the field of immunotherapy there are possibilities for targeted interventions and systematic follow-up for assessment of response to treatment. Although not yet integrated into the standard treatment, early clinical trials in recent years have shown the feasibility of systematic personalized treatment approaches. The conceptual and regulatory implications of these approaches reach far beyond the field of neuro-oncology.


Assuntos
Neoplasias Encefálicas , Encéfalo , Neoplasias Encefálicas/terapia , Humanos , Fatores Imunológicos , Imunoterapia
4.
Neuropathol Appl Neurobiol ; 46(5): 422-430, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31867747

RESUMO

AIMS: DNA methylation-based central nervous system (CNS) tumour classification has identified numerous molecularly distinct tumour types, and clinically relevant subgroups among known CNS tumour entities that were previously thought to represent homogeneous diseases. Our study aimed at characterizing a novel, molecularly defined variant of glioneuronal CNS tumour. PATIENTS AND METHODS: DNA methylation profiling was performed using the Infinium MethylationEPIC or 450 k BeadChip arrays (Illumina) and analysed using the 'conumee' package in R computing environment. Additional gene panel sequencing was also performed. Tumour samples were collected at the German Cancer Research Centre (DKFZ) and provided by multinational collaborators. Histological sections were also collected and independently reviewed. RESULTS: Genome-wide DNA methylation data from >25 000 CNS tumours were screened for clusters separated from established DNA methylation classes, revealing a novel group comprising 31 tumours, mainly found in paediatric patients. This DNA methylation-defined variant of low-grade CNS tumours with glioneuronal differentiation displays recurrent monosomy 14, nuclear clusters within a morphology that is otherwise reminiscent of oligodendroglioma and other established entities with clear cell histology, and a lack of genetic alterations commonly observed in other (paediatric) glioneuronal entities. CONCLUSIONS: DNA methylation-based tumour classification is an objective method of assessing tumour origins, which may aid in diagnosis, especially for atypical cases. With increasing sample size, methylation analysis allows for the identification of rare, putative new tumour entities, which are currently not recognized by the WHO classification. Our study revealed the existence of a DNA methylation-defined class of low-grade glioneuronal tumours with recurrent monosomy 14, oligodendroglioma-like features and nuclear clusters.


Assuntos
Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/patologia , Cromossomos Humanos Par 14/genética , Glioma/genética , Glioma/patologia , Metilação de DNA , Feminino , Humanos , Masculino , Monossomia , Neurocitoma/genética , Neurocitoma/patologia , Oligodendroglioma/genética , Oligodendroglioma/patologia
5.
Eur J Neurol ; 27(8): 1638-1646, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32337811

RESUMO

BACKGROUND AND PURPOSE: Although patient-centredness is considered a key component of high-quality neurological care, it is unclear to what extent it can or should be implemented during the acute phase. Using acute stroke as an example, the aim was to identify critical junctures for patient-centredness along the acute care pathway from the perspectives of patients, relatives and staff. METHODS: A qualitative multi-method study was conducted including 27 non-participant observations and 37 semi-structured interviews with patients, relatives and staff. Junctures were defined as critical when mentioned (as problematic) in two or three information sources (i.e. observations, staff interviews, or patient and relative interviews), as potentially critical when mentioned in one, and as uncritical when not mentioned. RESULTS: Post-procedure communication after thrombectomy, patients' stay at the stroke unit and decision-making around transfer, discharge and rehabilitation were identified as critical junctures for patient-centredness. Arrival at the emergency department and the (thrombectomy) treatment itself were identified as uncritical junctures, whilst history-taking and treatment preparation, the treatment decision and patients' stay at the intensive care unit were identified as potentially critical junctures. CONCLUSIONS: In acute stroke care, patients, relatives and staff prioritize fast over patient-centred decision-making in the most time-critical phases, especially before and during treatment. This is reversed after the procedure, when difficulties arise implementing a patient-centred approach in clinical practice. To improve patient-centredness where it is most needed, clear guidelines and accessible resources are recommended. Future research should investigate whether insights from acute phases of stroke care are applicable to other neurological conditions as well.


Assuntos
Assistência Centrada no Paciente , Acidente Vascular Cerebral , Cuidados Críticos , Humanos , Pesquisa Qualitativa , Qualidade da Assistência à Saúde , Acidente Vascular Cerebral/terapia
6.
Neuropathol Appl Neurobiol ; 45(2): 108-118, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30326163

RESUMO

AIMS: Mutations of isocitrate dehydrogenase (IDH)1/2 affect almost all astrocytomas of WHO grade II and III. A subset of IDH-mutant astrocytic tumours progresses to IDH-mutant glioblastoma or presents with the histology of a glioblastoma at first presentation. We set out here to assess the molecular spectrum of IDH-mutant glioblastomas. METHODS: We performed an integrated molecular analysis of a mono-centric cohort (n = 97); assessed through genome-wide DNA methylation analysis, copy-number profiling and targeted next generation sequencing using a neurooncology-tailored gene panel. RESULTS: Of these 97 IDH-mutant glioblastomas, 68 had a glioblastoma at first presentation ('de novo' IDH-mutant glioblastoma) and 29 emerged from a prior low-grade lesion ('evolved' IDH-mutant glioblastoma). Unsupervised hierarchical clustering of DNA methylation data disclosed that IDH-mutant glioblastoma ('de novo' and 'evolved') formed a distinct group separate from other diffuse glioma subtypes. Homozygous deletions of CDKN2A/B were found to be associated with shorter survival. CONCLUSIONS: This study demonstrates DNA methylation patterns in IDH-mutant glioblastoma to be distinct from lower-grade astrocytic counterparts but homogeneous within de novo and evolved IDH-mutant glioblastomas, and identifies CDKN2A as a marker for possible genetic sub-stratification.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioma/patologia , Isocitrato Desidrogenase/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/genética , Neoplasias Encefálicas/genética , Glioma/genética , Humanos , Pessoa de Meia-Idade , Mutação/genética , Gradação de Tumores/métodos , Adulto Jovem
9.
Nervenarzt ; 86(6): 692, 694-6, 698-700, 2015 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-26022855

RESUMO

Current therapies for patients with malignant gliomas are starting to integrate molecular factors and age. Nonetheless, these therapies are still not sufficiently individualized. Some positive examples of transfer from basic science to clinical application are currently integrated into the standard treatment and guidelines. These are mainly genetic and other molecular factors that improve diagnosis and classification of gliomas and markers supporting prognostication. Examples for predictive biomarkers are methylation of the O-6-methylguanine-DNA methyltransferase (MGMT) promoter and the codeletion of chromosome arms 1p and 19q (1p/19q codel). The autoactive, truncated form of epidermal growth factor receptor (EGFRvIII) and the R132H mutation of isocitrate dehydrogenase 1 (IDH-1) are used as targets in currently running immunotherapeutic, targeted trials. Integration of functional imaging parameters into the monitoring and development of uniform assessment criteria improve the ability to evaluate therapy response and implement imaging biomarkers to guide therapies. As a result of the current efforts there are better classified prognostic groups and improved survival times with maintained functional and quality of life parameters in some glioma subgroups. Given the current dynamics, an improved, better differentiated classification of brain tumors including molecular parameters as well as more rational precise guiding of therapies with early, uniform response assessment is expected in the near future.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/genética , Glioma/terapia , Terapia de Alvo Molecular/métodos , Medicina de Precisão/métodos , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico , Testes Genéticos/métodos , Glioma/diagnóstico , Humanos , Técnicas de Diagnóstico Molecular/métodos
10.
J Neurooncol ; 117(1): 25-32, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24395351

RESUMO

There is a lack of relevant prognostic and predictive factors in neurooncology besides mutation of isocitrate dehydrogenase 1, codeletion of 1p/19q and promoter hypermethylation of O (6) -methylguanine-DNA-methyltransferase. More importantly, there is limited translation of these factors into clinical practice. The cancer genome atlas data and also clinical correlative analyses suggest a pivotal role for the epidermal growth factor receptor /protein kinase B/mammalian target of rapamycin (mTOR) pathway in both biology and the clinical course of gliomas. However, attempts to stratify gliomas by activating alterations in this pathway have failed thus far. The tumors of 40 patients with WHO grade II gliomas without immediate postoperative genotoxic treatment and known progression and survival status at a median follow-up of 12.2 years were analyzed for expression of the mTOR complex 2 downstream target N-myc downstream regulated gene (NDRG)1 using immunohistochemistry. Baseline characteristics for NDRG1 absent/low versus moderate/high patients were similar. Time to reintervention was significantly longer in the NDRG1 group (P = 0.026). NDRG1 may become a novel biomarker to guide the decision which WHO°II glioma patients may be followed without postsurgical intervention and which patients should receive genotoxic treatment early on. Validation of this hypothesis will be possible with the observational arm of the RTOG 9802 and the pretreatment step of the EORTC 22033/26032 trials.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Glioma/diagnóstico , Glioma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Adulto , Idoso , Astrocitoma/diagnóstico , Astrocitoma/metabolismo , Astrocitoma/patologia , Astrocitoma/terapia , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Seguimentos , Glioma/patologia , Glioma/terapia , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Gradação de Tumores , Oligodendroglioma/diagnóstico , Oligodendroglioma/metabolismo , Oligodendroglioma/patologia , Oligodendroglioma/terapia , Prognóstico , Estudos Prospectivos , Retratamento , Análise de Sobrevida , Fatores de Tempo
11.
Nervenarzt ; 84(8): 937-42, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23775285

RESUMO

The treatment of patients with intrinsic brain tumors is radically changing. This change is currently not (yet) signified by the use of targeted therapy in clinical practice but more by the definition of molecular markers as predictors for response to therapy which have been used for a long time. While in the past the choice of treatment has been based solely on the tumor entity and its degree of malignancy derived from histological analyses, large randomized trials have now provided a solid basis for personalized molecular-guided treatment decisions. For instance, in the German NOA-08 trial a benefit of chemotherapy with temozolomide alone was only demonstrated in a subgroup of elderly patients with malignant gliomas displaying promoter hypermethylation of the DNA repair enzyme MGMT. This is only one of several examples where molecular analysis of tumor tissue becomes clinically relevant as these analyses can and should be taken into account for treatment decisions and not, as previously, just as an additional parameter for estimating prognosis. This article illustrates the current developments in the area of personalized neurooncology and critically reviews the impact on clinical decision-making in daily practice.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Terapia Genética/métodos , Oncologia/métodos , Neurologia/métodos , Patologia Molecular/métodos , Medicina de Precisão/métodos , Neoplasias Encefálicas/genética , Marcação de Genes , Humanos
14.
Nervenarzt ; 83(8): 982-7, 2012 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-22801663

RESUMO

Despite considerable advancements in the therapy of malignant glioma in recent years with modern radiation and surgical techniques, alkylating and antiangiogenic chemotherapy, as well as molecular-based treatment decisions, treatment outcomes are mostly unsatisfactory. Understandably, patients often ask for experimental, sometimes unusual therapeutic modalities and this should be integrated into the clinical practice. In addition to experimental therapeutic approaches based on novel drugs, viral agents, immunotherapy and radiation approaches, experimental procedures of interest for patients particularly encompass mechanical approaches with the aim at physically altering the tumor tissue by temperature, oxygenation or magnetization. These mechanical procedures are based on intuitive concepts and promise fewer side effects than other experimental approaches. In addition, the requirements for approval by medical device regulations in terms of proof of efficacy are generally less stringent. As a consequence approaches, such as hyperbaric oxygenation, hyperthermia and electric fields, which are often heavily advertised and in part reimbursed by health insurances, have been used for many years, often by centers not specialized in the treatment of brain tumor patients, although sound data from prospective controlled clinical trials that determine which patients in which situation may benefit, are generally lacking. In this review we review these clinical therapeutic approaches.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/terapia , Terapia por Estimulação Elétrica/tendências , Oxigenoterapia Hiperbárica/tendências , Hipertermia Induzida/tendências , Nanocápsulas/uso terapêutico , Humanos
15.
Minim Invasive Neurosurg ; 54(5-6): 268-70, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22278794

RESUMO

BACKGROUND: Parenchymal hemorrhage is one of the most feared risks of stereotactic brain biopsies potentially resulting in neurological deficits or even a fatal outcome. Patients with disorders of the coagulation system are at particular risk, so identifying these is one of the main tasks prior to surgery. Some patients may have a bleeding tendency despite normal laboratory values of the hemostatic system. CASE REPORT: We report the case of a patient with coagulopathy of unclear etiology undergoing a stereotactic brainstem biopsy. CONCLUSION: A medication scheme with tranexamic acid and desmopressin effectively decreased the patient's bleeding time in vivo and the procedure was carried out without complications.


Assuntos
Biópsia/métodos , Transtornos da Coagulação Sanguínea/etiologia , Transtornos da Coagulação Sanguínea/patologia , Tronco Encefálico/patologia , Procedimentos Neurocirúrgicos/métodos , Técnicas Estereotáxicas , Adulto , Antifibrinolíticos/uso terapêutico , Astrocitoma/diagnóstico , Astrocitoma/tratamento farmacológico , Astrocitoma/radioterapia , Tempo de Sangramento , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Desamino Arginina Vasopressina/uso terapêutico , Feminino , Humanos , Ácido Tranexâmico/uso terapêutico , Resultado do Tratamento
16.
ESMO Open ; 6(4): 100214, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34271312

RESUMO

The development of anticancer vaccines as a pillar of cancer immunotherapy has been hampered by the scarcity of suitable tumor-specific antigens. While response to immune checkpoint inhibitors is driven by T cells recognizing mutated antigens, the vast majority of these neoantigens are patient-specific, mandating personalized approaches. In addition, neoantigens are often subclonal present in only a fraction of tumor cells resulting in immune evasion of neoantigen-negative tumor cells. Isocitrate dehydrogenase (IDH)1 mutations, most frequently encoding for the neomorphic protein IDH1R132H, are frequent driver mutations found in the majority of diffuse World Health Organization grade 2 and 3 gliomas. In addition, IDH1R132H generates a shared clonal neoepitope that is recognized by mutation-specific T-helper cells. A recent phase 1 trial (NOA-16, NCT02454634) demonstrated safety and immunogenicity of IDH1-vac, a long IDH1R132H peptide vaccine in patients with newly diagnosed astrocytoma and provided evidence of biological efficacy based on imaging parameters. In addition, vaccine-induced IDH1R132H-reactive tumor-infiltrating T cells were identified. Here we discuss clinical and scientific implications and future developments of IDH-directed immunotherapies.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/genética , Glioma/terapia , Humanos , Isocitrato Desidrogenase/genética , Vacinação
17.
ESMO Open ; 6(6): 100317, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34839103

RESUMO

Immune-related neuromuscular adverse events are rare, but potentially life-threatening side-effects of immune checkpoint inhibitors (ICIs). They usually arise within the first 3 months after initiation of ICIs. Subacute symptom onset with more rapid progression than in idiopathic autoimmune neuromuscular diseases is typical. Prompt clinical diagnosis and treatment is essential for a favourable outcome. The importance of careful medical history and a well-established clinical diagnosis is emphasised rather than antibody detection or radiologic visualisation. Muscle weakness as a leading symptom can give rise to the suspicion of either neuropathy or myositis-myasthenia complex and differentiation may be complicated by their overlap. It is of utmost importance to recognise immune-related myositis and monitor for myocardial as well as bulbar involvement that may rapidly lead to cardiac or respiratory failure, persisting disability or even a fatal outcome. Symptoms typically improve with ICI discontinuation and early administration of glucocorticoids (prednisolone 1-2 mg/kg/day) in patients markedly affected. Severe and persisting symptoms including myocardial or bulbar affection can require therapy escalation to steroid-sparing agents. In patients with mild symptoms, not influencing functional abilities, careful clinical monitoring while staying on ICI therapy may be sufficient. Re-challenging with ICIs may be considered in selected cases, based on the initial severity of immune-related adverse events (irAEs) and clinical disease course. Depending on the individual irAE characteristics, the decision should be preferably discussed in an interdisciplinary irAE expert team with an experienced neurologist, rheumatologist and/or cardiologist and take the patient's preferences into account. The yet unmet need of systematic data on treatment, follow-up results and options of re-challenge of ICI treatment in neuromuscular toxicity has to be particularly considered in the shared decision-making process.


Assuntos
Inibidores de Checkpoint Imunológico , Miosite , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Miosite/induzido quimicamente , Miosite/diagnóstico , Miosite/tratamento farmacológico , Resultado do Tratamento
18.
J Virol ; 83(5): 2349-56, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19091857

RESUMO

Human immunodeficiency virus type 1 (HIV-1) Nef is a multifunctional protein that confers an ability to evade killing by cytotoxic T lymphocytes (CTLs) as well as other advantages to the virus in vivo. Here we exploited mathematical modeling and related statistical methods to estimate the impact of Nef activity on viral replication in vivo in relation to CTLs. Our results indicate that downregulation of major histocompatibility complex class I (MHC-I) A and B by wild-type Nef confers an advantage to the virus of about 82% in decreased CTL killing efficiency on average, meaning that abolishing the MHC-I downregulation function of Nef would increase killing by more than fivefold. We incorporated this estimate, as well as prior estimates of replicative enhancement by Nef, into a previously published model of HIV-1 and CTLs in vivo (W. D. Wick, O. O. Yang, L. Corey, and S. G. Self, J. Virol. 79:13579-13586, 2005), generalized to permit CTL recognition of multiple epitopes. A sequence database analysis revealed that 92.9% of HIV-1 epitopes are A or B restricted, and a previous study found an average of about 19 epitopes recognized (M. M. Addo et al., J. Virol. 77:2081-2092, 2003). We combined these estimates in the model in order to predict the impact of inhibiting Nef function in the general (chronically infected) population by a drug. The predicted impact on viral load ranged from negligible to 2.4 orders of magnitude, depending on the effects of the drug and the CTL dynamical scenario assumed. We conclude that inhibiting Nef could make a substantial reduction in disease burden, lengthening the time before the necessity of undertaking combination therapy with other antiretroviral drugs.


Assuntos
HIV-1/imunologia , Modelos Biológicos , Linfócitos T Citotóxicos/imunologia , Replicação Viral , Produtos do Gene nef do Vírus da Imunodeficiência Humana/metabolismo , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , HIV-1/fisiologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Linfócitos T Citotóxicos/virologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana/imunologia
19.
Eur J Neurol ; 17(9): 1124-1133, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20718851

RESUMO

BACKGROUND: Diffuse infiltrative low-grade gliomas of the cerebral hemispheres in the adult are a group of tumors with distinct clinical, histological and molecular characteristics, and there are still controversies in management. METHODS: The scientific evidence of papers collected from the literature was evaluated and graded according to EFNS guidelines, and recommendations were given accordingly. RESULTS AND CONCLUSIONS: WHO classification recognizes grade II astrocytomas, oligodendrogliomas and oligoastrocytomas. Conventional MRI is used for differential diagnosis, guiding surgery, planning radiotherapy and monitoring treatment response. Advanced imaging techniques can increase the diagnostic accuracy. Younger age, normal neurological examination, oligodendroglial histology and 1p loss are favorable prognostic factors. Prophylactic antiepileptic drugs are not useful, whilst there is no evidence that one drug is better than the others. Total/near total resection can improve seizure control, progression-free and overall survival, whilst reducing the risk of malignant transformation. Early post-operative radiotherapy improves progression-free but not overall survival. Low doses of radiation are as effective as high doses and better tolerated. Modern radiotherapy techniques reduce the risk of late cognitive deficits. Chemotherapy can be useful both at recurrence after radiotherapy and as initial treatment after surgery to delay the risk of late neurotoxicity from large-field radiotherapy. Neurocognitive deficits are frequent and can be caused by the tumor itself, tumor-related epilepsy, treatments and psychological distress.


Assuntos
Comitês Consultivos/tendências , Protocolos Antineoplásicos/normas , Glioma/terapia , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/cirurgia , Terapia Combinada/métodos , Terapia Combinada/normas , Europa (Continente) , Medicina Baseada em Evidências/tendências , Glioma/radioterapia , Glioma/cirurgia , Humanos , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/radioterapia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/cirurgia , Procedimentos Neurocirúrgicos/métodos , Procedimentos Neurocirúrgicos/normas , Prognóstico
20.
Nervenarzt ; 81(8): 928-30, 932-5, 2010 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-20635074

RESUMO

According to the current WHO classification anaplastic gliomas comprise pure astrocytomas and oligodendrogliomas and mixed tumors. This review summarizes findings, discusses problems and defines new questions from the phase III trials on anaplastic gliomas. The molecular subgroup analyses of the NOA-04 trial identified three molecular parameters, which predict longer progression-free and overall survival independent from the mode of therapy, radiotherapy or alkylating chemotherapy-. These are 1p/19q codeletion, methylation of the promoter of the O(6)-methylguanyl methyltransferase (MGMT) gene and hot-spot mutations in the isocitrate dehydrogenase 1 (IDH1) gene. The prognostic relevance of these markers is not lower than that of histopathological subclassification but determination is potentially more robust. Therefore, marker profiles should be included into the next WHO brain tumor classification. The current standard of care for first-line treatment in anaplastic gliomas is radiotherapy or chemotherapy. The next steps, e.g. within the international CATNON trial, are to define the role and optimal sequencing of combined modality treatment focusing on radiotherapy and temozolomide. Inclusion in this trial is already based on the WHO grade and the 1p/19q status and not on the histopathological subtype. Furthermore, anaplastic gliomas are an important group of brain tumors for developing future molecular targeted therapies and should therefore be in the main focus of academic and industrial drug development, which aims at improved efficacy and avoiding long-term side-effects.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Oligodendroglioma/patologia , Antineoplásicos Alquilantes/uso terapêutico , Astrocitoma/diagnóstico , Astrocitoma/genética , Astrocitoma/mortalidade , Astrocitoma/terapia , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Deleção Cromossômica , Ensaios Clínicos como Assunto , Ensaios Clínicos Fase III como Assunto , Terapia Combinada , Irradiação Craniana , Metilases de Modificação do DNA/genética , Análise Mutacional de DNA , Enzimas Reparadoras do DNA/genética , Intervalo Livre de Doença , Humanos , Isocitrato Desidrogenase/genética , Oligodendroglioma/diagnóstico , Oligodendroglioma/genética , Oligodendroglioma/mortalidade , Oligodendroglioma/terapia , Regiões Promotoras Genéticas/genética , Taxa de Sobrevida , Proteínas Supressoras de Tumor/genética
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