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1.
Artigo em Inglês | MEDLINE | ID: mdl-38717853

RESUMO

On April 28, 2023, the University of California Office of the President, in partnership with the California Department of Cannabis Control (DCC), hosted the California Cannabis Research Briefing. The California Cannabis Research Briefing brought together researchers and state agencies/policymakers to discuss pertinent policy issues on cannabis within the state. Researchers across six different topic areas (environment, cannabis markets, social equity matters, public health, medicinal cannabis use, and public safety) provided brief explanations of their research and its policy implications. A moderated discussion with stakeholders followed these presentations. The goals of this event were to highlight research that can inform policy issues relevant to the state, and to discuss how research can be incorporated into the cannabis policy landscape.

3.
Cannabis Cannabinoid Res ; 7(2): 152-155, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35451859

RESUMO

This meeting report describes the University of California's (UC) Cannabis Research Workshop on May 26-27, 2021, which was organized by the UC Office of the President (UCOP) in partnership with the University of California, Davis (UCD). The event was designed to explore ways to strengthen research collaborations within and between campuses, discuss federal and state regulations and scientific priorities, and provide updates on current or recent cannabis and cannabinoid research studies. Topical areas were highlighted in four breakout sessions, including: 1) agronomy and environmental impacts; 2) biomedicine and public health; 3) economics, law, public policy, and social science; and 4) administrative considerations for supporting university research on cannabis and cannabinoids.


Assuntos
Canabinoides , Cannabis , Alucinógenos , Analgésicos , Agonistas de Receptores de Canabinoides , Canabinoides/uso terapêutico , Humanos
4.
Cannabis Cannabinoid Res ; 5(2): 183-186, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32656350

RESUMO

On May 30, 2019, the University of California Office of the President, in partnership with University of California, Irvine, hosted a daylong University of California Cannabis Research Workshop designed to explore ways to advance research collaborations on a range of relevant topics, develop a common understanding of the current regulatory framework for conducting cannabis-related research, and formulate next steps for facilitating synergistic cannabis research. This report provides a summary of that meeting.

5.
Mol Pharm ; 16(9): 3791-3801, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31329461

RESUMO

Lafora disease (LD) is a fatal juvenile epilepsy characterized by the accumulation of aberrant glucan aggregates called Lafora bodies (LBs). Delivery of protein-based therapeutics to the central nervous system (CNS) for the clearance of LBs remains a unique challenge in the field. Recently, a humanized antigen-binding fragment (hFab) derived from a murine systemic lupus erythematosus DNA autoantibody (3E10) has been shown to mediate cell penetration and proposed as a broadly applicable carrier to mediate cellular targeting and uptake. We report studies on the efficacy and CNS delivery of VAL-0417, an antibody-enzyme fusion composed of the 3E10 hFab and human pancreatic α-amylase, in a mouse model of LD. An enzyme-linked immunosorbent assay has been developed to detect VAL-0417 post-treatment as a measure of delivery efficacy. We demonstrate the robust and sensitive detection of the fusion protein in multiple tissue types. Using this method, we measured biodistribution in different methods of delivery. We found that intracerebroventricular administration provided robust CNS delivery when compared to intrathecal administration. These data define critical steps in the translational pipeline of VAL-0417 for the treatment of LD.


Assuntos
Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Doença de Lafora/tratamento farmacológico , alfa-Amilases Pancreáticas/genética , alfa-Amilases Pancreáticas/farmacocinética , Animais , Fusão Gênica Artificial/métodos , Encéfalo/metabolismo , Modelos Animais de Doenças , Portadores de Fármacos/metabolismo , Ensaio de Imunoadsorção Enzimática , Glucanos/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Plasmídeos/genética , Proteínas Tirosina Fosfatases não Receptoras/genética , Distribuição Tecidual , Resultado do Tratamento
6.
Cell Metab ; 30(4): 689-705.e6, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31353261

RESUMO

Lafora disease (LD) is a fatal childhood epilepsy caused by recessive mutations in either the EPM2A or EPM2B gene. A hallmark of LD is the intracellular accumulation of insoluble polysaccharide deposits known as Lafora bodies (LBs) in the brain and other tissues. In LD mouse models, genetic reduction of glycogen synthesis eliminates LB formation and rescues the neurological phenotype. Therefore, LBs have become a therapeutic target for ameliorating LD. Herein, we demonstrate that human pancreatic α-amylase degrades LBs. We fused this amylase to a cell-penetrating antibody fragment, and this antibody-enzyme fusion (VAL-0417) degrades LBs in vitro and dramatically reduces LB loads in vivo in Epm2a-/- mice. Using metabolomics and multivariate analysis, we demonstrate that VAL-0417 treatment of Epm2a-/- mice reverses the metabolic phenotype to a wild-type profile. VAL-0417 is a promising drug for the treatment of LD and a putative precision therapy platform for intractable epilepsy.


Assuntos
Encéfalo/efeitos dos fármacos , Descoberta de Drogas , Corpos de Inclusão/efeitos dos fármacos , Doença de Lafora/terapia , alfa-Amilases Pancreáticas/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Células HEK293 , Humanos , Imunoglobulina G/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , alfa-Amilases Pancreáticas/uso terapêutico , Ratos , Proteínas Recombinantes de Fusão/uso terapêutico
8.
Transl Oncol ; 11(4): 941-949, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29883968

RESUMO

The goal of this research was to elucidate the relationship between WHO 2016 molecular classifications of newly diagnosed, nonenhancing lower grade gliomas (LrGG), tissue sample histopathology, and magnetic resonance (MR) parameters derived from diffusion, perfusion, and 1H spectroscopic imaging from the tissue sample locations and the entire tumor. A total of 135 patients were scanned prior to initial surgery, with tumor cellularity scores obtained from 88 image-guided tissue samples. MR parameters were obtained from corresponding sample locations, and histograms of normalized MR parameters within the T2 fluid-attenuated inversion recovery lesion were analyzed in order to evaluate differences between subgroups. For tissue samples, higher tumor scores were related to increased normalized apparent diffusion coefficient (nADC), lower fractional anisotropy (nFA), lower cerebral blood volume (nCBV), higher choline (nCho), and lower N-acetylaspartate (nNAA). Within the T2 lesion, higher tumor grade was associated with higher nADC, lower nFA, and higher Cho to NAA index. Pathological analysis confirmed that diffusion and metabolic parameters increased and perfusion decreased with tumor cellularity. This information can be used to select targets for tissue sampling and to aid in making decisions about treating residual disease.

9.
Nat Cell Biol ; 18(12): 1336-1345, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27820599

RESUMO

Increased overall survival for patients with glioma brain tumours is associated with mutations in the metabolic regulator isocitrate dehydrogenase 1 (IDH1). Gliomas develop within a mechanically challenged microenvironment that is characterized by a dense extracellular matrix (ECM) that compromises vascular integrity to induce hypoxia and activate HIF1α. We found that glioma aggression and patient prognosis correlate with HIF1α levels and the stiffness of a tenascin C (TNC)-enriched ECM. Gain- and loss-of-function xenograft manipulations demonstrated that a mutant IDH1 restricts glioma aggression by reducing HIF1α-dependent TNC expression to decrease ECM stiffness and mechanosignalling. Recurrent IDH1-mutant patient gliomas had a stiffer TNC-enriched ECM that our studies attributed to reduced miR-203 suppression of HIF1α and TNC mediated via a tension-dependent positive feedback loop. Thus, our work suggests that elevated ECM stiffness can independently foster glioblastoma aggression and contribute to glioblastoma recurrence via bypassing the protective activity of IDH1 mutational status.


Assuntos
Neoplasias Encefálicas/patologia , Retroalimentação Fisiológica , Glioblastoma/metabolismo , Glioblastoma/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isocitrato Desidrogenase/metabolismo , Tenascina/metabolismo , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Imunofluorescência , Humanos , Isocitrato Desidrogenase/genética , Mecanotransdução Celular , MicroRNAs/metabolismo , Mutação/genética , Invasividade Neoplásica , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Mol Biosyst ; 10(11): 2889-97, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25105420

RESUMO

Individuals infected with the human immunodeficiency virus (HIV) often suffer from concomitant metabolic complications. Treatment with antiretroviral therapy has also been shown to alter the metabolism of patients. Although chemometric analysis of nuclear magnetic resonance (NMR) spectra of human sera can distinguish normal sera (HIVneg) from HIV-infected sera (HIVpos) and sera from HIV-infected patients on antiretroviral therapy (ART), quantitative analysis of the discriminating metabolites and their relationship to disease status has yet to be determined. The objectives of the study were to analyze NMR spectra of HIVneg, HIVpos, and ART serum samples with a combination of chemometric and quantitative methods and to compare the NMR data with disease status as measured by viral load and CD4 count. High-resolution magic angle spinning (HRMAS) NMR spectroscopy was performed on HIVneg (N = 10), HIVpos (N = 10), and ART (N = 10) serum samples. Chemometric linear discriminant analysis classified the three groups of spectra with 100% accuracy. Concentrations of 12 metabolites were determined with a semi-parametric metabolite quantification method named high-resolution quantum estimation (HR-QUEST). CD4 count was directly associated with alanine (p = 0.008), and inversely correlated with both glutamine (p = 0.017) and glucose (p = 0.022) concentrations. A multivariate linear model using alanine, glutamine and glucose as covariates demonstrated an association with CD4 count (p = 0.038). The combined chemometric and quantitative analysis of the data disclosed previously unknown associations between specific metabolites and disease status. The observed associations with CD4 count are consistent with metabolic disorders that are commonly seen in HIV-infected patients.


Assuntos
Síndrome da Imunodeficiência Adquirida/sangue , Biomarcadores/sangue , Soropositividade para HIV/sangue , Espectroscopia de Ressonância Magnética/métodos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/virologia , Alanina/sangue , Contagem de Linfócito CD4 , Glucose/metabolismo , Glutamina/sangue , Soropositividade para HIV/virologia , Humanos , Carga Viral
11.
J Neurooncol ; 110(3): 305-13, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22983601

RESUMO

Diffuse intrinsic pontine gliomas arise almost exclusively in children, and despite advances in treatment, the majority of patients die within 2 years after initial diagnosis. Because of their infiltrative nature and anatomic location in an eloquent area of the brain, most pontine gliomas are treated without a surgical biopsy. The corresponding lack of tissue samples has resulted in a limited understanding of the underlying genetic and molecular biologic abnormalities associated with pontine gliomas, and is a substantial obstacle for the preclinical testing of targeted therapeutic agents for these tumors. We have established a human glioma cell line that originated from surgical biopsy performed on a patient with a pontine glioma. To insure sustainable in vitro propagation, tumor cells were modified with hTERT (human telomerase ribonucleoprotein reverse transcriptase), and with a luciferase reporter to enable non-invasive bioluminescence imaging. The hTERT modified cells are tumorigenic in athymic rodents, and produce brainstem tumors that recapitulate the infiltrative growth of brainstem gliomas in patients.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Tronco Encefálico/patologia , Glioma/patologia , Ponte , Animais , Biomarcadores Tumorais/metabolismo , Western Blotting , Neoplasias do Tronco Encefálico/genética , Neoplasias do Tronco Encefálico/terapia , Criança , Feminino , Perfilação da Expressão Gênica , Glioma/genética , Glioma/terapia , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Ratos , Ratos Nus , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
12.
Neuro Oncol ; 13(11): 1192-201, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21865401

RESUMO

The apparent diffusion coefficient (ADC) determined from MR diffusion tensor imaging (DTI) has shown promise for distinguishing World Health Organization grade II astrocytoma (AS) from the more prognostically favorable grade II oligodendroglioma (OD). Since mixed oligoastrocytomas (OAs) with codeletions in chromosomes 1p and 19q confer prognoses similar to those of OD, we questioned whether a previously determined ADC-based criterion for distinguishing OD and AS would hold on an independent set of gliomas that included OA with codeleted or intact 1p/19q chromosomes. We also questioned whether the ADC is associated with the tumor microstructure. ADC colormaps generated from presurgical DTI scans were used to guide the collection of biopsies from each tumor. The median normalized ADC distinguished OD from AS with 91% sensitivity and 92% specificity. 1p/19q codeleted OAs were always classified as ODs, while 1p/19q intact OAs were always classified as ASs. There were positive associations between the ADC and both the SMI-31 score of axonal disruption and the fraction of tumor cells in the biopsies. The ADC of OD and 1p/19q codeleted OA was more associated with tumor fraction, while the ADC of AS and 1p/19q intact OA was more associated with SMI-31 score. We conclude that our previously determined threshold median ADC can distinguish grade II OD and AS on a new patient cohort and that the distinctions extend to OA with codeleted and intact 1p/19q chromosomes. Further, the ADC in grade II gliomas is associated with the fraction of tumor cells and degree of axonal disruption in tumor subregions.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Imagem de Difusão por Ressonância Magnética , Oligodendroglioma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/classificação , Astrocitoma/genética , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 19/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Oligodendroglioma/classificação , Oligodendroglioma/genética , Prognóstico , Curva ROC
13.
J Magn Reson Imaging ; 33(4): 808-16, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21448944

RESUMO

PURPOSE: To study choline metabolism in biopsies from nonenhancing Grade 2 (AS2) and Grade 3 (AS3) astrocytomas to determine whether (1) phosphocholine (PC) dominates in AS3, and (2) PC is associated with proliferation or angiogenesis. PC and glycerophosphocholine (GPC) are involved in phospholipid metabolism that accompanies mitosis. PC is the predominant peak in Grade 4 astrocytoma (GBM) while GPC dominates in AS2. MATERIALS AND METHODS: We used high resolution magic angle spinning magnetic resonance spectroscopy to compare the concentrations of 10 metabolites in 41 biopsies (16 AS2 and 25 AS3) from 24 tumors. Immunohistochemistry was performed on paired biopsies to determine the cell density, Ki-67 proliferation index, and vascular endothelial growth factor (VEGF) angiogenic marker expression. RESULTS: AS3 had higher PC than AS2; however, the PC:GPC was less than 1 in all cases irrespective of tumor grade. Within tumors, GPC increased with Ki-67 and PC and tCho increased with cell density. There was no association between any choline compound and VEGF. CONCLUSION: These data suggest that PC:GPC less than 1 is not unique to low grade glioma. Furthermore, the PC concentration that is a marker of aggressive glial tumors is not tightly linked to cell proliferation or angiogenesis in nonenhancing astrocytomas.


Assuntos
Astrocitoma/patologia , Colina/metabolismo , Adulto , Astrocitoma/metabolismo , Biópsia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Feminino , Glioma/metabolismo , Glicerilfosforilcolina/farmacologia , Humanos , Imuno-Histoquímica/métodos , Antígeno Ki-67/biossíntese , Espectroscopia de Ressonância Magnética/métodos , Masculino , Neovascularização Patológica , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Cancer Cell ; 18(6): 669-82, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-21156288

RESUMO

Malignant astrocytic brain tumors are among the most lethal cancers. Quiescent and therapy-resistant neural stem cell (NSC)-like cells in astrocytomas are likely to contribute to poor outcome. Malignant oligodendroglial brain tumors, in contrast, are therapy sensitive. Using magnetic resonance imaging (MRI) and detailed developmental analyses, we demonstrated that murine oligodendroglioma cells show characteristics of oligodendrocyte progenitor cells (OPCs) and are therapy sensitive, and that OPC rather than NSC markers enriched for tumor formation. MRI of human oligodendroglioma also suggested a white matter (WM) origin, with markers for OPCs rather than NSCs similarly enriching for tumor formation. Our results suggest that oligodendroglioma cells show hallmarks of OPCs, and that a progenitor rather than a NSC origin underlies improved prognosis in patients with this tumor.


Assuntos
Neoplasias Encefálicas/patologia , Células-Tronco Neurais/patologia , Oligodendroglia/patologia , Oligodendroglioma/patologia , Animais , Antígenos/análise , Benzamidas/farmacologia , Diferenciação Celular , Linhagem Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Humanos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Oncogênicas v-erbB/análise , Proteoglicanas/análise , Temozolomida , Proteína Supressora de Tumor p53/fisiologia
15.
NMR Biomed ; 22(4): 449-55, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19125391

RESUMO

Distinguishing between low-grade oligodendrogliomas (ODs) and astrocytomas (AC) is of interest for defining prognosis and stratifying patients to specific treatment regimens. The purpose of this study was to determine if the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) from diffusion imaging can help to differentiate between newly diagnosed grade II OD and AC subtypes and to evaluate the ADC and FA values for the mixed population of oligoastrocytomas (OA). Fifty-three patients with newly diagnosed grade II gliomas were studied using a 1.5T whole body scanner (23 ODs, 16 ACs, and 14 OAs). The imaging protocol included post-gadolinium T1-weighted images, T2-weighted images, and either three and/or six directional diffusion imaging sequence with b = 1000 s/mm(2). Diffusion-weighted images were analyzed using in-house software to calculate maps of ADC and for six directional acquisitions, FA. The intensity values were normalized by values from normal appearing white matter (NAWM) to generate maps of normalized apparent diffusion coefficient (nADC) and normalized fractional anisotropy (nFA). The hyperintense region in the T2 weighted image was defined as the T2All region. A Mann-Whitney rank-sum test was performed on the 25th, median, and 75th nADC and nFA among the three subtypes. Logistic regression was performed to determine how well the nADC and nFA predict subtype. Lesions diagnosed as being OD had significantly lower nADC and significantly higher nFA, compared to AC. The nADC and nFA values individually classified the data with an accuracy of 87%. Combining the two did not enhance the classification. The patients with OA had nADC and nFA values between those of OD and AC. This suggests that ADC and FA may be helpful in directing tissue sampling to the most appropriate regions for taking biopsies in order to make a definitive diagnosis.


Assuntos
Imagem de Difusão por Ressonância Magnética , Glioma/diagnóstico , Adulto , Idoso , Anisotropia , Feminino , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Neuroimage ; 47 Suppl 2: T27-35, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19095069

RESUMO

We are developing a method for real-time magnetic resonance imaging (MRI) visualization of convection-enhanced delivery (CED) of adeno-associated viral vectors (AAV) to the primate brain. By including gadolinium-loaded liposomes (GDL) with AAV, we can track the convective movement of viral particles by continuous monitoring of distribution of surrogate GDL. In order to validate this approach, we infused two AAV (AAV1-GFP and AAV2-hAADC) into three different regions of non-human primate brain (corona radiata, putamen, and thalamus). The procedure was tolerated well by all three animals in the study. The distribution of GFP determined by immunohistochemistry in both brain regions correlated closely with distribution of GDL determined by MRI. Co-distribution was weaker with AAV2-hAADC, although in vivo PET scanning with FMT for AADC activity correlated well with immunohistochemistry of AADC. Although this is a relatively small study, it appears that AAV1 correlates better with MRI-monitored delivery than does AAV2. It seems likely that the difference in distribution may be due to differences in tissue specificity of the two serotypes.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/virologia , Dependovirus/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Animais , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Encéfalo/fisiologia , Gadolínio , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Imuno-Histoquímica , Lipossomos , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Putamen/virologia , Tálamo/virologia
17.
J Magn Reson Imaging ; 27(4): 718-25, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18383265

RESUMO

PURPOSE: To examine the relationship between apparent diffusion coefficients (ADC) from diffusion weighted imaging (DWI) and choline levels from proton magnetic resonance spectroscopic imaging (MRSI) in newly diagnosed Grade II and IV gliomas within distinct anatomic regions. MATERIALS AND METHODS: A total of 37 patients with Grade II and 28 patients with Grade IV glioma were scanned on a 1.5T system with 3D MRSI and DWI. Region level analysis included Spearman rank correlation between median normalized ADC and choline for each patient per grade within each distinct abnormal anatomical region. Voxel level analysis calculated a Spearman rank correlation per region, per patient. RESULTS: Grade II lesions showed no evidence of a correlation between normalized ADC and choline using either the region or voxel level analysis. Region level analysis of Grade IV lesions did not appear to correlate in the contrast enhancement or necrotic core, but did suggest a significant negative correlation in the more heterogeneous nonenhancing and combined regions. CONCLUSION: There appears to be differences in the relationship between ADC and choline levels in Grade II and Grade IV gliomas. Correlation within these regions in Grade IV lesions was strongest when all regions were included, suggesting heterogeneity may be driving the relationship.


Assuntos
Neoplasias Encefálicas/patologia , Colina/análise , Imagem de Difusão por Ressonância Magnética , Glioma/patologia , Espectroscopia de Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Química Encefálica , Neoplasias Encefálicas/química , Feminino , Glioma/química , Glioma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
19.
Int J Radiat Oncol Biol Phys ; 70(3): 773-81, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18262090

RESUMO

PURPOSE: To investigate the association between magnetic resonance spectroscopic imaging (MRSI)-defined, metabolically abnormal tumor regions and subsequent sites of relapse in data from patients treated with radiotherapy (RT) in a prospective clinical trial. METHODS AND MATERIALS: Twenty-three examinations were performed prospectively for 9 patients with newly diagnosed glioblastoma multiforme studied in a Phase I trial combining Tipifarnib and RT. The patients underwent magnetic resonance imaging (MRI) and MRSI before treatment and every 2 months until relapse. The MRSI data were categorized by the choline (Cho)/N-acetyl-aspartate (NAA) ratio (CNR) as a measure of spectroscopic abnormality. CNRs corresponding to T1 and T2 MRI for 1,207 voxels were evaluated before RT and at recurrence. RESULTS: Before treatment, areas of CNR2 (CNR > or =2) represented 25% of the contrast-enhancing (T1CE) regions and 10% of abnormal T2 regions outside T1CE (HyperT2). The presence of CNR2 was often an early indicator of the site of relapse after therapy. In fact, 75% of the voxels within the T1CE+CNR2 before therapy continued to exhibit CNR2 at relapse, compared with 22% of the voxels within the T1CE with normal CNR (p < 0.05). The location of new contrast enhancement with CNR2 corresponded in 80% of the initial HyperT2+CNR2 vs. 20.7% of the HyperT2 voxels with normal CNR (p < 0.05). CONCLUSION: Metabolically active regions represented a small percentage of pretreatment MRI abnormalities and were predictive for the site of post-RT relapse. The incorporation of MRSI data in the definition of RT target volumes for selective boosting may be a promising avenue leading to increased local control of glioblastomas.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Espectroscopia de Ressonância Magnética , Recidiva Local de Neoplasia/metabolismo , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/radioterapia , Colina/metabolismo , Feminino , Glioblastoma/diagnóstico , Glioblastoma/radioterapia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Valor Preditivo dos Testes , Estudos Prospectivos , Prótons
20.
J Neurosurg ; 106(4): 660-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17432719

RESUMO

OBJECT: The accurate diagnosis of World Health Organization Grades II and III gliomas is crucial for the effective treatment of patients with such lesions. Increased cell density and mitotic activity are histological features that distinguish Grade III from Grade II gliomas. Because increased cellular proliferation and density both contribute to the in vivo magnetic resonance (MR) spectroscopic peak corresponding to choline-containing compounds (Cho), the authors hypothesized that multivoxel MR spectroscopy might help identify the tumor regions with the most aggressive growth characteristics, which would be optimal locations for biopsy. They investigated the ability to use one or more MR spectroscopic parameters to predict the MIB-1 cell proliferation index (PI), the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling cell death index (DI), the cell density, and the ratio of proliferation to cell death (PI/DI) within different regions of the same tumor. METHODS: Patients with presumed Grades II or III glioma underwent 3D MR spectroscopic imaging prior to surgery, and two or three regions within the tumor were targeted for biopsy retrieval based on their spectroscopic features. Biopsy specimens were extracted from the tumor during image-guided resection, and the PI, DI, and cell density were assessed in the specimens using immunohistochemical methods. CONCLUSIONS: The authors found that the relative levels of Cho and N-acetylaspartate (NAA) correlated with the cell density, PI, and PI/DI ratio within different regions of the same tumor and that the association held for the subpopulation of nonenhancing tumors. The association was stronger in tumors with large ranges of Cho/NAA values, irrespective of the presence of contrast enhancement. The findings demonstrate the validity of using MR spectroscopy to identify regions of aggressive growth in presumed Grade II or III gliomas that would be suitable targets for retrieving diagnostic biopsy specimens.


Assuntos
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Colina/metabolismo , Glioma/metabolismo , Glioma/patologia , Espectroscopia de Ressonância Magnética , Anticorpos Antinucleares/metabolismo , Anticorpos Monoclonais/metabolismo , Apoptose/fisiologia , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Proliferação de Células , Creatina/metabolismo , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
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