Search results for "Brain Neoplasm"
showing 10 items of 249 documents
The activation of ERK1/2 MAP kinases in glioblastoma pathobiology and its relationship with EGFR amplification.
2008
The ERK1/2 activated protein kinase (MAPK) pathway is a critical signaling system that mediates ligand-stimulated signals for the induction of cell proliferation, differentiation and survival, involved in malignant transformation. The purpose of this study was to determine the activation of ERK1/2 in this tumor, and to determine the relationship of ERK1/2 activation with the amplification/overexpression of EGFR as well as with 9p21 locus gene alterations, both of which are genetic factors frequently associated with glioblastoma. We used immunohistochemistry and Western blot analysis to analyze the activation of ERK1/2 in 22 patients with glioblastoma, and we studied the amplification/overex…
Non-negative blind source separation techniques for tumor tissue typing using HR-MAS signals.
2010
Given High Resolution Magic Angle Spinning (HR-MAS) signals from several glioblastoma tumor subjects, the goal is to differentiate between tumor tissue types by separating the different sources that contribute to the profile of each spectrum. Blind source separation techniques are applied for obtaining characteristic profiles for necrosis, high cellular tumor and border tumor tissue, and providing the contribution (abundance) of each tumor tissue to the profile of the spectra. The problem is formulated as a non-negative source separation problem. We illustrate the effectiveness of the proposed methods and we analyze to which extent the dimension of the input space could influence the perfor…
Quantification and classification of high-resolution magic angle spinning data for brain tumor diagnosis.
2007
The goal of this work is to propose a complete protocol (preprocessing, processing and classification) for classifying brain tumors with proton high-resolution magic-angle spinning ((1)H HR-MAS) data. The different steps of the procedure are detailed and discussed. Feature extraction techniques such as peak integration, including also the automated quantitation method AQSES, were combined with linear (LDA) and non-linear (least-squares support vector machine or LS-SVM) classifiers. Classification accuracy was assessed using a stratified random sampling scheme. The results suggest that LS-SVM performs better than LDA while AQSES performs better than the standard peak integration feature extr…
A Novel Semi-Supervised Methodology for Extracting Tumor Type-Specific MRS Sources in Human Brain Data
2013
Background: The clinical investigation of human brain tumors often starts with a non-invasive imaging study, providing \ud information about the tumor extent and location, but little insight into the biochemistry of the analyzed tissue. Magnetic \ud Resonance Spectroscopy can complement imaging by supplying a metabolic fingerprint of the tissue. This study analyses \ud single-voxel magnetic resonance spectra, which represent signal information in the frequency domain. Given that a single \ud voxel may contain a heterogeneous mix of tissues, signal source identification is a relevant challenge for the problem of\ud tumor type classification from the spectroscopic signal.\ud Methodology/Princ…
Prognostic Implications of the Complement Protein C1q in Gliomas
2019
The contribution of the complement system in the pathophysiology of brain cancers has been recently considered in light of its well-known involvement in carcinogenesis. Complement system represents an important component of the inflammatory response, which acts as a functional bridge between the innate and adaptive immune response. C1q, the first recognition subcomponent of the complement classical pathway, has recently been shown to be involved in a range of pathophysiological functions that are not dependent on complement activation. C1q is expressed in the microenvironment of various types of human tumors, including melanoma, prostate, mesothelioma, and ovarian cancers, where it can exer…
Tumor Diagnosis Preceding Alzheimer's Disease Onset: Is There a Link Between Cancer and Alzheimer's Disease?
2012
Studies reporting an inverse association between Alzheimer's disease (AD) and cancer are scant. Available data are mostly based on ancillary findings of mortality data or obtained from studies evaluating frequency of neoplasms in AD patients independently if they occurred before or after AD. Moreover, some studies estimated frequencies of neoplasms in demented individuals, who were not necessarily AD patients. We estimated frequency of tumors preceding the onset of AD in AD patients and compared it to that of age- and gender-matched AD-free individuals. Occurrence of tumors preceding AD onset was assessed through a semi-structured questionnaire. Tumors were categorized as benign, malignant,…
Maternal medication use and the risk of brain tumors in the offspring: The SEARCH international case-control study
2006
International audience; N-nitroso compounds (NOC) have been associated with carcinogenesis in a wide range of species, including humans. There is strong experimental data showing that nitrosamides (R(1)NNO.COR(2)), a type of NOC, are potent neuro-carcinogens when administered transplacentally. Some medications are a concentrated source of amides or amines, which in the presence of nitrites under normal acidic conditions of the stomach can form NOC. Therefore, these compounds, when ingested by women during pregnancy, may be important risk factors for tumors of the central nervous system in the offspring. The aim of the present study was to test the association between maternal use of medicat…
Risk factors for pediatric tumors of the central nervous system: Results from a German population-based case-control study
2001
From 1993 to 1997 we conducted two population-based case-control studies on childhood cancer and a variety of potential risk factors in Germany. One case group involved children under the age of 15 years having a tumor of the central nervous system (CNS).For both studies, one conducted in the northwestern area of Germany, the other covering the whole of West Germany, incident cases were identified from the nationwide German Childhood Cancer Registry, and controls were randomly selected from complete population registration files.In total 466 pediatric CNS tumor cases and 2,458 controls were available for analyses. We observed only few positive associations, namely, between CNS tumors and lo…
Population-based epidemiologic data on brain tumors in German children.
2001
BACKGROUND Brain tumors are the most common disease group of solid tumors in childhood, and children with brain tumors have a relatively poor survival rate. Epidemiologic data from a population-based cancer registry provide the necessary information to obtain a full picture of the frequency of this disease, which is a great challenge in pediatric oncology. METHODS The German Childhood Cancer Registry (GCCR) is a population-based registry. The level of completeness of patient registration is 95%, but it is somewhat lower for patients with brain tumors. More than 300 children with newly diagnosed brain tumors are reported every year. Analyses of GCCR data are performed according to the Intern…
Oral topotecan in children with recurrent or progressive high-grade glioma: a Phase I/II study by the German Society for Pediatric Oncology and Hemat…
2004
BACKGROUND Continuous oral treatment with topotecan may be more effective than the typical 1-day and 5-day treatment schedules. In previous studies of continuous treatment with topotecan, increased intestinal side effects were reported in adult patients; however, the experience in pediatric patients and patients with high-grade glioma is quite limited. METHODS Thirty-two pediatric patients with recurrent high-grade glioma (16 females and 16 males; median age, 9.5 years) were enrolled in the current Phase I/II study. Tumor locations included the cerebral cortex (n = 5), pons (n = 18), and other sites (n = 9). An injectable formulation of topotecan was administered orally, in ice-cold orange …