ABSTRACT
Tumour growth and spread of tumour cells requires angiogenesis. Incipient angiogenesis is not induced by tumour cell hypoxia but probably by proangiogenic factors. During growth tumours depend on a further induction of vascular development for adequate oxygen and nutrient supply. If the oxygen supply is insufficient, the resulting hypoxia stimulates angiogenesis through upregulation of HIF-1 alpha and VEGF. VEGF upregulation is associated with a poor response to treatment and poor prognosis. The aim of the study was to analyze the interrelationship between hypoxia and angiogenesis during tumour growth. Therefore the tumour vasculature architecture and functional properties of the vessels were studied during subsequent phases of tumour growth in relation to hypoxia and VEGF-expression. Tumours from the human glioblastoma multiforme tumour line E106 were transplanted in athymic mice. Tumours were harvested at 2 days after transplantation and when tumours reached a mean size of 2, 4, 6, 8 and 10 mm. VEGF was present early in the onset of angiogenesis independent of HIF-1 alpha. During tumour growth VEGF increased from 0.94 to 7.27 ng/mg assessed by ELISA. However, there was increasing intratumoural heterogeneity in the architecture of the tumours, even in the largest tumours small well oxygenated areas were detected resembling the relatively well organized architecture of the smallest tumours. The observation that tumour vasculature develops in early phases under normoxic and at later phases under hypoxic conditions with the presence of both conditions in the larger tumours, suggested that anti-angiogenic therapy should be directed towards HIF-1 alpha dependent and HIF 1-alpha independent pathways.
Subject(s)
Glioblastoma/blood supply , Glioblastoma/metabolism , Vascular Endothelial Growth Factor A/metabolism , Animals , Blood Vessels/pathology , Cell Line, Tumor , Enzyme-Linked Immunosorbent Assay , Glioblastoma/pathology , Humans , Hypoxia/metabolism , Hypoxia/pathology , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mice , Mice, Nude , Neoplasm Transplantation , Neovascularization, Pathologic/metabolism , Transplantation, HeterologousABSTRACT
Oligodendroglial tumors may not be distinguished easily from other brain tumors based on clinical presentation and magnetic resonance imaging (MRI) alone. Identification of these tumors however may have therapeutic consequences. The purpose of this study was to characterize and identify oligodendrogliomas by their metabolic profile as measured by (1)H MR spectroscopic imaging (MRSI). Fifteen patients with oligodendroglial tumors (eight high-grade oligodendrogliomas, seven low-grade oligodendrogliomas) underwent MRI and short echo time (1)H MRSI examinations. Five main metabolites found in brain MR spectra were quantified and expressed as ratios of tumor to contralateral white matter tissue. The level of lipids plus lactate was also assessed in the tumor. For comparison six patients with a low grade astrocytoma were also included in the study. The metabolic profile of oligodendrogliomas showed a decreased level of N-acetylaspartate and increased levels of choline-containing compounds and glutamine plus glutamate compared with white matter. The level of glutamine plus glutamate was significantly higher in low-grade oligodendrogliomas than in low-grade astrocytomas and may serve as a metabolic marker in diagnosis and treatment planning. In high-grade oligodendrogliomas large resonances of lipids plus lactate were observed in contrast to low-grade tumors.
Subject(s)
Aspartic Acid/analogs & derivatives , Biomarkers, Tumor/metabolism , Magnetic Resonance Spectroscopy , Oligodendroglioma/diagnosis , Oligodendroglioma/metabolism , Adult , Aspartic Acid/chemistry , Aspartic Acid/metabolism , Biomarkers, Tumor/chemistry , Brain Neoplasms/chemistry , Brain Neoplasms/diagnosis , Brain Neoplasms/metabolism , Choline/chemistry , Choline/metabolism , Dipeptides/chemistry , Dipeptides/metabolism , Female , Glutamic Acid/chemistry , Glutamic Acid/metabolism , Glutamine/chemistry , Glutamine/metabolism , Humans , Inositol/chemistry , Inositol/metabolism , Male , Middle Aged , Oligodendroglioma/chemistry , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Two cases of neuralgic amyotrophy (idiopathic brachial plexus neuropathy) in children are presented and combined with a review of the literature. Difficulties in establishing the diagnosis are illustrated, and we give an overview of the phenotype of childhood neuralgic amyotrophy and its distinctions from the adult type. Pain, in adult cases present in over 95% of the cases, is less frequent in children, and its absence by no means excludes the diagnosis. In children under 8 weeks of age, the literature shows that a subsequent osteomyelitis of the shoulder or arm always seems to be involved, which warrants a close follow-up. Overall, recovery is less favourable in children, but when they fully recover they seem to do so in a shorter period of time than adults. We conclude that neuralgic amyotrophy in children is distinct from the adult variety, and that it has a definite place in the differential diagnosis of a sudden limp arm, even if it is painless.
