MGMT promoter methylation status and prognosis of patients with primary or recurrent glioblastoma treated with carmustine wafers.

The prognostic role of O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation in glioblastoma patients treated with carmustine (BCNU) wafer implantation is unclear. Here, we report on a retrospective study of 47 patients with either newly diagnosed (30 patients) or recurrent (17 patients) glioblastoma (WHO grade IV) treated with BCNU (bis-chloroethylnitrosourea) wafers. Thirteen of the newly diagnosed patients received local BCNU and irradiation only (first-line BCNU), while 17 patients additionally received concomitant and adjuvant temozolomide (TMZ) radiochemotherapy (first-line BCNU + TMZ). Of the 17 patients treated for recurrent glioblastoma (second-line BCNU), 16 had received radiotherapy with concomitant and adjuvant TMZ as an initial treatment. Median overall survival (OS) did not significantly differ between 19 patients with MGMT promoter methylated tumors when compared to 28 patients with unmethylated tumors (18.9 vs 15.0 months; p = 0.1054). In the first-line BCNU + TMZ group, MGMT promoter methylation was associated with longer OS (21.0 vs 11.1 months, p = 0.0127), while no significant survival differences were detected in the other two subgroups. Progression-free survival did not significantly differ between patients with and without MGMT promoter methylated tumors in the entire patient cohort or any of the three subgroups. The first-line BCNU + TMZ group showed no significant difference in OS when compared to the first-line BCNU group (18.9 vs 14.7 months), but tended to have more therapy-related adverse effects (53% vs 24%, p = 0.105). In summary, MGMT promoter methylation showed a non-significant trend toward longer survival in our patient cohort. The combination of TMZ radiochemotherapy with local delivery of BCNU did not provide a significant survival benefit compared to local BCNU alone, but was associated with a higher rate of adverse effects. Owing to the small number of patients investigated, however, these findings would need to be corroborated in larger patient cohorts.

pH measurement as quality control on human post mortem brain tissue: a study of the BrainNet Europe consortium.

AIMS: Most brain diseases are complex entities. Although animal models or cell culture experiments mimic some disease aspects, human post mortem brain tissue remains essential to advance our understanding of brain diseases using biochemical and molecular techniques. Post mortem artefacts must be properly understood, standardized, and either eliminated or factored into such experiments. Here we examine the influence of several premortem and post mortem factors on pH, and discuss the role of pH as a biochemical marker for brain tissue quality. METHODS: We assessed brain tissue pH in 339 samples from 116 brains provided by 8 different European and 2 Australian brain bank centres. We correlated brain pH with tissue source, post mortem delay, age, gender, freezing method, storage duration, agonal state and brain ischaemia. RESULTS: Our results revealed that only prolonged agonal state and ischaemic brain damage influenced brain tissue pH next to repeated freeze/thaw cycles. CONCLUSIONS: pH measurement in brain tissue is a good indicator of premortem events in brain tissue and it signals limitations for post mortem investigations.

Epigenetic repression of RASSF1A but not CASP8 in supratentorial PNET (sPNET) and atypical teratoid/rhabdoid tumors (AT/RT) of childhood.

Supratentorial primitive neuroectodermal tumors (sPNET) and atypical teratoid/rhabdoid tumors (AT/RT) of the CNS represent a biological and clinical enigma, despite advances in both molecular techniques and clinical management for these two rare embryonal brain tumors of childhood. Epigenetic changes hold great potential as possible disease mechanisms and may be manipulated therapeutically. We thus studied aberrant methylation of the genes RASSF1A and CASP8 and its consequence on expression in cell lines and primary tumors using a combination of semiquantitative methylation specific PCR (MSP), bisulfite sequencing and RT-PCR. In all, 17 samples of autopsy-derived normal appearing brain served as controls. Opposed to control tissues 19/24 sPNET and 4/6 AT/RT demonstrated aberrant methylation for the RASSF1A promoter region. Treatment of cell lines using 5-Aza-2'-deoxycytidine (5AZA) alone or in combination with trichostatin A (TSA) succeeded in re-establishing expression of RASSF1A in cell lines derived from a renal rhabdoid, an AT/RT and a medulloblastoma. A 5' CpG-rich region of CASP8 was methylated in normal tissues and in tumors. However, CASP8 showed inconsistent expression patterns in normal and tumor tissues. Our results indicate that aberrant methylation of the RASSF1A promoter region may be of importance in the origin and progression of sPNET and AT/RT while the analysed 5'-CpG rich region of the CASP8 gene does not seem to play an important role in these tumors. Further studies of epigenetic changes in these rare tumors are warranted as their biology remains obscure and treatment efforts have been rather unsuccessfull.

Alterations in expression of glutamatergic transporters and receptors in sporadic Alzheimer's disease.

Excitatory neurotransmitter dysfunction has been discussed to be involved in the pathophysiology of Alzheimer's disease (AD). In the current study we investigated gene and protein expression patterns of glutamatergic receptors and transporters in brains of AD patients in various stages of disease using gene chip arrays, real time PCR and immunohistochemistry. We found marked impairment in the expression of excitatory amino acid transporters (EAAT1 and EAAT 2) at both gene and protein levels in hippocampus and gyrus frontalis medialis of AD patients, already in early clinical stages of disease. The loss of EAAT immunoreactivity was particularly obvious in the vicinity of amyloid plaques. In contrast, EAAT expression was up-regulated in the cerebellum of these patients. Furthermore, a significant up-regulation of the glutamatergic kainate (GRIK4) receptor observed by gene arrays was confirmed by quantitative RT-PCR in late stages in the hippocampus of AD patients. Moreover, there were down-regulations of other glutamatergic receptors such as NMDA (GRINL1A) and AMPA (GRIA4) receptors. Our data show marked changes in the functional elements of the glutamatergic synapses such as glutamatergic receptors and transporters and indicate impaired glutamate clearing rendering neurons susceptible to excess extracellular glutamate and support further the involvement of excitotoxic mechanisms in the pathogenesis of AD.

Neuronal and ependymal expression of selenoprotein P in the human brain.

Selenoprotein P (SePP) is central to selenium (Se) metabolism in the mammalian organism. Human SePP contains 10 Se atoms that are covalent constituents of the polypeptide chain incorporated as the rare amino acid selenocysteine (Sec). Since hepatocytes secrete SePP into plasma, SePP is commonly regarded as a Se transport protein, although SePP mRNA is expressed in many organs. Gene targeting of SePP in mice leads to neurological dysfunction resulting from Se deficiency and associated reduction of selenoenzyme activities in the brain. However, more recent data revealed that isolated hepatic SePP deficiency does not alter brain Se levels, suggesting a role for SePP locally expressed in the brain. Some of the best characterized and most abundant selenoenzymes, glutathione peroxidases, thioredoxin reductases, and methionine sulfoxide reductase B, play major roles in the cellular defense against reactive oxygen species. Therefore, it was hypothesized that reduced brain Se bioavailability may be involved in the pathogenesis of neurodegenerative disease and normal ageing. We present evidence that human CSF contains SePP and that the human brain expresses SePP mRNA. Moreover, SePP-like immunoreactivity localizes to neurons and ependymal cells and thus appears strategically situated for maintenance and control of Se-dependent anti-oxidative defense systems.

Effects of transforming growth factor-beta 1 on collagen synthesis, integrin expression, adhesion and invasion of glioma cells.

Transforming growth factor-beta 1 (TGF-beta 1) as a potent modulator of cell-extracellular matrix (ECM) interactions may be related to poorly understood ECM-associated features of glioblastomas, such as diffuse brain invasion, rarity of extracranial metastasis and marked ECM production in vitro. We therefore studied TGF-beta 1 expression in glioblastoma biopsy specimens and cell lines by using reverse transcription-polymerase chain reaction (RT-PCR). The cell lines were also examined by Western blotting and immunocytochemistry. To determine effects of TGF-beta 1, glioma cell lines U-138MG and U-373MG were incubated for 48 hours with TGF-beta 1 (0.1, 1, 10 ng/ml) or with antisense phosphorothioate-oligodeoxynucleotides (APO) designed to specifically inhibit TGF-beta 1 gene expression. Thereafter, collagen synthesis was determined by isotopic labeling with 3H-proline; integrin expression by flow cytometry; adhesion on collagen types I and IV, laminin and fibronectin by adhesion assays; and invasion through reconstituted basement membrane by invasion assays. We found that TGF-beta 1 was expressed by all glioma cell lines at protein and mRNA levels. Pretreatment with TGF-beta 1 increased the amount of collagen synthesis/cell, upregulated the alpha 5 integrin chain of U-138MG cells, and facilitated adhesion on all ECM substrates, while invasion of U-138MG cells, but not that of U-373MG cells, was markedly reduced. Conversely, pretreatment with APO reduced TGF-beta 1 protein expression levels, inhibited adhesion and increased invasion of U-138MG cells, but did not affect collagen synthesis. We conclude that exogenously applied TGF-beta 1 exerts marked effects on ECM-related features of glioma cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Myelinoclastic diffuse sclerosis (Schilder's disease): cliniconeuroradiologic correlations.

We report a 17-year-old boy with myelinoclastic diffuse sclerosis (Schilder's disease) presenting with left leg paresis, visual loss, and behavioral changes. CT and MRI showed two large lesions in the subcortical white matter of the occipital and parietal lobes of both hemispheres and increased intracranial pressure. Histology disclosed large areas of demyelination and perivascular infiltrates. The patient improved with coincident oral prednisolone treatment.

Primary intracerebral Hodgkin's disease: report of a case with Epstein-Barr virus association and review of the literature.

A case of primary intracerebral Hodgkin's disease (HD) without dural attachment in a 54-year-old immunocompetent patient is described. The infiltrate was located superficially in the occipital lobe and corresponded to the histologic type of nodular sclerosis. A typical immunohistochemical profile (membrane and cytoplasmic staining with dotlike Golgi enhancement of CD30, moderate cytoplasmic staining of CD15 in the Golgi area, membrane staining of CD20 of <10% of blastic cells, CD45RB negative) and in addition Epstein-Barr virus (EBV) latent membrane protein was detectable in Reed-Sternberg cells. Staging revealed no other organ sites of involvement. After combined surgery, postoperative radiotherapy, and chemotherapy, there are no signs of recurrence or systemic disease on follow-up for >1 year. To the authors' best knowledge, an association of EBV with primary central nervous system HD has not been demonstrated before.

Histiocytic tumor of Meckel's cave. An intracranial equivalent of juvenile xanthogranuloma of the skin.

We present the case of a 7-year-old boy who had a solitary mass within Meckel's cave that recurred 6 weeks after the initial resection. The histological, immunohistochemical, electron-microscopical, and molecular genetical features established the lesion's histiocytic nature. Our findings showed that it was closely related to juvenile xanthogranuloma, a benign lesion that usually occurs in the skin but has not yet been histologically confirmed in the brain. The present tumor is different from other intracranial histiocytic and xanthogranulomatous lesions.

Monoclonal antibody analysis of major histocompatibility complex expression in human meningiomas.

Using monoclonal antibodies (MAB) in combination with the alkaline phosphatase anti-alkaline phosphatase technique, 20 meningiomas were examined for the expression of major histocompatibility complex (MHC) antigens. Most of the tumor cells were labeled with the MAB for class I MHC antigens. In addition, class I reactivity was seen in the tumor blood vessels, presumably reflecting labeling of the endothelial cells. Tumor cells and endothelium were not labeled with the MAB for class II MHC antigen HLA-DR. Occasionally a staining of periendothelial cells was detected. The presence of MHC antigens supports the assumption that endothelial cells play a role in antigen presentation, perhaps relevant to the initiation of an immune response, and that meningioma cells can be a target of T cell-mediated immune reactions.

Effect of embolisation of meningioma on Ki-67 proliferation index.

The proliferation indices (PIs) were determined in 33 meningiomas using two monoclonal antibodies to the Ki-67 antigen (Ki-67 and MIB1). PIs obtained using Ki-67 on frozen material were intermediate between the lowest and highest MIB1 PIs determined in paraffin wax sections. Preoperative embolisation did not influence Ki67 PI, but four of the 15 embolised tumours showed substantially increased MIB1 PIs around embolisation necroses. Proliferation can be reliably assessed in routinely processed meningioma tissues using MIB1; and increased perinecrotic PIs may occur in embolised meningiomas without being an indication of malignancy.

Mitochondrial encephalomyopathy with pilovacuolar inclusion or phenocopy with mitochondrial artefact?

The case of a 33-year-old man with clinical features of mitochondrial encephalomyopathy is presented. He suffered from recurrent cerebral infarctions, cerebellar ataxia, deafness, retinopathy, weakness, and cardiac and renal disorders. Biochemical and light microscope investigations of skeletal muscle did not show any mitochondrial abnormality. Electron microscopy revealed the presence of a hitherto unreported peculiar "pilovacuolar" inclusion in numerous mitochondria, composed of an electron dense pile or rod within a vacuole, while globular or crystalline inclusions were absent.

Adult-onset rod disease with abundant intranuclear rods.

The third case of adult-onset rod disease (nemaline myopathy) with abundant myofibrillar as well as intranuclear rods is described. The 61-year-old woman suffered from progressive weakness of proximal extremities and of the neck, mimicking polymyositis. Muscle biopsy revealed a striking myopathic pattern, with intranuclear rods occurring in 31% of the fibres. On light and electron microscopy and by immunohistochemical study, the rods differed from myofibrillar rods. The absence of alpha-actinin in intranuclear rods suggests an enhanced readiness of actin filaments to bind to diverse proteins, instead of overproduction of alpha-actinin as the pathogenetic basis of the rod formation.

Ragged-red fibres detected in paraffin sections by a monoclonal antibody to inner mitochondrial membrane.

An immunohistochemical method is reported using the M-II68 monoclonal antibody, which detects mitochondrial accumulations ("ragged-red fibres") in routinely processed (formalin-fixed, paraffin-embedded) muscle tissue. Ten cases with electron-microscopically and histochemically proven mitochondrial myopathy featured 4% to 24% ragged-red fibres. In a series of 50 muscle biopsies without mitochondrial myopathy, scattered ragged-red fibres (less than 0.1%) were present in a few normal and pathological muscles. The immunohistochemical method is specific for mitochondria, does not require frozen tissue and permits rapid examination of large areas.

Long-term survival of glioblastoma multiforme: importance of histopathological reevaluation.

The overall prognosis for patients with glioblastoma multiforme is extremely poor. However, a small proportion of patients enjoy prolonged survival. This study investigated retrospectively the extent to which erroneous histopathological classification may contribute to long-term survival of patients initially diagnosed with "glioblastoma multiforme." We compared two age- and gender-matched patient groups with different postoperative time to tumor progression (TTP), defined as "short-term" for TTP of less than 6 months (n = 54), and "long-term" for TTP of more than 12 months (n = 52). Histological specimens of the corresponding tumors, all primarily diagnosed as glioblastoma multiforme, were reevaluated according to the current World Health Organization (WHO) classification of central nervous system tumors, with the investigators being blinded to clinical outcome. Among the tumors from short-term TTP patients, one tumor (2%) was reclassified as anaplastic oligoastrocytoma (WHO grade III) while the remaining 53 were confirmed as glioblastoma multiforme. In contrast, 13 tumors (25%) from the long-term TTP patients were reclassified, mostly as anaplastic oligodendroglioma (WHO grade III; n = 7) or anaplastic oligoastrocytoma (WHO grade III, n = 2), respectively. In addition, three were reclassified as anaplastic astrocytoma (WHO grade III), and one was identified as anaplastic pilocytic astrocytoma (WHO grade III). Our data indicate that a sizable proportion of glioblastoma patients with long-term survival actually carry malignant gliomas with oligodendroglial features. The correct histopathological recognition of these tumors has not only prognostic but also therapeutic implications, since oligodendroglial tumors are more likely to respond favorably to chemotherapy.

Simultaneous bilateral diffuse melanocytic uveal hyperplasia.

A 52-year-old woman noted loss of vision in August 1984. Clinical examination disclosed iris cysts and ciliary body cysts, macular edema, and uveal nevi. Cataract extraction and pressure-lowering operations were required in both eyes because of a tumor-induced angle-closure glaucoma. Vision, however, progressively decreased to light perception in each eye. Both eyes were finally enucleated because a malignant melanoma could not be ruled out, though iris tissue obtained in 1985 suggested a nevuslike process. Histologic study indicated a bilateral uveal hyperplasia. Results of light and electron microscopy, immunologic studies, and suspension cell culture suggested that the uveal hyperplasia was more likely a melanoma of low malignancy than a nevuslike process. We could not detect an extraocular primary tumor and assumed that this condition constituted an oncogenic syndrome.

Morphological alterations of the degenerated lumbar disc following chemonucleolysis with chymopapain.

Lumbar disc tissue from 10 patients who had previously undergone chemonucleolysis without success was studied by light and scanning electron microscopy. Seven patients had a sequestrated disc; three had large protrusions. As a control, material from 10 patients subjected to disc surgery without previous chemonucleolysis was studied in the same way. The control discs revealed the characteristic signs of degeneration: alteration of the collagen, microcystic areas, and giant chondromas. Changes following chemonucleolysis were restricted exclusively to the ground substance and characterized by a marked loss of basophilia in the cartilage matrix. There was no involvement of the anulus fibrosus, cartilage plate, or bone. Following chymopapain administration, scanning electron microscopy showed a naked collagen network devoid of ground substance.

Interleukin 10 is expressed in human gliomas in vivo and increases glioma cell proliferation and motility in vitro.

Interleukin 10 (IL-10) is a cytokine with a broad spectrum of immunosuppressive activity, but itoffs role in the oncogenesis of solid tumors is still unclear. In previous experiments we have shown that IL-10 specific mRNA is produced within glial tumors in vivo. The aim of the present study was to investigate the expression of the IL-10 protein in vivo and to identify the cells producing IL-10 within the tumor tissue. Expression levels significantly increased with malignancy of the gliomas. 87.5% of grade III and IV, but only 4% of grade II tumors expressed high levels of mRNA. Elevation of IL-10 serum levels was found in 11% of low grade and in 63.6% of high grade glioma patients. In situ hybridization analysis with combined immunohistochemistry revealed that: a) IL-10 is not produced by infiltrating B- or T- lymphocytes, b) both microglia and astroglia contributed to IL-10 expression in malignant gliomas in vivo. These data suggested the functional role of IL-10 in glioma progression. Therefore, the effects of IL-10 on proliferation and migration of glioma cells were determined in vitro. Two human glioma cell lines were grown as monolayer as well as spheroids in the presence of different concentrations of IL-10. IL-10 increased cell proliferation significantly in both culture systems with a dose optimum of 25 ng/ml. Glioma cell motility was enhanced with 25 ng/ml as the optimal dose. Adding the IL-10 specific antibody reversed both effects. We conclude from our data that IL-10 is involved in the progression of glial tumors, especially in the enhancement of tumor cell proliferation and migration which promotes infiltration of the surrounding tissue.

Meningio-angiomatosis.

A case is described of a boy five years old who suffered from left-sided muscular weakness since the first months of life and from absences since the second year of life. He died of valproate-induced hepatic insufficiency. Autopsy of the brain revealed meningio-angiomatosis, a rare but rather benign disorder usually characterized by narrow meningothelial proliferations abutting upon cortical plaques and exhibiting proliferations of small vessels with perivascular cuffs of fibroblast-like cells. The peculiarities were that the case lacked any leptomeningeal calcification - in line with the patient's age being the lowest so far reported for pathologically verified meningio-angiomatosis - and also exhibited intracortical clusters of mesenchymal cells that did not form vessels ("free fibroblasts"). Immunohistochemically perivascular cells were negative for S100, GFAP, desmin and factor-8-related antigen and were embedded in interstitial collagen of types III and VI as well as procollagen I, while "free fibroblasts" were surrounded by deposits of basement membrane collagen type IV. The results are consistent with a meningothelial origin of perivascular cells and "free fibroblasts".

Mitochondrial myopathies with necrotizing encephalopathy of the Leigh type.

Two patients with mitochondrial encephalomyopathy (MEP) serve to emphasize the variability of this group of diseases. Cerebral insults, mitochondrial cardiopathy, relapsing ileus, cerebral angioma, ataxia, and myoclonic seizures characterized the first case of an adult man with similar diseases in his family, interpreted as transitional form between mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and myoclonus epilepsy associated with ragged red fibers (MERRF). The second patient, a floppy infant with cardiomyopathy and myoclonism, statomotoric and mental retardation showed combined defects in mitochondrial respiratory chain at NADH-CoQ reductase and cytochrome c oxidase and a deficiency of carnitine. In both patients neuropathologically criteria of Leigh's syndrome could be demonstrated in the cerebral cortex, in case 2 also clinically. The classificatory problems of the relationships between KSS, MELAS, MERRF, Leigh's as well as Alpers' syndromes are discussed.