Malignant transformation of supratentorial clear cell ependymoma.

Recurrence of clear cell ependymoma is not a rare condition, but malignant transformation of clear cell ependymoma has not yet been well presented. The authors report a 44-year-old man who presented with progressive right hemiparesis. A brain tumor in the left frontal premotor area was removed and an initial pathological diagnosis of oligodendroglioma was made. The tumor recurred 4 months later, and reoperation of the tumor and adjuvant local radiotherapy were performed. The patient subsequently underwent surgical removal of recurrent tumors on another four occasions (6 times in total) during a period of 11 years and finally died of the original disease. Histopathological studies of all surgical and autopsy specimens were carried out. The first and second surgical specimens did not contain any ependymal rosettes or pseudorosettes, and thus a diagnosis of oligodendroglioma was made. However, the third surgical specimen showed pseudorosettes. At this time, the tumor had an ultrastructural appearance compatible with ependymoma. Thereafter, the recurrent tumors showed anaplastic features such as nuclear pleomorphisms and necrosis with pseudopallisading. The autopsy specimens resembled a feature of glioblastoma but the tumor was sharply demarcated from the surrounding parenchyma.

Prognostic significance of the immunohistochemical expression of O6-methylguanine-DNA methyltransferase, P-glycoprotein, and multidrug resistance protein-1 in glioblastomas.

We studied the expression of O(6)-methylguanine-DNA methyltransferase (O(6)-MGMT), P-glycoprotein (Pgp), and multidrug resistance protein-1 (MRP-1) in 23 glioblastomas using RT-PCR, methylation-specific PCR, and immunohistochemistry, and analyzed their association with overall patient survival. Univariate analysis of collected data demonstrated that the expressions of O(6)-MGMT and MRP-1 detected by immunohistochemistry, in addition to the consistent factors, including preoperative Karnofsky performance scale (KPS), radical surgery, and tumor location and extension, were significant prognostic factors for the overall survival (OS) of patients with glioblastoma, who received nimustine (ACNU)-based chemotherapy in association with surgery and radiotherapy. Among them, following multivariate analysis, preoperative KPS, radical surgery, tumor location, and the expression of O(6)-MGMT remained as significant prognostic factors. These findings suggest that immunohistochemical analysis of O(6)-MGMT in patients with glioblastoma can be a useful method to predict the effects of chemotherapy and identify alternative chemotherapeutic regimens for O(6)-MGMT-positive patients.

[A case of bacterial aneurysm complicated by severe infectious endocarditis].

We report a case of bacterial aneurysm complicated by severe infectious endocarditis. A 34-year-old man developed idiopathic fever and general fatigue persisting for a month. He was admitted to our institution, and examinations revealed severe bacterial endocarditis with vegetation at the mitral valve and mitral incompetence. Right after admission, he suddenly developed acute cardiac infarction and cardiac arrest due to occlusion of the coronary artery by emboli from vegetation of the mitral valve. After achieving a good recovery, magnetic resonance (MR) imaging demonstrated an unruptured bacterial aneurysm at the distal branch of the left middle cerebral artery (MCA) supplying the left parietal lobe 5 days after admission, and T2* weighted images demonstrated multiple signal loss lesions, which were suspected of being thrombosed bacterial micro-aneurysms or micro-vasculitis. Although there was a risk of aneurysm rupture, we decided to proceed with mitral valve replacement by an artificial heart valve made of carbon, and repeatedly observed an unruptured bacterial aneurysm by serial MR imaging and angiography. Due to the preceding cardiac surgery, we were able to completely cure the severe infection and prevent new embolic showers. Under administration of antibiotics, the bacterial cerebral aneurysm did not increase over a period of 4 weeks, and finally the aneurysm disappeared about 6 weeks after admission. Although the timing of treatment of an unruptured bacterial aneurysm and cardiac surgery for infectious endocarditis associated with a bacterial cerebral aneurysm are controversial, we think that proceeding with cardiac surgery and observing the unruptured bacterial aneurysm by repeated MR imaging and angiography under administration of antibiotics was an appropriate strategy in this case.

Expression of vascular endothelial growth factor-A and mRNA stability factor HuR in human astrocytic tumors.

High-grade astrocytic tumors, such as glioblastoma, possess rich vascular components, which are necessary for their growth. VEGF-A is considered to be the major mediator of angiogenesis in malignant neoplasms including high-grade astrocytic tumors. The upregulation of VEGF-A expression in tumor cells is induced by two mechanisms: the transcriptional activation and the post-transcriptional stabilization of VEGF-A mRNA. While the former mechanism mediated by hypoxia inducible factor-1 alpha (HIF-1alpha) has been revealed, the latter mediated by mRNA stability factor HuR remains unclear in astrocytic tumors. In the present study, we investigated the expression of VEGF-A and mRNA stability factor HuR in supratentorial astrocytic tumors of 27 adults using RT-PCR, ELISA, and immunohistochemistry. Furthermore, we studied the involvement of HuR in the upregulation of VEGF-A expression using malignant astrocytoma cell lines. In higher-grade astrocytic tumors, the level of VEGF-A and microvascular density were elevated, cytoplasmic expression of HuR, which potentially means the protection of VEGF-A mRNA from degradation by ribonucleases, appeared, and they were correlated positively. In in vitro experiments, the inhibition of the cytoplasmic translocation of HuR protein by leptomycin B (LMB) reduced the upregulation of VEGF-A expression in malignant astrocytic tumor cells under hypoxic conditions. These findings suggest that the expression of VEGF-A and cytoplasmic translocation of HuR relates to the histological grade, and that HuR is involved in the upregulation of VEGF-A expression, in human astrocytic tumors.

Radiological findings for arterial dissection of the anterior cerebral artery.

We treated a patient with anterior cerebral artery (ACA) dissection that caused an ischaemic stroke, and investigated serial changes over time by using three different radiological methods. The conventional angiography findings for ACA dissection corresponded to those of computed tomography (CT) angiography, but not those of magnetic resonance angiography for each phase. We presume that the results were based on the velocity of the blood flow in the pseudolumen of the dissected artery, and we believe that CT angiography is a useful and less invasive diagnostic tool for intracranial arterial dissection.

Acquisition of resistance to antitumor alkylating agent ACNU: a possible target of positron emission tomography monitoring.

Early detection of tumor response to chemotherapy is of great importance for appropriate treatment of tumors. In this study, characteristics of two positron emission tomography (PET) tracers, [(18)F]2-fluoro-2-deoxy-D-glucose (FDG) and[(18)F]3'-fluoro-3'-deoxy-thymidine (FLT), in the early detection of tumor cell response as well as tolerance development to chemotherapy was compared using rat C6 glioma cells and 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosoureahydrochloride (ACNU). ACNU is an alkylating agent known to induce drug resistance through expression of O(6)-methylguanine-deoxyribonucleic acid methyl transferase (O(6)-MGMT). We established an ACNU-resistant C6 glioma cell line (C6/ACNU) and investigated the effect of ACNU on the uptake of FLT and FDG. In C6 cells, DNA synthesis presented as [(3)H]thymidine ([(3)H]Thd) incorporation into DNA was quickly suppressed by ACNU. In C6/ACNU cells, the suppression was recovered promptly, indicating that DNA alkylation occurs initially but highly expressed O(6)-MGMT repairs DNA, leading to the recovery of DNA synthesis. The patterns of FLT uptake in C6 and C6/ACNU were difficult to distinguish in the very early stage of the treatment, though it was reported that FLT uptake well correlated with proliferation in certain conditions. FDG uptake showed different patterns between the resistant and control cells, with significantly decreased uptake in C6 cells and unchanged uptake in C6/ACNU cells at 18-24 h after the treatment. Though difficult to be directly translated into clinical situation, the present study will provide a base to develop an appropriate protocol to assess tumor response to treatment by PET and to design effective treatment plans.

Meningeal plasma cell granuloma with relapsing polychondritis. Case report.

Relapsing polychondritis (RP) is a rare systemic disease characterized by recurrent inflammation of the cartilaginous structures and connective tissue. Central nervous system lesions in association with RP have occasionally been reported, but intracranial mass lesions have not been described. The authors report the first such case, in which a 51-year-old man presented with parasagittal meningeal plasma cell granuloma with RP. The mass was subtotally resected and adjuvant radiotherapy was administered. The patient did not experience any recurrence of the lesion during an 8-year follow-up period. In this case, the exact diagnosis of RP was made based on symptoms of respiratory tract chondritis, which was successfully treated by the placement of tracheobronchial stents.

Cervical extradural meningioma with rapidly progressive myelopathy.

A 50-year-old man noticed numbness of both hands. Muscle strength in the upper and lower extremities progressively deteriorated, and he became unable to stand or hold a cup over a five-day period. MRI showed an extradural tumour encasing the anterior, posterior and right lateral aspects of the cervical spinal cord, maximal at C3-4 but extending to C1, and emerging from the right C3-4 intervertebral foramen. At surgery, the tumour was entirely extradural. Histological examination revealed a meningioma. The patient recovered without neurological deficit with no recurrence 3 years after surgery.

Atlas hypoplasia associated with non-traumatic retro-odontoid mass.

A 38-year-old man presented with progressive cervical myelopathy due to atlas hypoplasia associated with non-traumatic retro-odontoid mass. The neuroimaging findings suggested hypertrophy of the transverse ligament of the atlas. No histological confirmation of the retro-odontoid mass was obtained. Clinical manifestations improved after posterior decompression. Decompressive laminectomy of the atlas with or without fusion can achieve a good outcome in such cases.

Spinal tanycytic ependymoma with hematomyelia--case report--.

A 58-year-old man presented with an extremely rare case of "pure type" spinal tanycytic ependymoma associated with hematomyelia manifesting as sensory disturbance of the bilateral hands and weakness of the right arm. Magnetic resonance imaging demonstrated a tumor in the spinal cord from C-2 to C-4 levels. The soft gelatinous tumor was subtotally resected and the adjacent chronic liquid hematoma was aspirated. The immunohistochemical and ultrastructural findings indicated a diagnosis of tanycytic ependymoma.

Immunohistochemical and ultrastructural study of gap junction proteins connexin26 and 43 in human arachnoid villi and meningeal tumors.

Human arachnoid villi and meningiomas are known to have gap junctions formed by connexin (Cx) proteins. We examined the expression and localization of Cxs in normal human arachnoid villi and meningeal tumors (meningiomas and hemangiopericytomas) by immunohistochemistry and Western blots. In arachnoid villi, strong immunopositivity for connexin26 (Cx26) and connexin43 (Cx43) was detected in the cap cell layer, cap cell cluster, and central core. They were weakly expressed in the fibrous capsule. In meningiomas they were strongly expressed in the meningotheliomatous area and weakly positive in the fibrous area. None of them were expressed in hemangiopericytomas. By immunoelectron microscopy, Cx26 and Cx43 were distributed on the cell membranes in arachnoid villi and meningiomas. In the Western blots in arachnoid villi and meningiomas, Cx26 and Cx43 were shown at bands with molecular weights of 26 kD and 42-47 kD, respectively. The degree of positivity for Cxs was different between subtypes of meningiomas. These findings suggest that expression of Cx26 and Cx43 might be related to the differentiation of the arachnoid villi and meningiomas, and exhibit the different origin of various subtypes of meningiomas. We proposed that Cx expression is one of the useful markers for the differentiation of meningioma and hemangiopericytoma.

Evaluation of prognostic factors and clinical outcome in elderly patients in whom expansive laminoplasty is performed for cervical myelopathy due to multisegmental spondylotic canal stenosis. A retrospective comparison with younger patients.

OBJECT: It remains unclear whether elderly patients with compressive cervical myelopathy can be expected to experience a promising surgery-related outcome after undergoing expansive laminoplasty. The purposes of this study were to evaluate the efficacy of expansive laminoplasty in elderly patients with cervical myelopathy due to multisegmental spondylotic canal stenosis and to analyze the effect of preoperative prognostic factors on outcome in elderly compared with younger patients. METHODS: The authors reviewed the cases of 22 elderly (> 70 years of age) and 39 younger patients in whom expansive open-door laminoplasty was performed for cervical myelopathy due to multisegmental spondylotic canal stenosis. The pre- and 12-month postoperative clinical symptoms were evaluated using the Japanese Orthopaedic Association (JOA) disability scale. Factors affecting the clinical outcome were statistically analyzed by evaluating the recovery rate calculated from the JOA scale. There were no significant differences in the mean value of the preoperative factors, especially preoperative duration of symptoms and severity of preoperative disease, between the elderly and younger patient groups. In all patients, age at the time of the operation was shown to exert no significant influence on clinical outcome. The mean recovery rate was 58.8% in the elderly group and 61.8% in the younger group, and there was no significant intergroup difference. Improvement or attenuation in impaired upper- and lower-leg motor function was shown in all patients as was an absence in decline of sensory impairment of the extremities. In the elderly group, both the duration of symptoms and the severity of canal stenosis significantly (p < 0.05) affected the clinical outcome. In the younger group, the severity of preoperative symptoms had a significant (p < 0.05) influence on clinical outcome, whereas duration of the symptoms did not appreciably affect clinical improvement. CONCLUSIONS: Open-door expansive laminoplasty showed a promising effect on clinical outcome in elderly and younger patients with multisegmental cervical canal stenosis. Significant predictive factors for clinical outcome in the elderly patients were the duration of symptoms and the severity of stenosis, which may involve the static factor causing the cervical myelopathy. To improve the elderly patients' disability, surgery must be performed as early as possible before irreversible changes in the spinal cord develop.

Ultrastructure of capillary endothelium in pilocytic astrocytomas.

The aim of this study was to assess the capillary ultrastructure of pilocytic astrocytomas with gadolinium contrast enhancement on magnetic resonance imaging (MRI). Cysts were identified in all cases with pilocytic astrocytoma. Histological investigation focusing on the vascular structure was performed by light microscopy and electron microscopy in four pilocytic astrocytomas. In the pilocytic astrocytomas, light microscopic examination demonstrated vascular abnormalities (fibrosis, hyalinization, and vascular proliferation), and electron microscopic examination revealed fenestration and vesicles in the capillary endothelium. Fenestration of the vessels and vascular abnormalities with degeneration are suggested to develop both contrast enhancement on neuroimaging and cystic formation in pilocytic astrocytomas.

[Angiographic features of anoxic encephalopathy in the acute phase: a case report].

We present an angiographic feature of anoxic encephalopathy in the acute phase. A 68-year-old woman suddenly presented with deep coma. Examinations of her blood and electrocardiography did not reveal the origin of consciousness disturbance, and computed tomographic (CT) scans demonstrated no significant findings. We immediately performed cerebral angiography because we suspected brain stem infarction. A 3-vessel study (bilateral carotid and left vertebral angiography) revealed remarkable delays in cerebral circulation time or arteriovenous circulation time, although it did not show occlusion of cerebral vessels. The follow-up brain magnetic resonance (MR) images revealed anoxic encephalopathy, which might be derived from transient cardiac arrest. The patient has been in a vegetative state for one year. Although many reports have described CT scans and MR images of anoxic encephalopathy in the acute or subacute phases, there have been no reports about the angiographic features. We found remarkable delays in cerebral circulation time in the acute phase of anoxic encephalopathy, which was considered to be caused by cytotoxic edema from severe hypoxia or ischemia.

Coincident choroid plexus carcinoma and adrenocortical tumor in an infant.

We report a case of a 20-month-old girl with a large choroid plexus carcinoma arising in the left lateral ventricle and an adrenocortical tumor. Following brain tumor resection, the patient was treated with radiation and chemotherapy. The adrenocortical tumor was found with the manifestation of precocious puberty. TP53 gene mutation (exons 4-10) was not detected in either specimen. The patient had leptomeningeal dissemination and died 26 months later.

Zinc-L-carnosine binds to molecular chaperone HSP70 and inhibits the chaperone activity of the protein.

In this study, we have investigated the specific binding proteins of Zinc-L-carnosine (Polaprezinc) using Polaprezinc-affinity column chromatography in vitro. A protein having a 70-kDa molecular mass was eluted by the linear gradient of 0-1.0 mM Polaprezinc from the affinity column and the protein was identified as the molecular chaperone HSP70 by immunoblotting. The chaperone activity of HSP70 was completely suppressed by Polaprezinc. The ATPase activity of HSP70 was affected to some extent by the reagent. In the circular dichroism (CD) spectrum, the secondary structure of HSP70 was changed in the presence of Polaprezinc, i.e. it decreased in the α-helix. We have determined the Polaprezinc-binding domain of HSP70 by using recombinant HSP70N- and C-domains. Although Polaprezinc could bind to both the N-terminal and the C-terminal of HSP70, the HSP70N-domain has a high affinity to the drug. Regarding the peptide cleavage of the HSP70N- and C-domains with proteinase K, the intact HSP70N still remained in the presence of Polaprezinc. On the other hand, the quantity of the intact C-domain slightly decreased under the same conditions along with the newly digested small peptides appeared. It has been suggested that Polaprezinc binds to HSP70 especially in the N-domains, suppresses the chaperone activity and delays an ATPase activities of HSP70.

Glioblastoma with oligodendroglial components: glioblastoma or anaplastic oligodendroglial tumors.

There have been some recent reports about glioblastoma with oligodendroglial (OG) components and malignant glioma with primitive neuroectodermal tumor (PNET)-like components. We investigated whether the presence and extent of OG components and PNET-like components influenced the prognosis in patients with glioblastoma. Eighty-six patients with glioblastoma were divided into an OG group (28 %), which revealed areas with a honeycomb appearance, and a non-OG group (72 %) without a honeycomb appearance. Patients with glioblastoma were also divided into a PNET group (27 %), which revealed areas with PNET-like features defined as neoplastic cells with high N/C ratios and hyperchromatic oval-carrot-shaped nuclei, and lacked the typical honeycomb appearance, and a non-PNET group (73 %) without PNET features. There were no significant differences in overall survival among the OG, the non-OG, the PNET, and the non-PNET groups. Two patients who survived longer than 36 months had both OG and PNET components with 1p or 19q loss of heterozygosity. Perinuclear halo, which is a characteristic feature of oligodendrogliomas, is an artifact of tissue fixation. Therefore, we should not readily use the term glioblastoma with OG components. PNET-like components, which are considered rare in malignant gliomas, may be frequently identified in glioblastomas.

Clinicopathological features in the recurrence of oligodendroglioma and diffuse astrocytoma.

To investigate whether grade II oligodendroglioma was transformed to glioblastoma or not, histopathological evaluation of recurrent oligodendrogliomal tumors (OG) and diffuse astrocytomas (DA) was performed. The OG group was composed of ten patients with OG, including seven oligodendrogliomas and three oligoastrocytomas. The DA group was composed of ten patients with DA, including eight fibrillary astrocytomas and two gemistocytic astrocytomas. The histopathological parameters of glioblastoma including nuclear atypia, multinucleated giant cells, glomeruloid tufts (GT) as a marker of microvascular proliferation, necrosis, and the Ki-67 staining index were investigated. Evaluation of these parameters was scored as follows: 0, none; 1, sporadic; 2, partial; 3, extensive. There were no cases of transformation to glioblastoma in the OG group. There were five cases of transformation to secondary glioblastoma in the DA group. In recurrent tumors, scores of GT and necrosis in the OG group were significantly lower than those in the DA group (p < 0.005). Nuclear atypia and high proliferative activity (Ki-67 index) were identified in recurrent tumors of the OG group. Our study suggested that the extent of GT and necrosis in recurrent OG was less than that in recurrent DA, and transformation to glioblastoma from oligodendroglial tumor was exceptional.

A phase I/II clinical trial investigating the adverse and therapeutic effects of a postoperative autologous dendritic cell tumor vaccine in patients with malignant glioma.

Previous clinical trials of dendritic cell (DC)-based immunotherapy in patients with glioblastoma multiforme (GBM) have reported induction of systemic immune responses and prolonged survival. From 2003 to 2005, we performed a clinical trial in which patients with malignant glioma underwent surgery for maximal cytoreduction followed by a 6-month 10-injection course of autologous DC-tumor vaccine therapy, each injection containing 1-6×10(7) DC. Of the 17 treated patients (16 with World Health Organization grade IV and one with grade III glioma), eight (47.1%) had an initial transient elevation in aspartate aminotransferase (AST)/alanine aminotransferase (ALT). Vaccination caused some tumor shrinkage and increased concentration of tumor-infiltrating CD8(+) lymphocytes. Median survival and 5-year survival were 525 days and 18.8%, respectively, for 16 patients with grade IV glioma (381 days and 12.5% for eight newly diagnosed; 966 days and 25% for eight relapsed patients) compared to 380 days and 0% for 63 historical control patients. We concluded that autologous DC-tumor immunotherapy benefits patients with malignant glioma but may cause transient but reversible elevation of serum AST/ALT levels.

Proliferation of vascular smooth muscle cells in glioblastoma multiforme.

OBJECT: Glioblastomas multiforme (GBM) contain a higher number of alpha-smooth muscle actin (SMA)-positive vascular smooth muscle cells (VSMCs) than those in the respective normal neuronal tissue. The role of VSMCs during angiogenesis is unclear, and it is also uncertain whether and to what extent angiogenic factors might be involved in GBM VSMCs. In GBMs, the contribution of VSMCs in angiogenesis accompanying endothelial proliferation and the correlation of VSMC proliferation with vascular endothelial growth factor (VEGF) expression were examined using an immunohistochemical method. METHODS: The examined material, including surrounding brain tissue, came from 12 cases (6 men and 6 women) with classic GBM. Microvessel densities (MVDs) of CD31-immunoreactive vessels (CD31-MVD) and SMA-immunoreactive vessels (SMA-MVD) were obtained in areas selected from white matter, boundary, tumor (concentrated area of tumor cells), and perinecrosis. Subsequently, the SMA-MVD/CD31-MVD (SMA/CD31) rate, representing the percentage of vessels with VSMCs in the region, was calculated in each area. The VEGF immunoreactivity of tumor cells was examined, and cases were divided into 2 groups: < 30% VEGF expression of tumor cells (low VEGF group) and > 30% VEGF expression of tumor cells (high VEGF group). RESULTS: The SMA/CD31 rate of the boundary was significantly lower than that of the tumor (p < 0.005) and perinecrosis (p < 0.001). The SMA/CD31 rate of the high VEGF group was significantly higher than that of the low VEGF group (p < 0.05) in the tumor. CONCLUSIONS: In GBMs, the transformation and proliferation of VSMCs may accompany neovascularization and may also be induced by angiogenic factors.