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.

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.

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.

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.

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.

Nestin expression in astrocytic tumors delineates tumor infiltration.

Nestin is an intermediate filament protein expressed in undifferentiated cells during central nervous system development, and glioma is known to be a highly infiltrative tumor. We determined whether nestin was expressed in astrocytic tumors and could identify infiltrating tumor cells. We screened 65 archival, paraffin-embedded adult astrocytic tumors using immunohistochemical staining and computerized overlaid photographs. Normal biopsied brains and metastatic brain tumors were also examined. The intensity of nestin expression corresponded to the tumor grade. All 33 glioblastoma cases showed positive and extensive staining, which was less positive in diffuse astrocytoma. Overlaid images showed that nestin immunostaining delineated tumor invasion into adjacent gray and white matter. Nestin is a useful marker for examining the infiltration of malignant cells into surrounding tissue.

Clinical implication and prognosis of normal baseline cerebral blood flow with impaired vascular reserve in patients with major cerebral artery occlusive disease.

OBJECTIVE: To investigate the prognosis of patients with cerebrovascular steno-occlusive disease who have preserved baseline cerebral blood flow (CBF) and reduced cerebral vasoreactivity (CVR), they were followed up after scans of positron emission tomography (PET). METHODS: Fifty-seven patients with symptomatic unilateral major cerebral arterial occlusion or severe stenosis underwent O-15 gas and water PET scans to measure cerebral blood volume, metabolic rate of oxygen, oxygen extraction fraction (OEF), and CBF at the baseline and after acetazolamide administration. Thirty of them (mean age 60 +/- 10 years) had normal ipsilateral CBF, and were followed prospectively at least 30 months from the last ischemic event. They were medically treated for cerebral circulation and underlying diseases during follow-up periods. The primary endpoint was determined as stroke recurrence during the follow-up. RESULTS: Thirty patients were divided into two groups of reduced CVR (N = 16, 63 +/- 8 years) and normal CVR (N = 14, 56 +/- 10 years) on the basis of CVR values from healthy volunteers. None of them showed significant laterality in baseline CBF and OEF between the hemispheres although patients with reduced CVR showed a tendency of ipsilateral increases in OEF and CBV. Patients were followed up for 50.5 +/- 19.0 and 48.1 +/- 12.4 months in the reduced and normal CVR groups, respectively. Although one patient with reduced CVR died of heart disease, there was no incidence of ischemic events during follow-up periods for either group. CONCLUSION: In the present prospective study, patients with sufficient baseline CBF showed good prognosis and no difference in recurrent stroke risks even though they had poor CVR in the affected hemisphere, indicating that these patients can be treated by medication for cerebral circulation and baseline diseases if they have high risk factors for neurosurgical treatment.

Epstein-Barr virus-associated primary central nervous system lymphoma in the Japanese population.

The incidence of Epstein-Barr virus (EBV)-associated primary central nervous system (CNS) lymphoma in Japan was assessed using in situ hybridization of EBV-encoded small ribonucleic acid-1 (EBER-1) to identify the presence of EBV in 22 cases of formalin-fixed and paraffin-embedded primary CNS lymphoma. All cases were B-cell lymphoma. EBER-1 expression was observed in the nuclei of 3 of 22 primary CNS lymphoma cases (13.6%). The incidence of EBV-positive lymphoma in Japanese cases is higher than previously reported from Western countries. Patients with EBV-positive primary CNS lymphoma showed shorter survival than those with negative tumors (median 4 months vs. 26 months). EBER-1 in situ hybridization for the detection of EBV infection is rapid and reliable. Infrequent association suggests a different pathogenetic mechanism in the evolution of these tumors. Geographical differences in the incidence of EBV-associated primary CNS lymphoma may reflect epidemiological factors.

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.

Thymic mucosa-associated lymphoid tissue lymphoma associated with bilateral orbital pseudotumor.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the thymus is a rare condition, often characterized by its occurrence in a context of autoimmunity. We reported a first case of thymic MALT lymphoma following bilateral orbital pseudotumor. A 48-year-old man presented with bilateral exophthalmos diagnosed as orbital pseudotumor. His symptoms were relieved by an oral corticosteroid. Eleven years later, a mediastinal tumor was incidentally discovered. A thymectomy was performed, and histological examination revealed that the mass was a MALT lymphoma. There was no recurrence with no further treatment.

[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.

[Hypoxic ischemic encephalopathy with atypical findings on CT and MR imaging: two case reports].

We report 2 cases of hypoxic ischemic encephalopathy with atypical findings on computed tomographic (CT) and magnetic resonance (MR) imaging for the acute to subacute stage. Case 1: A 78-year-old man with larynx cancer suffered cardiac arrest after suffocation. Cardiopulmonary resuscitation, was performed; the patient then went into a deep coma and also developed severemyoclonus. CT scans on day 0 and day 3 after the arrest revealed no abnormalities MR imaging was performed on day 13 to evaluate cerebral anoxia; however, no abnormal findings were obtained. Since no abnormalities were detected both on CT and MR imaging, we expected that the prognosis would be good; however, the patients did not recover from coma and remains in a persistent vegetative state. Case 2: A 54-year-old man developed cardiac arrest after anaphylactic shock caused by insect bite. After cardiopulmonary resuscitation, the patient lapsed into a deep coma. CT scans performed on day 1 and 3 after the cardiac arrest revealed slight subarachnoid hemorrhage at the surface of the right cerebral cortex along the falx cerebri. MR images obtained on day 10 demonstrated slight hemorrhage at the surface of right cerebral cortex, but no abnormalities in basal ganglia, thalamus, cortex, and white matter. The transient damage of the blood brain barrier caused by hypoxia and ischemia was thought to induce the slight subarachnoid hemorrhage after cardiopulmonary resuscitation. The patient demonstrated early recovery and was almost completely recovered with slight agnosia. MR imaging to rule out hypoxic-ischemic encephalopathy may not have been timed appropriately in both the case, our radiological findings are usual as compare to the findings presented in other similar reports. The variations in the findings of CT and MR imaging in the case of hypoxic-ischemic encephalopathy should be clarified, and the prognosis and management of this condition should be planned on the basis of not only the neuroradiological images but also the neurological signs and symptoms.

Pathology of pineal parenchymal tumors.

Pinea l parenchymal tumors (PPTs) are neuroepithelial tumors that arise from pineocytes or their precursors. According to the currently revised WHO classification of tumors of the central nervous system, PPTs are subdivided into well-differentiated pineocytoma, poorly differentiated pineoblastoma, and PPT with intermediate differentiation (PPTID). Pineocytomas are slow-growing neoplasms composed of small mature cells resembling pineocytes. Large pineocytomatous rosettes are the most characteristic appearance. Pineoblastomas are the most primitive form and have a highly malignant biological behavior. PPTIDs show an intermediate histological grade of malignancy between pineocytomas and pineoblastomas. Immunohistochemically, PPTs are positive for several neuronal markers, including synaptophysin, neurofilaments, class III beta-tubulin, and chromogranin A. Photosensory differentiation is associated with immunoreactivity for retinal S-antigen and rhodopsin. Ultrastructurally, dense core vesicles and clear vesicles are present in both cytoplasm and cellular processes, the latter showing occasional synapse-like junctions. In some cases, ultrastructural evidence of photoreceptor differentiation, such as synaptic ribbons, microtubular sheaves, and cilia, is observed. Little is known about the genetics responsible for the development of PPTs. Several chromosomal abnormalities have been identified frequently in pineoblastomas and PPTIDs but less commonly in pineocytomas. Pineoblastomas are known to occur in patients with RB1 gene abnormalities, and these tumors also develop in patients with familial bilateral retinoblastomas (trilateral retinoblastoma syndrome). However, specific gene abnormalities involved in the tumorigenesis of PPTs have not been identified.

Pathology of intracranial germ cell tumors.

Intra cranial germ cell tumors (GCTs) usually arise in midline structures, including the pineal or suprasellar regions of children and young adults. The classification of GCTs includes germinoma, teratoma, yolk sac tumor, embryonal carcinoma, and choriocarcinoma. However, intracranial GCTs are often of mixed histologic composition (mixed GCTs), and only germinoma and teratoma are likely to be encountered as pure tumor types. Although GCTs are usually identified using conventional histological techniques, immunohistochemical studies are very useful for delineating these entities, using special markers such as human chorionic gonadotropin, alpha-fetoprotein, human placental alkaline phosphatase, cytokeratin, as well as c-kit and OCT4. Ultrastructural examination is also useful in confirming the identity of these tumors. Genetic alterations specifically encountered in central nervous system GCTs are largely unknown. Patients with Klinefelter syndrome or Down syndrome appear to be predisposed to the development of gonadal as well as intracranial germinomas. Frequent imbalances of chromosomes have been described in intracranial GCTs, including chromosomes 1, 8, 12, 13, 18 and X. Recently, p14 and c-kit gene alterations have been reported, particularly in some intracranial germinomas; however, their importance remains unclear.

Melanocytoma in the orbital apex.

We report a case of a 49-year-old man presenting with a melanocytoma located in the orbital apex. The tumor was subtotally removed and adjuvant chemotherapy was given. The patient has remained under follow-up for the past 12 years without any evidence of recurrence. Although the characteristic neuroradiological images of the lesion prove the presence of melanin, histological examination is crucial to establish the diagnosis of melanocytoma. Besides the clinical and neuroradiological presentation, the histological, immunohistochemical, and ultrastructural findings are described. To our knowledge, this is the second published case of intraorbital melanocytoma initially confined to the orbital apex. Melanocytoma should be included in the differential diagnosis of intraorbital tumors in such a location.

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.

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.

Chromosome 1p and 19q deletions in malignant glioneuronal tumors with oligodendroglioma-like component.

Malignant glioneuronal tumors (MGNT) are suggested to be a new entity of glioma defined morphologically as any malignant glioma showing immunohistoichemical evidence of neuronal differentiation. We encountered seven cases of MGNT with oligodendroglioma-like component and investigated alternations of chromosome 1p and 19q in these tumors. Seven patients ranged from 33 to 62 years of age, four females and three males. Immunohistochemical study of these tumors was performed using neuronal markers (synaptophysin, neurofilament, beta-tubulin, chromogranin A and NeuN), astrocytic marker (GFAP) and Ki-67. We undertook a molecular cytogenetic study of tumor specimens obtained from seven patients using fluorescence in situ hybridization (FISH) with DNA probes mapping to chromosome 1p36, 1q25, 19p13 and 19q13. Histologically, these tumors resembled anaplastic oligodendroglioma. Immunohistochemically, tumor cells were immunoreactive for synaptophysin (7/7), neurofilament (6/7), beta-tubulin (5/7), chromogranin A (4/7), NeuN (2/7) and GFAP (7/7). The Ki-67 labeling index ranged from 4.5% to 20.7%. FISH analysis demonstrated either 1p or 19q deletion in all seven cases (100%) and both 1p and 19q deletions in five cases (71%). The 1p deletion was detected in six of seven cases (86%) and 19q deletion was also detected in six (86%). 1p and 19q deletions were present in MGNT, especially those with oligodendroglial components. We suggest that the oligodendroglial-like feature was associated with not only 1p or 19q loss but also differentiation along neuronal cell lines as a factor of favorable prognosis in glial tumors. It is inappropriate to make a diagnosis of oligodendroglioma based only on morphological resemblance to oligodendroglia.