Utility of three-dimensional computed tomography for anatomical assistance in endoscopic endonasal transsphenoidal surgery.

Endoscopic endonasal transsphenoidal surgery (ETSS) has been widely applied to pituitary adenomas. However, anatomical orientation is difficult when structures of the sphenoidal sinus are complicated. This study investigated the usefulness of three-dimensional computed tomography (3D-CT) modeling in planning surgical procedures for ETSS and providing anatomical guidance during surgery.

Oct-3/4 modulates the drug-resistant phenotype of glioblastoma cells through expression of ATP binding cassette transporter G2.

Background: Drug resistance is a major obstacle for the efficacy of chemotherapeutic treatment of tumors. Oct-3/4, a self-renewal regulator in stem cells, is expressed in various kinds of solid tumors including glioblastoma. Although Oct-3/4 expression has been implicated in the malignancy and prognosis of glioblastomas, little is known of its involvement in drug resistances of glioblastoma.

miR340 suppresses the stem-like cell function of glioma-initiating cells by targeting tissue plasminogen activator.

Glioma-initiating cells (GIC) have stem-like cell properties thought to be sufficient for recurrence, progression, and drug resistance in glioblastomas. In the present study, we defined miRNA (miR)-340 as a differentially expressed miRNA in human GICs that inhibit GIC-mediated tumorigenesis. Furthermore, we defined tissue plasminogen activator (PLAT) as a critical direct target of miR340 for inhibition.

Oct-3/4 promotes tumor angiogenesis through VEGF production in glioblastoma.

Accumulating evidence shows that the expression level of Oct-3/4, a self-renewal regulator in stem cells, is positively correlated with the progression of various solid tumors. However, little is known regarding the influence of Oct-3/4 in the tumor angiogenesis of glioblastomas. In the present study, we subcutaneously transplanted Oct-3/4-overexpressing human glioblastoma U251 (U251/EGFP-Oct-3/4) cells into the right thighs of nude mice to evaluate the roles of Oct-3/4 in the tumor angiogenesis.

[A case of neurosurgery for meningioma in a chronic hemodialysis patient: perioperative management of chronic hemodialysis patients requiring neurosurgery].

Here, we report a case of primary intracranial tumor in a chronic hemodialysis patient in which neurosurgery was successful. A 50-year-old man who had been on hemodialysis for 4 years was admitted to our hospital with general fatigue. Neurological examination on admission revealed mild restless.

Prognosis of primary central nervous system lymphoma treated with radiotherapy alone.

Purpose: Standard treatment for patients with primary central nervous system (CNS) lymphoma involves combining high-dose methotrexate-based chemotherapy and radiation. However, chemotherapy is sometimes contraindicated, and radiotherapy alone becomes the only option. We retrospectively investigated the clinical outcomes of primary CNS lymphoma patients treated with radiotherapy alone.

[Intraventricular cryptococcoma successfully treated with liposomal amphotericin B and voriconazole: a case report].

Cryptococcal infections of the central nervous system (CNS) are infrequent in immunocompetent hosts and usually present as meningitis. However, fungal masses called cryptococcoma can sometimes be formed. We report a case in which intraventricular cryptococcoma in an immunocompetent patient was completely cured using liposomal amphotericin B (L-AMB) and voriconazole (VRCZ).

Oct-3/4 promotes migration and invasion of glioblastoma cells.

As a result of increased glioblastoma migration and invasion into normal brain parenchyma, treatment of local tumor recurrence following initial treatment in glioblastoma patients remains challenging. Recent studies have demonstrated increased Oct-3/4 expression, a self-renewal regulator in stem cells, in glioblastomas. However, little is known regarding the influence of Oct-3/4 in glioblastoma cell invasiveness.

Accuracy of diffusion tensor magnetic resonance imaging-based tractography for surgery of gliomas near the pyramidal tract: a significant correlation between subcortical electrical stimulation and postoperative tractography.

Background: Diffusion tensor (DT) imaging-based fiber tracking is a noninvasive magnetic resonance technique that can delineate the course of white matter fibers.

Objective: To evaluate the accuracy and usefulness of this DT imaging-based fiber tracking for surgery in patients with gliomas near the pyramidal tract (PT).

Methods: Subjects comprised 32 patients with gliomas near the PT.

Cancer stem-like cells of glioblastoma characteristically express MMP-13 and display highly invasive activity.

Glioblastoma is the most malignant type of primary brain tumor that has been shown to contain a small population of cancer stem cells. Recent studies have suggested that cancer stem cells cause tumor recurrence based on their resistance to radiotherapy and chemotherapy. Although the highly invasive nature of glioblastoma cells is also implicated in the failure of current therapies, it is not clear whether cancer stem cells are involved in invasiveness.

Evaluation of intraoperative brain shift using an ultrasound-linked navigation system for brain tumor surgery.

Image-guided neurosurgery using navigation systems is an essential tool to increase accuracy in brain tumor surgery. However, brain shift during surgery has remained problematic. The present study evaluated the utility of a new ultrasound (US)-linked navigation system for brain tumor surgery in 64 patients with intracranial tumors.

Downregulation of SPARC expression inhibits cell migration and invasion in malignant gliomas.

The secreted protein acidic and rich in cysteine (SPARC) is a secreted glycoprotein that plays an essential role in promoting the motility of invasive tumor cells. In the present study, we investigated the role of SPARC in the motile and invasive activities of human glioma cells by silencing the SPARC gene. Introduction of SPARC-targeted small interfering RNA (siRNA) into glioma cell lines resulted in downregulation of SPARC expression, and significantly suppressed glioma cell migration in vitro.

Silencing hypoxia-inducible factor-1alpha inhibits cell migration and invasion under hypoxic environment in malignant gliomas.

Malignant gliomas are characterized by active invasiveness, necrosis, and vascular proliferation. These pathological features have been speculated to be caused by tissue hypoxia. Hypoxia-inducible factor-1 (HIF-1), which is controlled by rapid stabilization of the HIF-1alpha subunit, is a pivotal transcriptional factor in the cellular response to hypoxia.

PTEN gene transfer suppresses the invasive potential of human malignant gliomas by regulating cell invasion-related molecules.

Loss of function of the tumor suppressor gene PTEN is more frequently encountered in high-grade malignant gliomas than in low-grade gliomas. High-grade gliomas are characterized by their extremely invasive behavior, suggesting that PTEN is one of the important regulators of cell motility and that alterations of its coding gene contribute to a much more invasive tumor cell phenotype. In order to clarify a role of PTEN in glioma invasion, we introduced the wild-type PTEN gene into human malignant glioma cell lines and investigated their motile and invasive activity in a brain slice model that presents circumstances analogous to normal brain conditions in vivo.

Downregulation of laminin alpha4 chain expression inhibits glioma invasion in vitro and in vivo.

The laminin family is a structural constituent of the extracellular matrix that plays an essential role in promoting the motility of infiltrative tumor cells. We investigated the role of laminin alpha4 chain, a subset of laminin-8, -9 and -14, in the motile and invasive activities of human glioma cells. All malignant glioma cell lines examined expressed more mRNA for the laminin alpha4 and beta1 chains than for the beta2 chain, indicating that these cells predominantly express the laminin-8 isoform.

Midkine promoter-based conditionally replicative adenovirus for malignant glioma therapy.

Little is known concerning promoters or gene therapy specific for malignant glioma. To explore the potential use of midkine promoter in gene therapy for malignant glioma, we constructed a midkine promoter-based conditionally replicating adenovirus (Ad-MK). Midkine was overexpressed in malignant glioma tissues but cyclooxygenase-2 was not.

Introduction of p16INK4a inhibits telomerase activity through transcriptional suppression of human telomerase reverse transcriptase expression in human gliomas.

The p16 and p53 tumor suppressor proteins, which are frequently altered in malignant gliomas, have been noted as regulators of telomerase activity. However, the link between telomerase regulation and these suppressor proteins has not been adequately clarified. In the present study, we demonstrated that p16, as well as p53, suppress telomerase activity through transcriptional regulation of human telomerase reverse transcriptase (hTERT) in malignant glioma.

Introduction of wild-type p53 enhances thrombospondin-1 expression in human glioma cells.

Malignant gliomas are distinguished from low-grade gliomas by their intense angiogenesis. In gliomas, p53 is the most frequently altered gene and is involved in the early phase of glioma development. In contrast, homozygous p16 gene deletion is more common in high-grade gliomas.

[Assessment of hemodynamics of meningioma with dynamic MR imaging].

Dynamic MR imaging provides hemodynamic information about normal and pathologic tissue of the brain. The purpose of our study was to evaluate the usefulness of dynamic MR imaging in the assessment of tumor vascularity and the tumor tissue blood flow of meningiomas. We studied 13 patients with meningiomas using dynamic spin-echo MR imaging.